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Archive for the ‘Tools’ Category

Who Says I Have no Filter?

Tuesday, January 17th, 2017

Mysteries of the Y Capacitor, Revealed

I’m becoming more of a big electronics genius every day. Staying humble is not easy.

Yesterday I posted about the resurrection of my old HP 3300A function generator, and I mentioned the weird capacitors across the AC mains. Right where the three wires entered the box, there were two caps (in one package). One went from neutral to ground, and the other went from hot to ground.

One of these caps had shorted out, and that had killed the generator. I had to replace them. When a cap between hot and ground shorts out, you have a hot wire going straight to ground, and that is pretty worthless.

A commenter mentioned a different type of component which would look just like a dual capacitor. He said EMI (electromagnetic interference) filters resembled capacitors, and he said they had inductors inside them. I went back to my schematic to check, and I didn’t see any inductors, so I think all I had were caps.

I started reading up on this stuff. I could not figure out why anyone would need filters right before a big transformer and two big reservoir caps with diodes. The reservoir caps and diodes kill AC and turn it into DC, so I would think they would also kill any high frequencies in the line. My guesses are worth about what I charge for them, however.

After some Googling, I learned that what I have is a “type Y” setup. Caps like this are intended to keep interference from passing through the power connection. If it’s coming from outside, they keep it out. If it’s coming from inside your device, they keep it inside.

I can’t call the dead HP engineers who designed the machine, so I can’t ask what the big concern was. I was thinking maybe the AC wires, if not filtered at the entrance to the box, could act as antennas and shoot RF into other internal components, distorting the signal the machine provides. I don’t really know.

Here’s an important fact: it is well known that when capacitors in this configuration die, they can short, and then you can get shocked. This is bad, unless you view death as a postive outcome. You need special capacitors designated X or Y. These capacitors will resist things like power surges. Do they eventually die from old age and short anyway? Search me.

I know nothing about X capacitors, but the Y type come in two varieties: Y1 and Y2. Y1 capacitors are expensive industrial components, so people use Y2. You can find them on Ebay. I guess I’ll have to order some and replace the brand-new capacitors I just installed.

I am wondering if there is any point in putting caps like this on my guitar amps. I think the odds that the sound will improve are infinitesimal, and the chance of electric shock is appreciable, but it would still be a cool feature to brag about.

I have always assumed it was impossible to get a shock from a grounded metal box, but I am used to being proven wrong, so I may as well get the caps.

There are components made to divert power surges. I forget what they’re called. There is a list of “immortal mods” for guitar amplifiers, and it lists things you can do to an amp to make it resistant to failure. The power surge shunt things are on the list. You can look it up. I don’t know if they would work on Y caps. Haven’t checked.

I know this information is fascinating to everyone. Try not to get so engrossed you forget to look away from my blog and do whatever it is you’re being paid to do.

Waves of Joy

Monday, January 16th, 2017

Victory is Mine

People are probably dying to find out whether I succeeded in getting my old HP 3300A function generator working, so here I am to help. It is now running.

What is a function generator? It’s sort of the opposite of an oscilloscope. A scope displays electrical waveforms. A function generator creates them. I don’t know all the reasons why this is useful, but I can list one. If you have something like an amplifier, and you want to see whether a signal is finding its way through it, you can hook a function generator up to the input. This keeps a varying voltage going into the amp while you check the circuit at various points. For me, as a guitar amp builder, the alternative is to hook up a guitar and pick a string over and over. That’s work, and as I have often said, work is against policy.

I suppose you could also check an amp’s frequency response by sending different frequencies through it.

For some reason I no longer recall (probably the guitar amp thing), I bought a used Hewlett-Packard function generator a few years back. I don’t know when it was made, but I know they were selling them in 1965. It’s the size of a big briefcase, and it weighs maybe 25 pounds. It will produce several types of waves (sinusoidal, square, etc.) at frequencies up to 100 kHz. I’ll bet it was really expensive when it was new, because it contains approximately 4 million components which were installed by hand.

A few weeks back, I pulled it off the shelf to see if it worked, and I was disturbed to find that I had no cord for it. Did I ever have a cord for it? Search me. I could not find it.

The cords we have on computers now are called C14/C15 cords. C15 is the female end. I leave it to you go guess what the male end is. As you know, these cords have three conductors, and the connectors at the ends are in a line, with the ground conductor above the others (or below them, if you hold it that way). The function generator had a male receptacle for a cord, but it was a bizarre old setup known as the PH-163. I have written about it before, presumably to everyone’s delight. It’s sort of like a C14/C15, but it has oval pins.

You would think there would be ten billion PH-163 cords for sale on Ebay, but there aren’t. The best deal I found was about $25, for a cord for a machine which, for all I knew, would never work. My solution? I took one of the thousands of spare cords I’ve accumulated, and I bought a receptacle for it. I opened up the receptacle hole in the generator cabinet and installed the new receptacle, and that allowed me to use a new cord.

I was really proud of that job, because I had to use a whole lot of tools, and the stuff I was working on was very small. I had to use a Dremel, two files, a drill, a soldering iron, a solder sucker, a power screwdriver and some other stuff I forget.

Because I know you’re excited about this, I will post a photo, looking down at the receptacle.

The two red things are new capacitors I put in. I will tell you about that shortly.

I got it wired up, and I plugged it in. POOF. It failed to work, and the lights in the garage flickered. Seemed like there was a short.

I looked it over and asked questions on forums, and I learned something interesting. Sometimes old capacitors short out for no apparent reason. One day, you have a capacitor which blocks DC and many AC frequencies, and the next day, you have what might as well be a straight copper wire with zero resistance. The transformer on the generator had a dual capacitor across the main power wires, presumably to filter out crap, and when I checked the cap, I got 4 ohms of resistance (a short) on one side.

A dual capacitor (that name may be wrong) is a capacitor that looks like a single capacitor yet which contains two capacitors that share one lead. It will have one lead in the middle that goes to both caps, and it will have two leads on the sides, each of which goes to one cap. I do not know why HP chose to use a dual capacitor, but it seems like a bad idea, because when one side crapped out, I had to replace both sides.

I guess that’s not really true, but I felt like it was stupid to keep an old capacitor when its twin had just kicked the bucket.

Meanwhile, the generator’s fuse had melted. After I tried running it in the garage, I took it in my office and plugged it in, and the breaker that powers the outlet popped. I assume this is what killed the fuse. I should have used a current limiter, but I didn’t.

Here’s something that may be useful to doofuses like me who can’t read fuses. The fuse in the generator said “6/10A” on it. I couldn’t figure that out. Six amps? Ten amps? Six amps on even-numbered days and ten on odd-numbered days? It turns out it means 0.6 amps, which is something the manufacturer could have stamped on it instead of “6/10A”. I had to go on Ebay and order new 6/10A fuses.

I also had to order the caps. I have maybe 2000 caps on hand at a given time, and when the generator needed one, I didn’t have a single 0.01uF.

When everything arrived, I put the correct fuse in the machine and solder the caps in place. You can see them in the photo. I even saved the funky old insulation from the old cap and put it on the new cap leads.

The solder sucker I used is wonderful. If you to to an electronics store at random and ask for a solder remover, they will give you a clumsy foot-long plastic thing which is hard to use accurately. I found a little metal Japanese solder sucker about four inches long, and it’s much more precise. Solder tends to get stuck in the nozzle, so you you have to stop and get it out, but it’s worth it because it’s so easy to use.

I got everything put together and plugged the machine in. No joy. After going through all this, I found that the on switch was dead. No problem, right? Buy another one for three dollars on Ebay. Sadly, that option was not open to me. This thing had an expensive “Marco Oak Press-Lite” switch, which is apparently an aircraft-grade switch. It lights up when it’s on. New ones are selling for sums well into two figures. No way was I paying that.

I figured out which pins on the switch needed to be shorted to turn the machine on, and I soldered a wire between them. Now the machine turns on when you plug it in. I ordered a small toggle switch, and when it arrives, I’ll cut it into the wire I installed. I’ll put it in the front panel of the machine, and I won’t have to deal with the aircraft switch.

I got all this junk done, turned the machine on, put an oscilloscope probe on it, and got a signal! I was thrilled to the marrow. I got square waves, triangular waves, and sinusoidals. I got big ones, small ones, fast ones, and slow ones. The bizarre “sweep plugin” module that came with the generator worked, too. I don’t know what it is, but it changed the waveform. I still have one knob which is frozen, but at my age, that’s to be expected.

So now I have a huge signal generator which can probably be replaced with twenty dollars’ worth of modern parts that take up ten square inches. I don’t care. It was fun to get it running.

If you’re still reading, here is the payoff.

1. If you repair electronics, use a current limiter when you turn them on. Don’t be stupid like me. I have a variac and a light bulb limiter, and I still decided the best option was to hit the switch and pray.
2. You need a metal Japanese solder sucker. Don’t bother with the big plastic ones. It’s an “Engineer SS-02.”
3. A 6/10A fuse is really a 600 mA fuse.

I still have to fix my old Hitachi oscilloscope. I don’t really have to; I could throw it out. But I should fix it. It could come in useful some day.

My definition of “useful” is unusually broad.

I realize my life is full of excitement and adventure. Try not to envy me.

Geppetto’s Folly

Tuesday, January 10th, 2017

In the Future, not all Robots Will be Helpful

My Arduino studies are still progressing.

As I wrote in earlier posts, I got myself an Arduino UNO, and I started learning to program it. I went to a website belonging to a person known as Ladyada, and I began working my way through her tutorials. I’ve run into a few snags, so while I haven’t stopped, I’m not moving as fast as I would like.

To program an Arduino, you have to write in a language which is either C or C++. If you’re wondering which it is, so am I. The Arduino website says, “the Arduino language is merely a set of C/C++ functions that can be called from your code.” They don’t know, either.

I guess they do know, but I don’t. I have no idea what the difference is, except that C++ came later.

Arduino comes with its own programming editor or “IDE” (Integrated Development Environment), which is a program like a word processor. You write the programs in it, and it can compile them (turning them into software that actually works) and help you debug them. It also helps you lay your programs out in a way that makes them easier to understand. Supposedly.

I say “supposedly” because it doesn’t really do that. At least it doesn’t seem like it. When you write computer programs, you make long lists of procedures and statements, and they tell the computer what to do. You’ll say things like, “If this, then that, but if this, if this, if this, then that, or else this.” You have to keep track of which “if” goes with which statements and so on. It’s very helpful if the program turns things different colors and indents them so things are clearly identified and so blobs of text that go together are clumped together visually. Arduino doesn’t seem to do this very well.

