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Archive for the ‘Tools’ Category

CNC Surprises

Thursday, September 18th, 2014

No Cigar

I feel like updating the saga of my CNC progress. I have learned a great deal about CNC, but in relation to the amount that I need to know in order to be competent, I know just about nothing.

First thing: do not build a CNC lathe. Do not even waste your time. A mill will do nearly everything a lathe will do, plus a million things a lathe can’t begin to do. You can thread with a mill. You can turn parts with a mill. You don’t want a lathe. Believe me. And if you have a lathe, no one will want to help you, because only about 10% of CNC hobbyists use lathes. Even software makers ignore us.

Second thing: precision is expensive. You can fix a machine so the computer compensates for backlash. But it doesn’t actually work. Say you’re milling a round hole instead of boring. You have to make the cutter travel in a big circle, as well as rotating. Every time an axis changes direction, you’re going to get error due to backlash. The only way to get rid of it is to use ballscrews, and cheap ballscrews don’t really work, although they may make you feel good. On the web, people with cheap screws talk about backlash figures between 0.005″ and 0.010″, which is huge.

When I got ready to build my lathe, I figured the machinery itself would be simple to create. The plans I bought didn’t mention ballscrews. Then I got it running and found out I had 0.018″ of backlash on the z screw. The software compensates on simple parts, and that’s very good. It’s worth a lot. I can do a lot of stuff I could not do with a manual mill, and I can do it with good accuracy. But sooner or later I’ll want to cut a part that requires a sudden change in direction on z, and I won’t be able to do it well.

Another annoying lathe issue: you have to tell the computer about the cutters you use. When you use a tool, only a tiny part of it will touch the work. The computer has to know where that contact occurs. Tools have rounded corners, so there won’t be a sharp, defined point where the tool makes contact. It will vary as the shape of the work and the direction of tool movement change. Lathe inserts vary a lot, so you may have to have a whole bunch of tools defined. I’m not sure HSS is useful at all, because you can’t grind it precisely. If you try to tell the computer the radius on a tool made from HSS, you’ll definitely have error.

I have not used a CNC mill, but it stands to reason that it should be less complicated. Say you’re using a half-inch end mill. You know exactly where the lower surface is, at all times. You know where the sides are. Not complicated. Maybe I’m wrong, but I can’t really see myself spending days telling the computer about the small number of tools I’ll use.

I’m going to keep the lathe, because even with limited precision, it can be useful, but I would not waste my time building another one. I’m hoping to use it for threading and tapers, as well as curved parts like dial handles. Things like that will justify its existence until I get a mill going.

People are telling me I should have bought a used machine. There are a lot of old CNC machines out there that have obsolete electronics. I may be wrong about this, but I will relate what I understand to be true. Years ago, CNC required big dedicated computers and expensive controllers. In 2014, a secondhand PC can handle most of that stuff. There are old machines out there with screws and motors that still work, but they have heavy, useless built-in electronics. Commercial users want to get rid of them, so hobbyists buy them and bypass the ancient circuitry, running them with Mach3 or LinuxCNC.

I would love to have an old vertical machining center, which is just a very fancy milling machine with an enclosure that keeps chips and coolant contained. But they’re gigantic. There’s one for sale down here, and it weighs over 8000 pounds. I’m crazy, but not that crazy. Also, what if you buy one, and the screws are no good? You’re out maybe six grand, and then you have to put another two or three thousand in. Arrgh.

I am thinking I should get a new Chinese mill, like an R45 clone or a Grizzly G0704, which is a little smaller and less rigid. I would have to put decent screws on it, which would give me gastric distress, but it would do just about anything I want to do. I still have the ability to add 6 more axes to my controller, so I should be able to keep the lathe and add a mill with no problems.

I bought Dolphin CAD and CAM, which is a pretty good commercial program. They gave me a big discount. I haven’t gotten to where I can actually use it, but I’m working steadily. I have managed to get Mach3 working (most of the time), so I use it to fine-tune the machine. Yesterday I cut a #2 Morse taper in aluminum, just to see if it would work. Tapers have to be very precise, but the geometry is simple, and the tool doesn’t change directions while it’s on the work, so I figured there was some hope that my lathe would pull it off.

Below is a photo of the taper. It fits fine in the center bore of my rotary table. I put Sharpie ink on it and tried to rub it off on the inside of the bore, to check for high and low spots, but I couldn’t see any problems in the result. It would definitely be sticky enough to hold a drill chuck in the lathe’s tailstock.

09 17 14 Morse 2 taper cut on mini-lathe

If I can make tapers that actually work, it will be a nice ability to have. I should cut an R8 and see what happens. My experience with lathes is that even with error in the chuck, you can get a very nice, round part as long as you don’t move it around while cutting it. If you take it out and put it back in, it won’t be in the same position. I don’t think it’s unrealistic to try to make an R8 taper, but the dial indicator or test indicator will tell me for sure.

I am enjoying the lathe. I plan to keep working on it until it can thread. But compared to a mill, it’s…handicapped. That’s just how it is.