While I was using it (and getting confused), I remembered my ten minutes of college programming experience. I programmed in a language called Pascal (so named because computer science students are always under pressure – I kid), and I used a program called Borland Turbo Pascal. My dim and unreliable recollection is that Turbo Pascal did a very good job of coloring and clumping. I figured there had to be something similar out there (free) for C/C++, because the human mind’s ability to keep lines of code straight hasn’t improved since I took that course.

I found Turbo C++, which is apparently Borland’s C++ equivalent of Turbo Pascal. Sadly, when you run it, it takes up the entire screen, so you can’t move stuff to Arduino and upload it to your board.

I started looking for other stuff. I already have something called Dev C++, but it didn’t make me happy. I found Visual Studio, which is a free Microsoft program (free for hobbyists), and I decided to try that.

Visual Studio takes about a month to install. I believe that’s because it’s a huge program you can use to create your own version of AutoCAD or just about anything else. I was planning to use it to make three LED’s flash on an Arduino board, so maybe it was overkill. It took quite a while to figure out how to make it run, and when I did, it didn’t look too promising. People swear by it, though, so I plan to keep trying a while longer.

The tutorials themselves turned out to have a major flaw. The instructor asked students to write a program, and then way down the page, after it was all over with, she said the program wouldn’t work.

I learned this after trying to make it work. For several hours.

This is not the best way to present a course. When a problem has no solution, you really want to tell people up front.

It’s not surprising that a STEM instructor would do this. When I was in school, they did it all the time. They would give us integrals that diverged or problems the professors couldn’t solve, and they wouldn’t tell us until we had pulled all-nighters failing to find the answers.

The lesson I learned from this is to read the whole page before starting to write anything.

I’m starting to realize I need to think a lot about C (or C++) itself as I learn this. It’s not enough to take the little bits Ladyada provides and extrapolate. You have to know more than that. What’s the correct punctuation (or whatever) for an if statement? Can you read the state of a pin powering an LED to tell whether the LED is on? Things like that. If you start guessing, you end up with problems.

Arduino uses integers to label pins on the board. I don’t get that at all. If “int SwitchPin = 2” means the second pin is named “SwitchPin,” then doesn’t any integer you set equal to 2 become tied to that pin? I have no clue. Very confusing.

I’m going to have to go back and forth from C++ to Arduino to figure everything out, and I guess I should join the Arduino forum. I really hope it’s not full of snotty nerds.

I’m trying to come up with a strategy for writing programs. I think it’s best to start by writing a plain-language version of every program first. “This program turns an LED on if it’s off and off if it’s on.” Stuff like that. Then I can break it down into necessary steps, and then I can think up ways to say it in C++. Maybe that will be helpful.

Every mission needs a statement.

I still want to build a self-balancing robot, because they’re cool. I started looking into ways to build a robot that balances on one wheel or ball, and that got me to gyroscopes. Thanks to Arduino, I now know how gyroscopes are used to make rockets fly straight. You can go to Youtube and see the actual gyroscopes that made V2 rockets fly straight on the way to England.

I’m kind of hung up now, because I can’t decide between a kit and buiding a robot from scratch. A kit would get me past the relatively boring tasks of choosing parts and making components by hand, but it might push me into an area where I mainly turn the robot on and off instead of learning how it works.

It would be neat to make a robot that goes from one room to another and bothers people. You record a message into it, and then you send it across the house to your wife to say, “Bring your man a beer, pronto!” I’d need a really brave volunteer to try it out, though.

On a more serious note, though, I am disturbed when I think about the power machines will have in the very near future. As I check out the things very ordinary people with little training are doing with Arduino, as well as the crazy things well-financed organizations are doing with sophisticated electronics, I realize we are on the cusp between two ages: the age in which men were more capable than machines, and the age when machines will be more capable than men.

Some people worry that machines will become self-aware and then try to exterminate us. That’s silly. There is no reason to think electronics will ever be self-aware. The fact that something reacts to external stimuli doesn’t mean its aware, unless a TV is aware when you push a button on your remote. Machines won’t be aware. But they will act as though they were, so the future still looks pretty scary.

Right now, I get calls from robots that argue with me. If this hasn’t happened to you yet, get ready, because it will. They call and ask you something which is obviously intended to smoke you out as a sales prospect, and something tells you you’re not dealing with a human being. You ask, “Are you a human being?” The robot pauses, laughs, and says, “I’m a real human being.” It has been programmed to say that. Then you say, “Can you say ‘God Bless America’ for me?” Then the robot is stumped. They don’t program them to do things like that.

I offended a legitimate caller the other day. She happened to have a voice that sounded too perfect, and I thought she was trying to sell me something. I started telling her I didn’t talk to robots. She argued with me, so I asked her to say ‘Gerald Ford.'” I like tormenting robots. To my amazement, she said it. Then I had to apologize. Unfortunately, she had never received a call from a robot, so she assumed I was crazy when I told her what was going on.

A good sales robot can get through several sentences without giving you conclusive proof it’s a machine. That’s remarkable. If they can do that in 2017, think what they’ll be able to do in 2025. It won’t be too long before it will be impossible to tell a robot from a person, without considerable effort. Eventually, it won’t be possible at all. Then we’ll end up in a Blade Runner scenario, where an average person will never be sure what he’s dealing with.

Robots already have superhuman processing speed, and in the future, we will be able to give them superhuman physical speed and agility. They’ll be able to move around. They’ll be stronger and faster than we are. They’ll be able to predict what we do. They’ll do our jobs–even complex ones–better than we do. They won’t hate us, because they won’t really have awareness, but they can certainly be programmed to react as though they hate us. From outside, a being that mimics awareness perfectly might as well be aware. We could find ourselves dominated and abused by machines we don’t have the brains or strength to fight.

In the movies, we get around this with ridiculous bits of code saying things like, “Never harm a human being.” That’s beyond stupid. If we have to rely on code–and we do–we’re in trouble. Look how much malicious code there is right now. Do you think things will be different when machines become autonomous? Why would they?

If the human race lasts long enough, we will eventually see people sentenced for programming robots to hurt or kill their owners. It’s inevitable.

There are a lot of malicious people in the tech arena. Right now, they program machines to do evil. In the future, they’ll be able to program machines to program machines to do evil. When that happens, we will be removed from the loop and the problem will be self-sustaining and self-augmenting.

Nikola Tesla predicted that wars would one day be fought by unmanned machines. He was right, just as he was right about so many other things. But it’s going to be worse than that. It won’t be just war, which takes place between nations. It will be intramural conflict, within cities and nations, between human beings and nationless machines. Won’t that be something?

We will have to delay things by putting restrictions on machines. We always say guns don’t kill people, and that’s true. Computerized machines, however, will kill people. Unlike guns, they’ll do violence without our input. They’ll be like super-powerful pit bulls that have to be penned and detuned. Wait and see. It will happen. But we can’t stay in control forever.

Autonomous machines will be able to shoot people extremely accurately and quickly. They’ll be able to dispense deadly chemicals. They’ll be able to blind us with lasers. They’ll act so fast the cops won’t be able to react. They’ll be like the big nasty drones in the Robocop movies, only much faster. They’ll be able to use weapons that exist today, with skill and speed we can’t match, and they won’t feel pain or have fear. They won’t feel regret or mercy. They won’t be concerned about jail.

I wonder if anyone is even thinking about defensive measures yet. I suppose they are. I guess they’ll be a lot like the machines they’ll have to battle. I would imagine you would need a robot to fight a robot.

I won’t worry about this stuff. I don’t know if the world will last long enough for rebellious machines to become problematic. I’m a Christian, so I expect this age to end pretty soon. In any case, making a primitive Arduino robot that wanders around the house won’t speed up our doom.

Arthur Koestler compared the development of the thinking parts of the human brain, in our species, to the development of a tumor in an individual human being. We have greater reasoning abilities than animals, but our emotions are just like theirs, and our ability to control them is also undeveloped. We develop technology, and then we invariably misuse it because we lack love and mercy. We should not have been surprised when we read about drones shooting video through bathroom windows, and we should not be surprised the first time a robot kills a person.

I never expected life to get this weird. But predicting the future should not be hard for those who can see the obvious.

Here’s to a Cherished American Pastime

Saturday, January 7th, 2017

Lying

Today I spent a little while reading about Chinese TIG welders. A commenter suggested getting a used Miller instead of looking at Chinese, and out of boredom, I went to see what other people thought. Man, it’s disappointing to see unprincipled old geezers bashing China on the forums. What a waste of bandwidth. Talk about “fake news.”

You can’t trust anything these guys say. They lost their cushy union jobs because American workers refused to accept a competitive wage. With the help of bad management, they killed the companies they worked for. Now they sit around lying about Chinese products on the Internet, like that’s going to bring Packard and AMC back. It will never happen. Not even Donald Trump can make us THAT great again.

I have lots of Chinese stuff. Some of it is real junk. No doubt about that. But all of it works, and a lot of it is excellent. The prices are fantastic.

Ridgid tools are very good. They come from China. Dewalt manufactures in Asia. I have no idea where Bosch makes its tools, but I guarantee you, it’s not in Europe or the US. I just got an Chinese oscilloscope which is built extremely well. My lathe is a very nice Taiwan job, and my mill, which works great, was made in Taiwan and assembled in China. My vertical band saw is Taiwanese. There is absolutely nothing wrong with it.

The other day I bought a Shars indexable end mill. I paid about $30. Shars sells mostly Chinese stuff. The end mill is magnificent. An American equivalent costs three or more times as much. Am I going to buy that? Are you nuts? Just so some guy in the Rust Belt can be overpaid? That’s charity.

I tried to find some honest comments on the AHP AlphaTIG 200X welder. It was not easy. Creaky retirees who hate China said a lot of nasty things about it. Had they ever used one? Of course not.

I get it. Old American tool companies make better stuff. SOME old American tool companes. But often they’re no better than Asian, and look what they charge. The welder I mentioned can be had for under $850, with a three-year warranty. If it blows up, the seller pays for return shipping, and then they ship you a new one. A comparable Lincoln or Miller will run you over three times as much. It will do exactly the same thing, no better. It will probably last a lifetime. That’s a plus. No one seems to know how long an AlphaTIG will last. But with the Chinese welder, you save two thousand dollars, and you get into TIG several years earlier because of the price.

At worst, you pay about $280 per year for the fun of three years of top-notch TIG and stick welding. That’s assuming the machine craps out in three years.

People always say, “Wait for a deal.” That’s a great idea. When you’re 25. When you get older, waiting five years for something may mean never getting it. You may die first. Or you may lose years of use you can never get back. If you’re 50, you probably have 35 years left (tops) to use your tools. If you lose five years sitting around waiting for a gift from Craigslist, you’ve lost a seventh of them time you could have spent enjoying yourself. If you’re sixty, it’s a fifth of the time. If you’re retired, you may be losing considerably more.

Here’s how it looks:

1. AlphaTIG 200X: $838, delivered.
2. Miller Synchrowave 215: $2735, delivered.
3. Miller Synchrowave 215, used, from a dubious no-name seller, with no warranty: maybe $1600.

Lincoln prices are right up there with Miller.

If I had to rely on a welder to make a living, I would buy American. No doubt about it. I wouldn’t want to worry about having two months of down time while an importer waits for a part or a welder for me. That could kill a business. But to goof around in my garage, Chinese is fine.

If I had to rely on machine tools or ordinary power tools to make a living, would I buy American? No way. Absolutely no way. American mills and lathes are no better than Asian. I’m not sure American power tools even exist. Where would I find them? I know we still make a few big things, like table saws. I think you can still buy American air tools. I don’t know about drills and grinders and so on.

It would be neat to have a shop full of beautiful American tools from the golden age, but people like me never, in the history of the country, had the opportunity to buy those items new.

I remember looking up the Clausing lathe I bought used, to find out what it had cost new. It was tens of thousands of dollars. No normal American had one of those in his garage in 1965. It cost several times what an average worker made in a year. If I spent that much for a lathe, I would have nothing else.

Aside from that, the Clausing was not that great.

Look at the American tools hobbyists were able to afford back when the big American companies were still manufacturing. Atlas and Craftsman lathes. Flimsy garbage, with tiny capacities. Nobody had a new 15″ LeBlond in his home shop. The closest you could get was WWII surplus.

There are a lot of people who buy old US junk and “restore” it. They’re proud of what they’ve done, and they put pictures and videos on the web. About 95% of the time, when it comes to machine tools, they’ve just repainted tools without returning them to new condition. For example a guy will buy a lathe with worn ways, and he’ll strip it, paint it, and make the feeds work. That’s not a restoration. It’s still junk.

Some kinds of machines can be restored without spending too much. Woodworking tools aren’t very precise, so they don’t have to be scraped and ground when they get old. I have a beaten-up table saw which works as well as it did when it was new in the 1990’s. But lathes and mills lose accuracy with time, and you can’t get it back with a can of spray paint.

I considered buying a “restored” mill from an outfit that scrapes them. I found out it was a bad deal. They scraped a few things, yes, but they kept the old screws, the motor, the bearings…everything you would want to have replaced. The paint looked nice, though. That’s important. You could do it yourself for $15, but never mind.

Human beings love to blame others for their problems. China-bashing is just another manifestation of the inclination. What if American union workers hadn’t demanded unrealistic wages and hadn’t refused to work full days? What if the people who ran companies had been more responsible? Maybe we’d still be selling tools instead of buying them.

The most revered American lathe company is Monarch. They still sell their coveted 10EE lathe. This is a small machine that does extremely precise work. Guess what it costs? Over $100,000. And it’s not even new. They sell refurbs. They buy used Monarchs and put new parts in them. Even the manufacturers can’t afford new American products.

I’m surrounded by China, and so are the old guys who lie on the forums. They use Chinese phones and computers to bash China. Chinese goods are all around us. Why should we delude ourselves and pretend these things aren’t there? If your shoes, your computer, your desk, your TV, your flooring, your wallpaper, your appliances, and half of your American car are from China, why not buy Chinese tools, too? Come on.

Here’s something really funny: Harley riders bash the Asians from dawn till dusk, but Harleys are full of Asian parts. Americans don’t make motorcycle forks! We definitely don’t make the electronics in the bikes.

I may get a welder this year. I don’t know. I do know the China-bashers will make it harder to get solid information.

Wanted: Hunchbacked Lab Assistant

Thursday, January 5th, 2017

Free Swill; Must have Green Card

I feel like I’m reaching a turning point in my evolution from white collar sissy to metalworking technonerd. I’m finally starting to feel like I have almost enough crap.

Back in around 2007, when I started buying tools, I would go out in the garage, hoping to do something, and I would see a big void. No table saw. No welder. No band saw. No nothing! Then I started accumulating stuff, bit by bit. This week, I knew I had made progress, because the 2017 Grizzly catalog arrived, and I didn’t even open it. There is nothing I absolutely have to have, right now, in order to keep from going crazy.

Mmm…Chinese TIG welders…mmm…credit card points…

Sorry.

Today I was working on Ladyada’s Arduino tutorials again, and I opened a new page. It listed a bunch of junk I had to have in order to do the next tutorial. Listed: a tiny push-button switch which can be inserted in a solderless breadboard.

I groaned. My local Radio Shack went Tango Uniform a while back, so if I want electronic parts, I have to drive across town to the electronics supermarket (where I will definitely spend over $75 regardless of what I “need”), or I have to wait for Ebay. Or I guess I could drive to the nearest Radio Shack, but dang, I love that electronics supermarket.

Anyway, I decided to check my stuff just to be sure I didn’t have what I needed. I went to the garage, and in the little drawer cabinet on the wall, I saw a drawer labeled “SWITCHES.”

Yes, I already have maybe thirty switches, not counting the ones I have left over from making guitar amps.

I’m living the high life. I should be in a beer commercial.

DANGER, WILL ROBINSON!

Monday, January 2nd, 2017

Bot of Course

I’m glad I got started with Arduino, because it helped me get back to learning C. It’s moderately enjoyable to learn C without any external apparatus, but somehow it’s more fulfilling when you add a second device (after your PC) at the end of a USB cable.

I’m still going through Ladyada’s tutorials. She can really teach. They say those who can’t, teach, so if you turn that logic around and twist it, maybe it makes sense that she’s an exceptional teacher, because she’s not one of those who can’t. She’s the owner of Adafruit Industries, which is a well-known supply house for tech hobbyists. Her PR blurb descibes her as an “MIT hacker and engineer.” I suppose she is overqualified to teach.

I have learned how to make the Uno print things out and do simple math. Naturally, I find it almost impossible to use the code she provides. I can’t take that kind of boredom. I have to make changes. I suppose that’s a good thing, because if you just copy and paste, all you learn is copying and pasting.

I’m thinking it may be time to build a robot. I guess that seems like a surprising jump, given that I can’t do much of anything with the Uno. But it turns out building and programming a robot is really easy, mostly because thousands of other people have already done the work and published the important parts online. Programming robots is one of the main ways people get good at Arduino.

I started looking at robots, and most of them were horrible. There is an Arduino-brand robot, and it looks like motorized ashtray. It’s a circular PCB with two wheels. I’m sorry; I don’t care how great it is as a teaching tool. I’m not going to be happy teaching an ashtray how to navigate the floor of my office, especially now that I don’t smoke cigars.

I still can’t believe I put dozens of Cubans by the side of the road for the garbage people. Those were some fine smokes. I just looked up the statute of limitations, and I’m safe, so yeah, I bought a lot of Cuban cigars. Take that, coppers. Not that the government cares. I’ll bet no one has ever been so much as fined.

There’s a robot called the “BOE bot,” and “BOE” stands for “Board of Education.” I guess that means it’s overpaid, can’t be fired for incompetence, and teaches kids they should consider being gay. The bot looks pretty boring. It’s sort of a little cart that putts around dodging things and following lines painted on the floor.

Here’s what caught my interest: self-balancing robots. These are robots that exist in unstable equilibria. They balance on two wheels or some other inadequate type of support. Cut the power, and they fall over. They’re much neater than four-wheeled robots because every time you turn them on, they demonstrate the possibilities of modern hobby electronics. Simply balancing and moving around are impressive tasks for unstable robots.

I looked at a bunch of these robots on Youtube. Most involve three flat platforms arranged like a two-story building. Wheels and motors go under the lowest platform. Batteries go on top. Each wheel has its own motor. To do it right, you should use steppers, but people use crappy Chinese hobby motors too.

Determining what kind of robot was best was not easy, because people have posted videos of bad robots during the last year, while others posted videos of superior robots as long as six years ago. My natural tendency was to look at robots which had been built recently, but then I would dig up older videos and learn that better designs had been around for quite some time.

I don’t know why people continue making bad robots. Everyone has Google.

Some of the robots are really awful. They fall down, or they can’t maneuver. Some have wires attaching them to computers. Come on! That’s insane. Who wants a robot that can only walk three feet?

One of the neatest robots is a kit job, and it’s called the “B-robot.” The name alone justifies the purchase. Many self-balancing robots wobble and don’t maneuver well, but the B-robot is nimble and sure of itself. It has an arm, too, so if it falls, it can use the arm to boost itself while it rights itself. Unfortunately, it costs $125, which is like $121 more than I want to spend.

I guess the next version will be the Dude-b-robot.

Why get a kit? Because every robot you didn’t design yourself is really a kit. Even if you make the parts, you’re using someone else’s design, so buying a kit is not cheating in any important way.

When I first learned it was possible to build two-wheeled balancing robots, I was surprised. After I got used to the idea, I started to wonder why I couldn’t built a one-wheeled robot. It could change direction faster. If you can balance with regard to one axis, you should be able to balance with regard to another at the same time. That’s what I thought. Then I checked. Sure enough, it has been done.

In my uneducated opinion, the best type of “one-wheeled” robot doesn’t have wheels. It uses a ball instead. It’s unclear who invented it. Various people seem to be trying to take credit. You put three or four steppers in the base of a robot, and you arrange them so they turn a ball trapped under them. The robot balances on the ball, and it can move in any direction by turning it.

A nut genius in England spent an incredible amount of time designing his own copy of BB-8, the small robot in the new Star Wars movies. A ball bot may have a ball which is mostly contained in the robot’s body, but you can also make a small robot which rests high on the upper hemisphere of a ball.

I guess I should be satisfied with a two-wheeled robot to start, because it has been done a million times, and there is an appreciable chance that I’ll be able to make it work. Ball bots are intimidating.

Once you get your robot on its feet, so to speak, you can start doing mods. You can put sensors on a little “head” at the top so it tracks objects. You can put a laser on top of it and shoot at things. You can put a camera on it. You can add a cup holder. You can add various types of displays. You could send the robot to your wife with a display reading, “Help. Out of toilet paper.”