The Unlikely Smell of Success

Sunday, August 3rd, 2014

Lathe Debut Imminent

I’m not at church today because the A/C blew out. I can’t wait until we have our own building.

The CNC mini-lathe is pretty much done. I have to get the electronics going, but apart from adjustments and nonessentials, the hardware is ready to go.

I will not criticize this design, because I am not competent to do so, but I have had some negative comments from experienced CNCers. They don’t like the direct couplings between the steppers and screws, and one said it was a bad idea to use a lead screw to move the saddle. I don’t know what else you would use, though.

Yesterday I cut the lead screw to size. It had to be 22″ long, with a 1.75″ portion turned down to 0.25″ to receive an adjustable collar. I got it to about 0.248″.

Turning a lead screw in a lathe is pretty nerve-wracking. If you simply stick it in the chuck, you risk ruining the threads. You can bore soft jaws out so they hold it without marring, or you can make a split bushing that goes over it. You chuck the bushing, and it tightens around the screw without harming it.

I made bushings, but in practice, they were no good. When I chucked the screw, it wobbled pretty badly. I considered boring my soft jaws, but I wasn’t sure I wanted to bore all the way through a brand new pair. I might need that metal for something else later.

This was not a precision job, and I had extra screw material, so I tried the gonzo approach. I wrapped the screw in several layers of foil and chucked it.

It’s hard to put an indicator on a coarse thread. It will bounce around. I decided to eyeball it. I put something straight next to it and turned it, and I saw no deflection. I knew that put me within a couple of thousandths, which is not far from the best the chuck can do, so I was happy.

I center-drilled the far end, put a live center in it, and turned 1.75″ down to size. No problems. If it’s not perfect, I can’t detect it without instruments, and that’s more than good enough.

08 02 14 CNC lead screw turned to size

I had a problem when I mounted it on the lathe. I have some new flexible “plum” couplings, and I put one on the z screw. These couplings have an aluminum spider fitting at each end, and in between, there’s a layer of urethane, like a skateboard wheel. They allow for a lot of error in the rotation of the things they connect, but they also pull apart if you pull the ends away from each other. I want my setup to be rigid longitudinally, so the screw isn’t slopping back and forth and creating incredible backlash. I had to go back and use my old rigid connector, which works fine.

Plum couplings are perfect for the x axis, except that the one I got was a tiny bit too long. There was a layer of urethane between the shafts I was connecting, and it was too thick. In order to use it, I would have to make a thicker x mount or alter the coupling. I’ve made the x mount twice already, so my answer was to mill the urethane out. It should not matter. It installed easily, and it looks like it will run fine.

08 03 14 CNC lathe x axis mount with plum coupling

The z screw system goes motor, coupling, screw end, adjustable collar, wave (spring) washer, thrust bearing, mount, thrust bearing, screw body. The collar appears to be there to hold the screw tightly against the mount, putting pressure on the washer and bearings. It has to be very tight. I had problems with it slipping. I had to tighten it to the point where I was afraid the set screw would strip. I don’t know if 0.248″ is too small for the collar or what. When I made the screw, I assumed a couple of thousandths wouldn’t matter. It’s adjustable, right? But it may be that I need to put some foil inside it to take up room. Or maybe I need to make a bigger, tougher collar. In the real world, there would be a taper, I guess, with the bearing pressed onto it so it could not move. But this is not the real world. This is home CNC.

08 03 14 CNC lathe z axis mount with coupling and bearings

I don’t have a project box, but I have a Bud Portacab on the way. This is a foot-tall lunchbox sort of thing made from aluminum. I want to put plugs on the back for 8 motors (the limit for two Kstep boards). I’m not sure what kind of connectors to use. They have to be 4-wire connectors that will handle up to 18 gauge wire. I will also need a plug for the lathe’s spindle sensor.

I’m getting a lot better at machining, because I have no choice. It’s easy to machine when the plans are in your head, and everything is approximate. When you’re working from drawings, you have to apply yourself.

I’m hoping to see movement from the lathe this week. I need to get it put together and figure Gcode out well enough to do a simple cut. After that, things should get a lot easier. It will just be a matter of study and practice.

Most CNCers don’t do lathes, and that’s understandable. A mill will do a lot more. But I don’t have a mill waiting to be hacked up, and the mini-lathe was sitting here doing nothing. It should be very useful, though, and it will give me some understanding of the most important tool technology of our age. Most people are getting left behind when it comes to CNC/3D printing, and ten years from now, they’ll be like the old geezers who hate cell phones. “Damn this thing. Hello? Hello? What? I have to open it? Hello? Hello? Which button?”

After this, I have to make the lathe ball-cutter for which I bought plans. After that, I might like to make a small surface grinder. I considered making a tool grinder, but they’re not really that useful. People tell me that even if you have a great commercial grinder, you will probably do bad work, because it takes skill. And cutters aren’t that expensive, really. A surface grinder would be nice. If you like making machining accessories, you will want truly flat surfaces once in a while, and hand scraping is a real chore.