Is it useful? Not in the slightest. At least I don’t think so. But it would teach me a lot without boring me too much.

I hesitate to put this in print, because some idiot may think it’s a great idea, but I believe you could use something like this for home defense. It’s possible to blind people with lasers. It works so well, it’s considered a war crime. You could send a robot out into your yard to shoot lasers at the faces of violent intruders.

I’m not suggesting you do that, because it’s vicious idea, but I suppose it would work. I don’t know how easy it is to get a laser strong enough, or whether it could be carried on a robot a person could reasonably be expected to build at home.

On the whole, I still prefer sharks. Call me a throwback.

It would be neat to make a robot that tracks balloons and shoots them with a laser. That’s actually possible.

I don’t know. There must be some use for these things.

Perhaps for now I would be smart to learn simpler things. I’m having delusions of grandeur.

I may have to trim my expectations, but there is no reason why I can’t build some sort of reasonably interesting robot. If I succeed, you will know all about it.

Wile E. Coyote had Nothing on Me

Friday, December 30th, 2016

Latest Arrival From Acme

The new oscilloscope arrived, and I have had several major triumphs.

1. I managed to turn it on and make it work.

2. I figured out how to get a bunch of downloaded Arduino sketches into the Arduino program.

3. I managed to edit the downloaded files to work with the version of Arduino I have.

4. I succeeded in building a breadboarded adaptor that allows me to put the Arduino’s output on my scope screen.

As I mentioned in an earlier post, Tektronix distributes a set of Arduino files that turn an Uno into a signal generator. I found the files and downloaded them, and I figured out how to get them into the machine. Problem: the first one I chose would not compile.

I got an error complaining about a C type called “prog_uchar.” I got “prog_uchar’ does not name a type.”

I thought I was missing a library, but after Googling around, I learned that prog_uchar comes from an earlier version of Arduino, and it doesn’t work in later versions. I had to replace it with “const char.” Okay, fine. It worked. I’m pretty impressed with myself, since I don’t really know C.

I love the scope. I thought it would look cheap, but it’s very nice. Solid and businesslike. The screen is gorgeous. I love the way it just tells me frequencies and voltages instead of making me do math. The fan is a little loud, but as you would expect, there are online guides to installing better fans.

I have felt conflicted about hacking it. When I ordered the scope, I didn’t realize the hack would essential turn the scope into a more expensive model. I have been thinking it over. On the one hand, it seems a little shady. On the other, they sold me this thing, and I feel like I should be able to extract whatever potential it has. People hack car computers all the time to make them run better.

Anyway, for now it’s great. It’s nice to get one toe into the 21st century.

After using my balky old Hitachi, which weighs maybe 25 pounds, it’s a real luxury to us a 10-pound scope which does what you tell it to. The probes are easy to attach. They’re already adjusted. It’s like going from a Heathkit computer to a Fat Mac.

I got to use my super-cheap bulk resistors and capacitors on the breadboard between the Arduino and the scope, and that was nice. I found out the skinny leads on the cheap resistors work for breadboarding. That was a relief. They’re not ideal, but they serve their intended purpose, which is to allow me to do things requiring resistors when I don’t have top-quality versions of the values I need.

I will try to get through the exercises now. It will be neat to know what a few of my new buttons do.

Is This How Dr. Nefario Got his Start?

Thursday, December 29th, 2016

Molto Bene

My world of perpetually entry-level technology and engineering gets more interesting all the time.

I bought a digital storage oscilloscope. I will need to learn how to use it. I found out Tektronix (a top-level oscilloscope maker) has published a series of exercises designed to teach people how to use DSO’s. The exercises require an Arduino board. I bought one today.

I sort of glanced at Arduino a year or two ago, but I never got into it. It sounded like cheating. I wanted to learn how to design circuits from the ground up, and that’s not how Arduino works. They supply you with a prefab board you can program. I was offended! I thought I should learn electronics so well I could build whatever I wanted out of the drawers at Radio Shack.

I now think I was stupid. Designing circuits from individual components is not simple. It’s probably best left to real engineers. And aside from that, real engineers don’t build everything from resistors and capacitors. They use integrated chips which contain a whole lot of ready-to-wear circuitry. I think getting into Arduino would be a good idea, unless I want to create my first complex circuit when I’m 80.

What is Arduino? Glad you asked.

I don’t know a whole lot about it, but the idea is that a company in Italy sells you a board with a microcontroller and a USB port on it, and they tell you absolutely everything about its design and how to use it. In other words, it’s “open source.” Then you use C to write programs for the microcontroller, and you use the board for projects. There are additional boards called “shields” that snap into the main board, and you can build circuits that are more complex.

You can download a free program that allows you to write code for your boards. You connect them to your PC using USB.

It’s pretty cool, and I am hoping it will also be a gateway to bigger things that don’t require me to be dependent on Arduino.

“Arduino” is a hard word to type. The letters don’t seem to follow each other naturally.

I learned some stuff which may be even cooler than the Arduino stuff. If you use Arduino boards, you will shell out at least five bucks per board, even for Chinese clones, and they take up a fair amount of space. There’s an alternative. There is a family of integrated circuits called “ATTINY,” and they’re the size of op amps. If your project is simple enough, you can program an ATTINY and move your project to it. You can start on an Arduino board and move to an ATTINY.

This is remarkable. I’m talking about a chip the size of a Tic Tac.

Here is the bad news: it’s hard to get an Arduino board without resorting to mail order. Radio Shack sells them; good luck finding a Radio Shack within 20 miles in 2016. If you live in a city full of educated, cultured people (i.e. not Miami), you may be able to find other sellers, but in my area, you are better off shopping for churros, women’s stretch pants that display every possible crease and contour of the pelvic region in minute detail, or really fancy tire rims.

I shelled out $25 for an Arduino Uno board today, and that’s a lot of money for what you get. When you buy the original Arduino stuff, you’re actually making a donation to the Arduino movement, so it’s overpriced. I didn’t feel cheated, though, because it seems like a worthy cause to me. If you buy clones, you’re not hurting anyone, because there are no patents, so if I ever need more boards, China, here I come.

I ordered a few ATTINY’s because they’re so cheap. I plan to play with them eventually. I would love to create a digital tachometer for my drill press. I would be the boss nerd of my whole block.

I don’t promise all of what I wrote is correct. But it could happen.

My studies with the Radio Shack Electronics Learning Lab are zooming along quite well. Now that I’ve given up on the idea of writing reports, I’m flying through several projects per day. It was a good move, because it would have taken me a year to do it the other way. Whatever I lose in depth of study, I more than gain in progress from concept to concept.

Today I get started on doing something or other with the lab’s digital display. That’s pretty cool. In my mind, electronics can be separated into two categories: stuff that has alphanumeric displays and digital components, and all the other stuff. That’s probably not quite right, but it’s how I see things. To me, making the leap from stupid circuits that turn LED’s on and off to circuits that put numbers on an LCD screen is a very big deal. It’s a jump from 1920 to 1975. It’s a jump to a realm which includes nearly every interesting electronic device a normal person owns.

You would think a Radio Shack product with the phrase “Learning Lab” in the name would be a kid’s toy, but it’s not. It’s very useful. If it included an oscilloscope, it would be considerably more advanced than the equipment I used in my first college electronics class.

One of the great things about it is that all the things you need for a whole series of projects are included. You can teach yourself electronics using a powered breadboard and your own components, but amassing the materials will be a giant pain in the butt. The cost of the Learning Lab is way more than offset by the grief it will save you.

Unfortunately, you can’t have one. They don’t sell them any more. But there are similar products out there. And you can find them used on Ebay.

The only problem with the lab is the analog meter on the board. I don’t use it. I use a Fluke meter which works better and is harder to blow up.

I guess I’ll fire up the Arduino and try to figure out how to use it. If all goes well, I should have a working minion by Tuesday.

There’s no Need to Talk About It

Wednesday, December 28th, 2016

I’m Old Enough to Scope it Out and Keep it Loose

Sorry for the really obscure Amazing Rhythm Aces reference.

I have done the unthinkable. I have replaced my Bronze Age Hitachi oscilloscope.

To be more rigorous, I have SUPPLEMENTED my Bronze Age Hitachi oscilloscope. I don’t plan to throw it out, but I got a new scope which will probably see more use.

I got the Hitachi because I was nostalgic for the days when I used to be intelligent, i.e., the days when I was studying physics. I took two electronics courses in college, using Tektronix scopes, and when I decided to revive my interest, I found a creaky Hitachi offered for fifty bucks (maybe it was seventy-five).

My college electronics courses were truly, truly useless. I’m not sure why they bothered. They took the physicist approach, and physicists can’t do anything. If you want to know where an electron in a certain type of potential is likely to be at a certain time, a physicist can help you, but if you want to design a simple headphone amplifier, you might as well hire a bartender. Physicists learn nothing which is of practical use.

My first course was full of calculus, and it centered on the theory behind simple electronic components. We built ridiculous things like differentiators and integrators. When was the last time you went to Best Buy to look at a new 55″-screen integrator? Never! People don’t use integrators. They use stereos, computers, and smartphones. I didn’t learn how to make one useful thing.

My second course was called “advanced,” but it was about things like shining a UV light on a piece of metal and counting the electrons that left its surface. I’m sure Samsung pays top dollar to designers who can count electrons.

Say what you will about engineers. They may be creepy and scary, but they can actually do things.

The Hitachi was useful when I built guitar amps. I used it for monkey jobs, such as finding out how far a signal went in a circuit before being cut off by one of my wiring mistakes. You can’t do that very well with a multimeter. You need a picture, because AC signals on multimeters don’t tell you much.

Unfortunately, the Hitachi is an analog scope, so it doesn’t tell you anything. It just gives you a picture of the signal. If you want to know the voltage or frequency, you have to work it out with a calculator or multiply in your head. Up-to-date nerds use digital scopes. They have little readouts on the screen, and they tell you stuff about what you’re seeing. They also store information so you can look at signals later.

I don’t recall whether the Tektronix scopes I learned on were digital or analog, but given the era, I would guess that they were analog.

You can go on Ebay and get old digital scopes from American companies for not too much money, but they have certain parts that tend to blow, and you may or may not be able to fix them. Also, the cheap new Chinese scopes have more features. I decided to go Chinese.

The Chinese oscilloscope game is quite interesting. There are a number of companies that make scopes that look pretty much alike, and it seems like every budget scope costs exactly the same amount: $400. But it gets complicated. Some scopes are built well, and others aren’t. Some scopes can be hacked, and others can’t. You have to shop carefully.

The scope I got is rated for 50MHz, but here’s something interesting: the frequency is limited by software, not hardware. In other words, the manufacturer makes a scope that will work fine at 100MHz, and they program it so it only goes up to 50 so they can charge less for it. Weird. Naturally, nerds have found the hack that restores its full capability, so once I hack my scope, 100 MHz will be well within range.

There are other hacks for oscilloscopes. I don’t know what they are. I do know that the big drawback to low-end Chinese scopes is crummy software. They tend to have bugs that pop up, and people complain, and the manufacturers have to come up with solutions. It’s my understanding that American scopes are less buggy, which is one reason they cost four times as much.

It will be a little weird, turning on a new scope that does what it’s supposed to do, without requiring a nurse or a shaman to make it function. I haven’t had that experience in well over 20 years.

I found a neat resource: the forum at Eevblog.com. This is a website started by an Australian geek named Dave. I tried another forum, but the people were just a little too obnoxious. I don’t know why electronics turns some people into the fat kid from Pee Wee’s Big Adventure, but it does.

Dave’s videos are neat, too. He’s a real engineer (someone who gets paid to do electronics), so he knows a few things, and he spills his guts regularly on Youtube. He takes scopes apart, which is nice. I decided to get a Rigol DS1054Z largely based on his dismantling video. The scope looks a little “Hello Kitty” on the outside, but on the inside, the build quality is very impressive.

Will I ever need even 10% of the scope’s capabilities. Not this year. Well, that means not in the next three days. Okay, not in 2017. I think. But who knows what I’ll be doing in 2018? Can’t hurt to plan for the future. I would really love to learn a little about digital circuits, and you need a digital scope for that.

The Hitachi’s problems appear to be fixable, and I feel obligated to try a repair. On the one hand, it’s practically worthless even when running normally. On the other hand, it’s a sophisticated, top-quality instrument that must surely have cost over a grand new, so it seems a shame to turn it into a parts cadaver.

Why didn’t I fix it before buying a new scope? First, I am lazy, and I like to buy new stuff. Second, I was really dreading fixing it. Third, when you need to fix a scope, one of the things you should have on hand is…a scope. That works. I should find the Rigol useful while operating on the Hitachi.

I can’t figure out what “Eevblog” means. I believe “vblog” is Australian for “vlog,” but what’s “Eev”? I saw something indicating it means “electron volt,” but if that’s true, what does “eV” mean? Short answer: it means “electron volt.” “EE” means “electrical engineer.” That still leaves “v” to be dealt with.

Well, my brain must have been short-circuited. The “V” is from the “vblog” part, not the “EE” part. Okay, so it’s “EE Vblog.”

Australians. Whatever.

I remember Dice Clay wondering aloud whether we do nuclear testing there.

I think we do.

If I get the Hitachi to function, I will almost certainly write about it here. You have been warned.

User Error

Wednesday, December 28th, 2016

You Have More Control Than You Think

I’m a little reluctant to testify about things that could still go wrong, so I have been sitting on something for a few days. I feel like it’s safe to write about it now.

I have been exposed repeatedly to someone who has a persistent cold. I hate colds. I’m pretty sure I had one long cold from the time I was born until I was 12 years old. I was sick a lot, and it made me miserable. I hate the snot. I hate not being able to breathe or sleep. I hate it. I hate it all. I did not want to get another cold.

Over the last couple of years, I’ve had tremendous success, speaking defeat to various problems. It sounds crazy, but it’s very Biblical. For instance, Jesus told a tree, “May you never bear fruit again.” It dried up promptly. Jesus followed up with a famous saying which has not worked very well for Christians since he died: “Assuredly, I say to you, if you have faith and do not doubt, you will not only do what was done to the fig tree, but also if you say to this mountain, ‘Be removed and be cast into the sea,’ it will be done. And whatever things you ask in prayer, believing, you will receive.”

If you have a problem you can’t solve, you can say, “I speak defeat to [insert problem here] in the name of Jesus.” You have to have faith, and to have faith, you need to pray in tongues habitually. If you do it with the right preparation, it works surprisingly well.

Every day, I’ve been speaking defeat to this illness.

On Saturday, I started to feel strange. I felt the beginnings of pain in my bones. It was as if someone had draped a shawl over me, and everywhere a shawl would have touched–my outer arms, my shoulders, the back of my neck, and my head–I felt an ache starting up. I continued speaking defeat and looking for problems in my mindset or behavior that might open doors.

I started sweating, like a person whose fever was breaking. The pain went away. I never developed congestion or a runny nose. My throat didn’t get sore. It’s Wednesday, and I’m still fine.

I can’t say I have had no problems at all. For several days I had a strange sensation, as if I were enveloped in a cloud of someone else’s anger. I felt like something wanted in, and it was angry because it was forced to stay outside. I had problems sleeping on Saturday night.

One day my nose ran a little, but I had just sprayed a really filthy bathroom (not mine, I hasten to point out) with bleach. You can imagine the fumes I breathed.

Many of the emotions and drives we think are our own come from spirits. I know that for a fact. I remember walking into the National Holocaust Memorial and being overwhelmed by the grief of the Holy Spirit. It’s very common for mentally ill people to hear voices telling them to kill people they are not angry at. They kill their mothers, spouses, children, random strangers…the anger comes from somewhere else. One of the greatest rock and roll drummers shattered his mother’s skull with a hammer because voices wouldn’t leave him alone.

The fruit of the Spirit come from the presence of the Holy Spirit, so presumably, many of our viler drives come from loser spirits causing problems on their way to burn for eternity.

We have come to accept illness as normal. I don’t think it is. I think you get more power over it as you give more power over yourself to God.

David wasn’t well when he died, and Elijah died from an illness. We know Timothy had health problems because Paul said so. Does that mean we have to be ill? I don’t think so. Elijah made mistakes. He had to run from Jezebel because he ridiculed the prophets of Baal. Timothy probably made mistakes, too. We don’t know how many of the apostles’ problems were caused by their own errors, but surely many were. The Bible never holds any of them out as perfect.

A couple of weeks back, I looked into making a buffer arbor for my belt grinder. Every tool person needs to be able to buff things. I got on the web and looked into buffer safety. I found out buffers are extremely dangerous. A well-known knifemaker was killed by a buffer not too long ago. It grabbed a knife out of his hand and threw it into his heart. Buffers are scary.

I asked buffer users for advice. I wanted to know whether buffer accidents were inevitable or just the result of user error. Everyone agreed that buffer accidents are caused by bad practice, not some insurmountable characteristic of the machinery.

“User error.” That’s the phrase people use. If you run your hand through a table saw because you’re too cocky to use a push stick, it’s user error. It’s somewhat dishonest to call it an accident, because if you adopt bad practices, you almost assure that a disaster will occur eventually. If you willfully expose yourself to an avoidable risk, is it an accident when you get hurt? Not really. You consented. You ordained it.

I bring this up, because I have been thinking about it in connection with the problems we have here on earth. I believe most are the result of user error.

To make things more confusing, let me bring in the concept of inheritance.

The Bible says a righteous man builds up an inheritance for his children’s children. We always assume this refers to wealth. The truth, though, is that the best thing you can pass on to people is knowledge and wisdom, and that is most true of knowledge and wisdom concerning God.

Think of the way earthly inheritance works. Somewhere in a family’s line, a person who has nothing finds out how to get wealth. He works hard. He suffers. He has setbacks because of his ignorance. When he is old, he passes his wealth on, and his children don’t have to suffer as much or work as hard as he did. They do better than he did in life.

Knowledge and wisdom are supposed to work the same way.

People in good families pay attention to their kids. They don’t let them grow up untended, like weeds (as I did). They teach them how to do well and avoid pitfalls. God is a father, and he is a good father, not an inattentive or selfish one. He wants us to have knowledge and wisdom so we can avoid unnecessary suffering. He doesn’t want us to repeat the stupid mistakes our parents made.

When you learn about tool safety, you’re inheriting wisdom. The first guy who was hurt by a buffer probably didn’t have anyone to warn him properly. Ever since then, knowledge has accumulated, largely because of accidents in which people have been maimed. If you inherit the wisdom others accumulated with great suffering, you can make yourself safe. If you refuse, you get hurt just like they did, and you bring it on yourself.

When we suffer diseases and other setbacks in life, very often, it’s the result of user error.

The church rejects a huge percentage of the inheritance Jesus died to bring us. We reject prayer in tongues. We reject communion. We reject the fruit and the gifts of the Spirit; we feel we have to change ourselves. Like people who reject inherited money because they have the fantasy that they can be “self-made,” we want to make ourselves holy and earn God’s help.

We want to earn gifts. How is it a gift if you earned it?

We are supposed to be the earth’s nobility, and nobility comes through inheritance, not effort.

Healing and other helps from God are connected to confession, repentance, and obedience. Does this mean we earn his help? No, it just means we cancel it out by opening doors to the enemy. When you lie to God and pretend to be righteous, and when you habitually disobey him, you give other spirits rights. You drive the Holy Spirit out by dishonoring him. If you want the promises of the Bible to work, you need to make communion often. You need to admit that you’re responsible for the sacrifice of Jesus, and that you’re a taker, not a giver. God doesn’t owe you good things, and you need his help to control your flesh.

I still remember my friend who died from cancer. Everyone in my church kept telling him he was healed, but people got very angry when I said we needed to confess and get rid of sin and pride in order to close doors to disease. My friend was arrogant. That was just his nature. The church reinforced that. Now he’s dead. We invited God in one door and the devil in through another. God doesn’t like to share. He is “God,” not “a god.” He has to be given special honor.

One of the greatest things about having a good relationship with God is seeing other people inherit through me. There are a handful of people who have listened to me when I talked about things God showed me. Now sometimes I learn from them. They got things flowing, and they hear from God directly instead of waiting for me or some other human being to tell them things. That’s how it’s supposed to work. They will have better lives than I did. They will inherit instead of working. They won’t have to build up the same little stash of wealth that I did, all over again.

The church gave away inheritance a long time ago. Every generation starts over, in the dirt, and we die spiritually poor. If God manages to get some knowledge into someone, we ignore or murder that person. We don’t heal the sick very much. We only rarely raise the dead. We make the promises of the Bible seem like lies, because we rejected the knowledge that makes them work.

I’m very, very glad I’m not sick today. That’s all I can tell you. I can’t force people to listen or benefit. I plan to keep going forward, even if everyone I know dies in defeat.

I hope I don’t wake up tomorrow with a cold. That would be embarrassing.

Keep praying in tongues. Keep taking communion, with an emphasis on confession, repentance, and admitting you need help. Keep speaking defeat to pride and self-deceit. See what happens. It certainly beats giving a fifth of your paycheck to a white-trash liar in a purple suit.

Notes From the Grinch’s Workshop

Sunday, December 25th, 2016

No Roast Beast This Year

Christmas has not been bad. It’s just me and my dad now, but life is peaceful, and my relationship with God is rewarding.

I don’t hear from my other relatives much. My sister is not really part of the picture now, and the others just don’t contact me often. It’s always about business when they do. I guess I offended them in some way, but I don’t know what I did. My grandfather left a screwed-up estate, and that tends to create alienation among relatives, but I have never taken a dime or a single article I wasn’t entitled to, and the only time I offered to work for the estate, I refused to charge. Oddly, they chose a cousin who took 33 percent of the proceeds of his work.

Could have saved each one of them thousands of dollars. Whatever their reason for turning me down was, it must have been compelling. Or maybe they just didn’t think it through.

I did hear from one aunt. Her relationship with the others is not great, but I don’t have any problems with her. She was upset because Obama jabbed Israel in the eye, refusing to oppose an anti-Israel UN resolution. She believes God will punish the US because of it, and history appears to show that she had good reason to be concerned.

For years, Democrats ridiculed people who said Obama had problems with Israel, but at some point during his administration, the gloves came off, and now people admit he’s Israel’s enemy. No apologies from the apologists, however. No admission of error.

The Bible predicts that God will start defending God personally when all the nations of the world turn against it. Has that happened, with the UN resolution? I’m not sure. We elected Trump, and he appears to be a rabid Israel fan. Ordinarily, you would think that would count for something. But he got fewer votes than Hillary Clinton, an enemy of God from the word “go.” That counts for something, too.

I am not worried, because worry is wrong. Besides, my relationship with God is going very well, so I don’t expect to suffer as badly as other Americans. I’m not all over the web calling the Israelis Nazis and comparing the Jewish state to South Africa. I hope as many people as possible get it together and stop provoking God, but I’m glad I’m withdrawing from the mass of ignorant people who are doing their best to bring on disaster.

The day was productive for me, by my standards. I spent a lot of time organizing and moving useless items into places where they will not be in the way as much. I spent some time reading an old quantum mechanics text, and I watched a quantum mechanics lecture on Youtube. I did a couple of simple problems. I am trying to pick up bits of the knowledge that leaked out of my head after I quit graduate school.

I also spent time with my handy-dandy Radio Shack Electronics Learning Lab. I have been going through the projects and writing up lab reports, because reports help you learn things, but the more I got into it, the more I felt it was counterproductive to write things up. The material in the workbook does not lend itself all that well to report writing, and writing slows the process down by a factor of maybe ten. I started going through the book assembling and dismantling the projects one after the other, without writing anything. It seems to be the right way to do it. If I really feel the need, I can write about certain subjects, but I believe writing about everything will keep me busy until I’m 70.

It’s nice to do things right, but if you overthink and do them TOO right, you fall behind and never get anywhere. I wish I had understood that when I was in grad school. I felt like I had to understand everything, backward and forward.

I’ve been fiddling with the test equipment I own. I found out I don’t have a cord for my ancient HP signal generator. The resulting kerfuffle is really something. A thousand years ago, when it was made, they used a connector called the PH-163 or Belkin 17952. It’s sort of like a modern computer power cord connector, but it has oval pins. In 2016, a PH-163 cord will run you thirty bucks, not including shipping. Forget that. I ordered a male PC connector, and I’m going to rip the old connector out of the box, carve up the sheet metal, and put the new one in. I don’t even know if the signal generator works, so I’m not going to Sotheby’s to bid on a priceless antique cord for it.

My old Hitachi oscilloscope has a messed-up volts/division knob on one channel. It’s very hard to turn, as if someone put glue in it. I tried running Kroil into it, but it didn’t loosen it up completely, so I guess I’ll have to dismantle the scope and take a look at the pot/rotary switch/whatever behind the panel. I have no idea whether it can be fixed.

I’m also getting a funny display when I check the square-wave calibration function, and from what I’ve read, that means parts on the PCB have to be replaced. Fun, fun, fun. I don’t know how much effort I want to put into a scope that cost 50 bucks, but I plan to see what I can do.

It’s time to get a real scope. That means digital. I thought I might try to get an old Tektronix or HP, but people seem to agree that you’re better off getting a new Chinese job. I may splurge for a Rigol DS1054Z. They get raves. It would be nice to work WITH a scope instead of working ON it.

When people talk about the old scopes, they say they do most of what the new ones do, and the quality is better, but they also say this part burns out and that part quits working, and then you either have to become an oscilloscope technician or buy another one.

I don’t know much about it, but it looks like you can hit Ebay and pick up a 20-year-old scope that does what a modern Chinese one does, for maybe 40% less than Chinese. But is that a good idea? I saw a technical guy tear down the Rigol, and it’s no Alibaba toy. It’s built like Kim Jong-Un’s armor-plated underground end-game outhouse.

The Hitachi was fine when I was basically using it to see if I was getting any AC signal at all, without worrying whether the display was correct. I was working on tube amps, and that doesn’t require a lot of precision. I can’t get by with grossly distorted waveforms for the rest of my life. Sooner or later I’ll need to know what a signal really looks like.

I dread opening the box up and looking for problems. I’ll probably have to remove and store thirty knobs to get the front panel off, and they’re attached with microscopic set screws.

One of the big down sides to fooling with electronics is that you have to join forums frequented by guys who have never, ever, for very solid reasons, gotten a date. Some of the people are nice and helpful, but others think that because they’ve spent their entire lives staring at circuit boards and watching Japanese cartoons instead of engaging with human beings, the rest of us should crawl to them on our faces and shower them with offerings of Jolt cola and Skittles before begging their forgiveness for existing.

You really have to finesse them to get what you want without falling into the mud-wrestling pit. You have to know when to say, “Great. Thanks for the information,” when you have received no useful information at all and simply want to end the interaction.

I guess it’s insulting to humor and cajole people you could never respect, in order to get answers out of them, but you can only treat people as well as they let you.

Anyway, it was a pleasant, peaceful day. It would be nice if I woke up tomorrow and the half of my family that died from old age and cancer was still here, and we were all in Kentucky sitting around a Christmas tree, but things are good, and they’re getting better.

Overpriced Resistance is Futile

Sunday, December 18th, 2016

Joy Comes in Bags From China

This week I decided to bite the bullet and go through the projects that come with the Radio Shack Electronics Lab Learning Kit. I bought one when Radio Shack closed a bunch of its stores last year. It’s kind of a neat tool for learning about electronics. Cheap, too.

The lab is basically a breadboard (six columns) with various things you can connect to the components. Built into the lab, there are switches, an analog meter, a buzzer, and other things that can be useful.

I think the best way to do this is to keep a lab notebook and do reports. As a former physics teaching assistant, I should have no problem with that. I have to make up experiments, though, because the stuff in the Learning Lab books isn’t written for people who collect data and do analysis. The writer, a well-known electronics teacher named Forrest Mims III, just wants people to build stuff, see if it works, and move on.

I decided to do things like changing component values and writing small tables. Then I can compare the results with the mathematical formulas associated with the circuits. Short and easy, except when ineptitude gets in the way.

Writing things down is very important when you do anything technical. I say that as a person who doesn’t do it. I have suffered the consequences.

This isn’t the only thing I’ve done to amp up my electronics game. I bought a bunch of cheap components on Ebay. This was a genius idea I should have had ten years ago.

When you build circuits, you’re always in need of this resistor or that capacitor, and if you don’t have them on hand, you have to drive to Radio Shack, drive to a different store, or order the parts online. My local Radio Shack, where I used to shop for parts when I built current and temperature controllers for a professor’s laser diodes, bit the dust in 2015. We have an incredible electronics supermarket in Miami, but it’s expensive and far away. Ordering online is fine, but if you did it for every part in a simple circuit, your build would take six months, and buying one part at a time anywhere is way expensive.

I found some guy selling 1% tolerance 1/4-watt metal film resistors for $15. How many? Which values? Try 2800! All values! Nearly. You get like half a pound of resistors in a huge number of values. I also found great deals on film caps, Chinese ceramic caps, and a few potentiometers in common values. For the heck of it, I picked up some IC’s and sockets. Can’t hurt.

Here’s the rub: the resistors have thin leads. This doesn’t bother me, because I would much rather have a thin lead than wait ten days for a resistor.

The resistors arrived today, and I decided to check one. I was suspicious of the 1% claim. I don’t need 1%; 10% will be fine and dandy. But you want to know what you bought.

I hooked a resistor to a meter and heated it with a soldering iron. The value was 430 ohms. The resistor measured exactly 430, which was way beyond any level of precision I’ll ever need, and it didn’t move when I heated it. SOLD!

Even if the resistors aren’t great, they’ll allow me to build things without waiting, and if I have to, I can get better stuff to replace them in permanent projects.

Caveat: some guy on the web says he scraped the paint off his cheap “film” resistors and found carbon resistors inside. Not that a 1/2-cent carbon resistor that works is a bad deal.

The soldering iron is also news. Twenty years ago, when I got my Weller soldering station, I thought I was the coolest kid in school. I was used to pencil irons that weighed a pound and had to be placed in cereal bowls because they didn’t have stands. I started looking into different irons this year, and I found out my Weller was strictly low-budget.

It turns out you can pay a thousand dollars for a soldering station, and they come with lots of crazy attachments. Also, cheap stations don’t have enough power. They take too long to melt solder, and this can actually screw up your joints.

I thought about getting a Hakko. They’re very popular. But I kept looking, and I found myself a dream come true: the Ersa I-Con Pico. Yes, it has THREE names.

Ersa is a snooty German company (what a rarity), and they make high-end soldering stuff. The station I got is like their Maverick or Vega (remember those?). Still, it’s way better than my Weller or a Hakko. It has a digital display. It pumps out about 80 watts. It gets hot in ten seconds. Best of all, it has a tiny iron a little bigger than a pen.

The general rule with cheap irons is that they’re too long and too heavy. There’s no reason for it, as far as I know. It’s just a fact of life. It can be very hard controlling a soldering tip four inches from your hand. The Ersa’s tip is like two inches from your fingers. Beautiful!

I think this is an example of having a lame tool you didn’t know was lame until you replaced it with something good.

I haven’t soldered anything yet. The package just got here. On Sunday. Amazon is starting to scare me with their newfangled speedy deliveries. I half expect to wake up and hear Jeff Bezos singing in the shower.

In summary:

1. you need a pile of cheap electronic components from Ebay;
2. you need a better soldering iron; and
3. you should really try an organized approach to learning about electronics.

I preach to myself.

One more tidbit: if you have a cheap multimeter and you want to kill yourself because the Chinese probes won’t hold onto anything, spring for some Fluke spring-loaded probes. I finally did. What a difference. I had cheap Chinese ones, and the plastic flaked off until they refused to hold anything. I could have cobbled a solution together, but I bought new probes, and now life is sweet.

I think I may sever the Chinese probes, toss the ends, and attach alligator clips.

With my new soldering iron.

Hmm…I think that might be “cobbling a solution together.”

BTW, I found out how you’re supposed to make shrink tubing contract. They sell miniature heat guns for the purpose. You can buy a fancy “rework station” that includes a heat gun. I think that’s a stupid move, because one part of any all-in-one tool will always break before the rest, and often it can’t be fixed. So there you would be, with your fancy station, a heat gun that doesn’t work, and another heat gun sitting beside it taking up space.

And the new heat gun wouldn’t match the station, which kills the fun of the whole all-in-one ethos.

A company called NTE makes a small heat gun that gets good reviews. I may get one. It’s about $20. I’m tired of roasting my shrink tubing with a lighter.

Hope this is helpful to you. Probably not, though.

Today’s Minor Miracle: Welding Cast Iron to Stainless Steel

Saturday, December 10th, 2016

Explain This if You Can

I welded something successfully today, and I can’t figure out why it worked.

I bought a motor on Ebay. It had a cast iron base. The seller packed it badly, and the possibly resentful USPS people who handled it broke a foot off of it. I got a full refund, but I didn’t have to surrender the motor, and I haven’t found anyone who wants to buy it.

I looked into ways to put the broken bit back on. Ordinarily, people braze cast iron. It’s considered very difficult to weld (adding steel filler to it with high heat), because cast iron expands and contracts differently than welding wire, and the welds tend to pop as the work cools. To braze, you have to heat the part to something like 400 degrees. Then you melt bronze (I think) into it with a torch, and you cover the whole mess with welding blankets while it cools.

No way could I braze this thing, because if you heat a motor to 400 degrees, the windings melt.

You can also TIG weld it, but I don’t have a TIG welder.

I found some guy on the web claiming you can MIG weld cast iron with only a slight preheat–about 100 degrees–using non-magnetic stainless wire. You then “peen” the welds with a hammer or needle scaler to somehow or other counteract the problem with the welds opening. Maybe it expands the weld material horizontally.

It sounded nuts, but I asked around and couldn’t find a better idea, so I decided to try it.

Today I cut shallow v-grooves in the places where the parts met (standard when welding thick parts), and I cleaned them with alcohol to make sure there was no loose graphite on them. Cast iron is full of graphite, and supposedly it contaminates weld filler and causes problems.

I clamped the parts together with a Bessey clamp knockoff and started welding. Naturally I forgot to turn on the gas. The first two tacks were giant blobs that looked like sponges. I ground them down to start over, but I didn’t get all the crap out. Oddly, the welds held, and I was able to remove the clamp.

Someone on the web suggested using high wire feed. That was bad advice. Even after I turned the gas on, the wire spewed into the welds and made more blobs. I turned the feed down, but I never got it low enough to be controllable.

I also had trouble with my mask. I don’t think it darkened at all on the first two welds. I had to adjust it to the darkest level in order to see anything.

I continued making very small welds, peening, and waiting. That’s part of the technique.

When cast iron welds fail, they make a sound like “tink.” I never heard that sound. That surprised me, because what I was doing was sort of a Hail Mary job. I didn’t think it would work.

I got it welded up, and then I spent about ten years cleaning it up with the angle grinder and a rotary tool. A bolt has to go through the motor base, and that means a washer has to sit flat on top of it. The base will sit on a platform, so it has to be flat on the bottom.

Everything went fine, apart from welding very clumsily and making a mess. When it was done, I beat the part with the hammer’s handle, and I tried to pull it loose with my hands. I couldn’t budge it. I think it’s actually welded. It’s probably a D on a scale of A to F, but it’s not going to be under much stress. Maybe it’s not good enough, but I can tell you this: there is no way in hell I’m going to redo it until it fails again.

Because the weld didn’t fail, I’m not sure if I learned anything about welding cast iron. If it had failed, I would have known the method didn’t work. Because it doesn’t appear to have failed, I’m not sure what’s happening. Sometimes really bad welds seem acceptable at first.

Here’s something weird that appears to be true: it seems like it’s possible to weld stainless directly to cast iron, and that would mean it’s possible to build up stainless weld on a cast part. If that’s true, you should be able to coat one side of a part with stainless weld, make a stainless replacement for the other piece, and weld it to the congealed filler. If my weld fails, I plan to try that. Can’t hurt. Hey, it’s a free motor.

I don’t know what to do with the motor. I now have three pretty good motors sitting around doing nothing. The one I fixed is really nice. Maybe I could try to build a 6×48 belt sander. I don’t really need one, but they’re great tools to have. It would be nice to build one and have a disk sander on the side.

I wish I had some cast iron scrap. I’d practice welding it to see if my results could be trusted.

Also, it would be nice to improve the appearance of my welds. When I weld, all I see is arc glare and red metal. It’s blind luck if I hit the joint.

Here’s a photo. It may not look like it, but the welded-on part is aligned perfectly.

New Tool Knowledge

Saturday, December 10th, 2016

Try to Contain Your Excitement

I keep learning things about tools. It’s astonishing how much there is to learn about using the few simple items I have in my garage. People who really know tools must have stores of knowledge comparable to engineers.

A week or two back I created a new handle for my blow gun. Then something happened that required me to switch a tool from one air compressor to the other, and I realized I had a male fitting on the end of one hose and a female fitting on the end of the other. I could not switch tools without switching the fittings on tools.

This one left me scratching my head. Surely there was a right way to do this. Everyone else uses male or female fittings, but not both.

I kept thinking about the pluses and minuses, and I realized female was the way to go. If you put a male fitting on the end of a hose, the compressor will discharge every time you remove a tool. A female fitting will have a valve in it that shuts the air off.

Here’s the question: why did I have a male fitting on one hose? I must have asked about the correct fitting a long time ago, when I got my first compressor. I must have had the right information. My best guess is that I installed a new hose, ran out of fittings, and used what I had. Then I forgot to get a new fitting.

Anyway, whatever the explanation is, here is the answer: put a female fitting with a swivel on the end of your air hose.

In researching this, I also got into the subject of different types of air fittings. I know of three types, offhand: automotive, industrial (I think it’s also called “mechanical”), and universal.

In the past, I never thought about the type of air fitting I was buying. I just assumed they were the same. Then I found out about the different types, and I had a new research project on my hands.

Which is the best kind? NO ONE KNOWS. People do whatever they want. Believe it or not, there are regional preferences. In some areas, you want automotive, because that’s what everyone else has. In other areas, you want industrial.

To make things worse, there are rarer types. Some are supposed to provide superior flow.

A guy on a forum provided a great solution to my problem: universal female coupler and industrial male couplers. A universal female coupler will work with all male couplers. I went to Home Depot last night and got me a universal female coupler.

The replacement hose I bought is a Flexzilla. I agonized about which brand to get, and finally I decided to give Flexzilla a try. It’s bright green, so if you step on it, it will be a choice and not a mistake. It has no memory (I can relate). It’s light. I like it. If I hadn’t gotten a Flexzilla, I would have gone with rubber. Poly is too stiff.

I found out that machining coolants are more complicated than I thought. When I started, I learned to use WD40 on aluminum and Ridgid threading oil on steel, and that was about it. The other day I picked up a fantastic indexable end mill from Shars (where low-budget machinists shop), and I found that the finish varied, so I started looking into the problem. That’s how I ended up reading about coolants.

First, let me say the cutter is great. The big gripe with indexable cutters (cutters with several carbide inserts in the end) is that they give poor finishes due to minor differences in the heights of the cutting surfaces. I cut a piece of mystery steel, and the first 75% of the performance gave me an astonishing silky surface. Better than I could ever get with an end mill. The problem is that the finish got worse after that.

I am not knocking the product. It proved it can do a great job. I recommend cheap Shars indexable end mills. I paid a little over $30 for a 2″ mill complete with three no-name inserts, and it works. Check prices on American indexable end mills and see why I’m so happy.

I was cutting with a light application of Ridgid oil, even though a lot of people don’t use oil with carbide and steel. I read up on it, and I found a couple of sites that said interesting things. First, coolants and lubricants may be counterproductive. Second, it may be possible to grind HSS tools for aluminum that require no lube at all. Two different subjects (aluminum and steel).

One site said that liquid coolants chill carbide edges as they land on them, causing tiny stress cracks. Then the edges break down prematurely. The site suggested that the wear you avoid by using coolant is outweighed by the damage the coolant does. It said something about commercial shops spending 16% of their machining budgets on cooling and only 3% on tooling, which suggests the coolants cost way too much.

I don’t know if it’s true. I plan to throw some steel on the mill and find out.

Another site said clearing chips was the most important part of preventing finish issues. That sounds likely to me. The part I was machining had little swirling scratches on it, and I know they weren’t caused by the inserts. I think they were caused by bits of metal caught under the inserts. If that’s true, then I can get a beautiful finish on steel simply by blowing air on parts as I cut. It will blast the chips out. I think the oil may have made the finish worse by making chips stick to the metal.

A company called Kool Mist makes little devices that blow a mist of air and coolant on parts as you cut. I’m thinking I may get one and omit the liquid. It would blow chips away from my cuts. I’m positive I don’t need anything other than a light squirt of WD40 for aluminum, and it may be that I don’t need any liquid at all on steel.

I read that stainless is too gummy to cut without coolant, so I guess you just have to accept that.

To get back to the HSS/aluminum thing, I find it hard to believe that it’s possible to machine aluminum dry. It’s impossible with carbide in a mill, because the aluminum welds itself to the cutter instantly. I’ve never tried HSS dry on a lathe, but you can get away with carbide, although the finish is bad if you don’t lubricate.

I’m wondering what kind of rake I need to machine aluminum dry with HSS. Maybe I can find the info online.

I don’t think I want to machine that way as a habit, because I love carbide. You don’t have to grind it. Grinding lathe cutters takes a long time. Carbide inserts last forever in aluminum, and you can get a very nice finish. If I start messing with additional HSS tools, I’ll want to get more tool holders, and they weigh about ten pounds each. I feel like HSS is an answer to a problem I don’t have.

Why did I get into this quest? Because I failed at fly-cutting. A machinist I respect told me to fly-cut with high RPM’s, so that’s what I did with my mystery block. The edge of the bit kept wearing down as I cut. I had forgotten this crucial information: he was referring to aluminum, not steel. When I finally did it right, I had to turn the mill at about 100 RPM, which is ridiculous, and the finish was not that great. The end mill flies through work, and the finish is superior. Done deal.

Remember the treadmill my neighbor threw out? Probably not. I have the motor out, and I may want to machine the shaft to take a new pulley. A forum guy warned me about a potential problem. He said that if you take the armature out of a permanent-magnet motor (like a treadmill motor), the magnets will instantly demagnetize, resulting in reduced performance. Like life wasn’t complicated enough. He said you have to put a piece of steel between the magnets when you take the armature out.

This led to more research, and I learned some stuff.

In the dank, dreary past, many magnets were made from an alloy called Alnico (aluminum, nickel, cobalt, iron). If you shake it too much, it loses magnetism. If you drop it, it loses magnetism. If you take an armature out of a motor with Alnico magnets, it loses magnetism. Engineers designed iron objects known as “keepers” to insert in motors to prevent demagnetization when motors (or similar devices) are disassembled.

I found a couple of sites that said that Alnico is history (unless you play the guitar). Now cheap magnets are made from barium-ferrite powder, which can be cast in useful shapes. Barium-ferrite is supposed to be way less snowflaky than Alnico. More than one website told me it does not require a keeper.

The motor I have almost certainly has barium-ferrite magnets, because the next step up is rare earth, and rare earth magnets cost a lot. So I should not need a keeper (not the magnet kind). But the forum guy claims he ruined three treadmill motors just by removing the armatures briefly. So now I’m thinking I should find a piece of pipe and make a keeper, just to avoid the issue.

My small belt grinder has an armature that has been removed, and it works fine. I asked some electronics nerds on a forum, and they claim no keeper is required.

My advice: if you take a treadmill motor apart, use a keeper. Maybe it’s unnecessary, but it definitely won’t hurt, and it will cost you nothing or about two bucks.

What else have I learned? Let’s see. Belt grinders are fine for grinding HSS bits, but the bench grinder is faster, and it’s probably cheaper. Belts wear out fast.

Deburring…I learned about deburring. This means the removal of sharp burrs from metal parts. I have a worn-out belt on my small belt grinder, and I’ve been using it for deburring. It’s fantastic. One or two five-second passes will put a beautiful soft edge on a part. Try it. Don’t even bother with files. They’re for losers.

That’s all the earth-shaking information I have at the moment. I’ll leave you with a video of a guy using an indexable end mill to make a giant steady rest.

New Toys; New Projects

Wednesday, December 7th, 2016

Too Lazy to Post Photos

I have a few things going on in the shop. Figured I may as well write.

First of all, the woodturning tool rest is all finished. I haven’t used it yet, because I am thinking about dust collection, and I haven’t decided what to do about holding the tailstock end of the work.

When you turn wood in a lathe, you hold the left end in a chuck or some kind of spur, and the motor, which is at that end, turns the wood. The right end sometimes has to be supported, too. For that you are likely to use a live center. That’s a thing that has a point or some other grabby structure on the inboard end, to hold onto the wood.

To use my existing tailstock, I would have to extend the wood across the lathe’s carriage, and that would be a pain. I think I’ll make something that clamps in a tool holder. I’ll have to align it every time I use it, but how often will that be?

Dust collection is supposedly impossible with a lathe. You just reduce the mess as much as you can. I don’t have a dust collector. I have a shop-vac, which is made for a different job. A shop-vac makes air go fast in a small tube. A dust collector moves high volumes of air through a bigger tube. This is what I’m told.

Because there is no hope of good dust collection anyway, I think I’ll try the shop-vac. I plan to get a dust hood, which is a flat, rectangular piece of plastic shaped a little bit like a funnel. You aim it at your dust, and you hook a dust collector up to it. I think I’ll rest one of these upright on the lathe bed, with the hose going down through the openings. It should help a lot. At least it will get the big chunks.

I bought a two-tier welding cart, and I learned a lot about this type of product.

When you buy a Miller or Lincoln welder, you get a serious industrial product made in America, except maybe for the strange items Lincoln sells at Home Depot. I don’t know about those. If a cart comes with your welder, it will probably be a dubious item made in China, from Chinese sheet metal.

My welder came with such a cart. It works fine, but it’s not the greatest cart on earth. It’s a little short, so the tank bumps against the welder. Also, the sheet metal could be stronger where the tank sits. There are little locating tabs around the tank base, and they bend easily.

I also have a plasma cutter, which is similar to a welder in size and weight. It didn’t come with a cart. You can screw wheels to the bottom, but then you have a plasma cutter with no area for tool storage, and it’s way down on the ground.

I got an email from Eastwood, the company that sells reasonably good Chinese tools for working on cars. They advertised a two-tier cart. You can put a welder or plasma cutter on each tier, and it holds two tanks. The weight capacity is 350 pounds, I believe. It looked good, but it’s Chinese, so I looked at other products.

I found out that you can pretty much forget about finding a good US-made welding cart. Cornwell makes one (it may be Chinese, but it has Cornwell standing behind it), but they only sell them from Cornwell trucks. I’m not going to chase some guy in a truck. I ruled that out.

There are a zillion two-tier welding carts on the web, and almost all are the same model, made in China, rebadged. The weight capacity is not great, and they get mixed reviews. I decided to give up and go with Eastwood.

The cart arrived, and it took an hour to put together. It had one defective part, but I’m going to make them replace that. Basically, it’s a nice solid design. It has two shelves of fake diamond plate backed up by horizontal supports. The shelves aren’t bulletproof, but the supports are very strong, so the shelves are more than adequate. It has hooks for holding cords. It has tubes for TIG rods. It also has two trays to hold little items like consumables.

It will hold two large gas bottles, and it uses a wonderful system of sturdy steel hoops.

They must have had issues with the rear wheels and axle, because now it comes with a thick steel rod and two very heavy wheels with bearings.

I put my plasma cutter on the bottom and my welder on the top. Suddenly my garage seems twice as big. What a relief. I highly recommend this product. They say welders are supposed to build their own carts. I could not have made anything this nice, and the parts would have cost what I paid for the entire cart. Go ahead and make a cart if you want. I feel like I got a deal.

I would say the footprint of the cart is about 3′ by 2′, so it’s not small, but it will seem small once your welders, cords, and bottles are off of the floor.

In other news, a neighbor blessed me by throwing out a treadmill. I put it on my truck and hacked it apart. I came away with a 2HP motor and a linear actuator. There was also a lot of metal I might have used for welding, but I didn’t have any place to put it.

I am now working on a control apparatus for the motor. My first treadmill motor came with an MC-60 control board, and for that, all you need is a potentiometer. The current treadmill has an MC-2100 board. People on the Internet insist it requires a PWM (pulse wide modulation) input. I found a schematic for a simple add-on circuit, and I’m waiting for the parts to get here.

I’m thinking I’ll make a mandrel with a 1″ shaft and make myself a two-buff variable-speed buffer. Do I need one? OF COURSE. What don’t I need?

I did some research, and it looks like you want 5000-9000 SFM on a buffer, so I’ll want 8″ buffs and a fair amount of speed. The shaft has to be thick because buffers need long shafts, and long thin shafts wobble. With a long shaft, you have access to deeper areas on parts, and you can also mount sanding drums on the buffer.

Should be pretty cool. If I go through with it.

I also learned that you can use a 2×72 belt grinder to drive a buffing attachment. You buy a 2×72″ drive belt (not abrasive), and you make a buffing attachment that fits on the end of a tool arm. The belt drives the attachment. You can use it for anything that will work on a small arbor. It’s brilliant. Some day I want to try it. Depending on the VFD and the size of the pulley on the attachment, you can get a crazy-wide range of speeds.

Last thing: I’m turning a chunk of mystery steel into a bench block. I found it in an abandoned warehouse. It’s about 3″ x 2″ x 4″. I tried to fly-cut one side, and I learned this: fly-cutting is not for steel. With a 3″ fly cutter and an HSS bit, you have to do something like 90 RPM, and that takes forever. I burned up my cutting bit several times. With aluminum, you can run flat-out, but steel is not as friendly.

I suppose I could put a quality left-hand lathe tool in the cutter with a carbide insert, but for the moment, I’m going with an indexable 2″ end mill from Shars. I happen to have a box of TPMR inserts I bought by accident (no screw holes), and they will work with this end mill. It should be a lot better for steel, although the finish may not be fantastic.

A bench block is like a miniature anvil. You put it on your workbench and rest things on it while you work. You can put a groove in it to hold long things horizontally, and you can put vertical holes in it so you can drill things on the bench and go all the way through them. It’s a nifty item to have, and making it is good machining practice.

That’s about all I have at the moment. I may post photos later when I have more time.

More: Eastwood Rocks

The cart I bought from Eastwood had a minor defect, as I mentioned above. I got on the phone with them and told them about it. The cart has four tubular supports that hold the top shelf. Two are big tubes which are part of the cart’s frame. The other two are smaller tubes, maybe 5/8″ in diameter. On my cart, one of these tubes has crooked threads in the end, and it’s about 1/4″ too short. I had to shim it with washers to make it work.

Guess what Eastwood’s solution is? They’re sending me a new cart. They can’t pull the part and send it, and they don’t want the old cart back. Translation: free cart. I can fix the old one. It already works with the washer shims, but I can weld two ends in a piece of steel conduit and thread them, and it will be a perfect replacement for the defective support. I can even paint them black so the part looks OEM.

This is sweet. I don’t need two welding carts, but the cart doesn’t know it’s a welding cart. I can put my bench grinder on it, and I can put a buffer on the bottom shelf. I can put up to 350 pounds of stuff on it. I can even store extra gas bottles on it, if I choose to get into TIG or something that requires gases other than Argon/CO2.

Eastwood is kind of a neat company. They specialize in finding low-cost stuff that works reasonably well, and they are very aggressive about courting customers and making them happy. They’ve put a lot of self-help videos on Youtube.

I have a free 2HP motor, a free treadmill motor, a free linear actuator, and a free welding cart. What else do people want to give me?