Hope I have a victory Youtube to post soon.

Nuts to Me

Friday, July 25th, 2014

The 4-Jaw has Landed

I have another machining update. I sometimes wonder if I should put so much of this material up, since some people come here for spiritual stuff. But on his own blog, a blogger is a dictator who answers to no one, so here I go.

My first rotary table was a 10″ Phase II. I wanted something big so I would not run into the tool-user’s curse, which is needing a bigger tool ten seconds after you unwrap the one you just bought. Phase II tables are made to mate with 3-jaw chucks one size smaller, so I put an 8″ chuck on this table. Together, these items weighed so much I could not lift them well enough to move them. At least I don’t think so, because lifting the table all by itself is risky. I don’t think I’ve ever lifted them when they were joined.

Eventually, I decided I had had enough of moving this thing, and I decided to get a 6″ table. Unfortunately, Enco had a great price on 8″ tables, so that’s what I bought. And I bought a 6″ chuck for it, because mating an 8″ 3-jaw chuck to it is virtually impossible.

Had I bought a 6″ table, moving the table and chuck together would not be all that bad, but with the 8″ job, I have to separate them.

Generally, my solution to this problem is to leave the table on the mill all the time. I have not yet had a job big enough to make it necessary to remove the table. The 10″ table was a little annoying, but the 8″ one is reasonably unobtrusive when I’m using the vise.

I can tell you find this post exciting.

One of the aggravating things about having a 3-jaw chuck on a rotary table is that every time you remove the chuck (which is necessary in order to clamp stuff to the table), you have to use a dial indicator on it when you put it back on, to make sure it’s centered on the table. A while back, I got the bright idea of using a 4-jaw table instead. It would be 2″ bigger, because 4-jaw chucks are less annoying to mount, and I would not have to indicate it.

I totally forgot that I would have to indicate EVERY SINGLE PART I put on it. But that’s okay. It can do everything a 3-jaw can do, it holds bigger work, and it allows you to machine irregular parts. You can also machine stuff that isn’t centered, and you can use the chuck as a faceplate if you remove the jaws.


I ordered an 8″ Phase II chuck. It looks fine, but it came with a lot of grit in it, and the machining in the jaws and slots is somewhat crude.

When I asked Phase II if there was an adapter plate for mounting it, they told me there was not. I thought I would have to make one. But the chuck has 4 holes for mounting cap screws, and there are 4 T-nut slots in the table. Measuring carefully, I realized that the slots were juuuuust deep enough to permit mounting the chuck on T-nuts. Problem: the nuts I had are rectangular, and the slots are semicircular at the extreme ends, so the corners on the nuts prevent them from going all the way in. I had to machine the corners off or make new nuts.

I suspected the nuts were hardened, and they were too small to machine easily, so I got out a 3/4″ by 1/2″ bare of 1018 steel and made new nuts. Here is a shot of part of the process. It got prettier later on, but this is my first effort.

07 11 14 making rounded t nuts for 4 jaw chuck on mill

That thing in the collet is a stud. I used it to center the screw holes under the spindle. Later I made a tool from 1/2″ aluminum rod. The end was turned to an unthreaded diameter that fit snugly in the tapped holes. I put the tool in the collet, used it to center the work, clamped everything, and replaced the tool with a 1/2″ cutter.

The job was simple. First I made a long bar of steel with the same cross-sectional profile as a nut. It was 0.700″ wide at the bottom, and it had two shoulders cut into it so it was 0.450″ wide at the top (the name “T-nut” comes from this shape, which is an upside-down “T”).

Then I drilled and tapped several M10 x 1.5 holes through the bar, for the cap screws.

After that, I clamped the bar to the rotary table and machined two radii into the end. I used the band saw to cut the bar into individual nuts. It was a fairly pretty operation. I had to do some filing to get the last few thousandths of necessary clearance, but now I have this:

07 23 14 4 jaw lathe chuck mounted on 8 inch rotab with special nut

You can see one of my round nuts on the table. That’s a crude one I made as an afterthought. It doesn’t have a pretty round end on it like the others.

Under that table, there are two nuts with one hole each and two nuts that have two holes each. I was going to cut them down, but I thought maybe I would get some type of versatility if I had different types of nuts, and it saved me some work, which was probably my primary motivation.

My next project is to make special T-nuts that fit the jaw slots. I have been told this will damage the slots, but I think that’s wrong. I can make them from brass or aluminum, so they’ll be softer than the table, and I can make them long, so the pressure is distributed over a wide area. I got this idea from my 10″ 4-jaw (on the big lathe), which already has faceplate slots cut in it. Granted, these slots are separate from the jaw slots, but I still think my idea will work. It would make it totally unnecessary to remove the chuck when clamping things. If I don’t like the way it works out, I can always make a round, thick aluminum plate, attach it to the chuck through the existing screw holes, and mill or fly-cut it so it’s level. I can mark it so it’s always mounted the same way, and that should give me reliable flatness every time I bolt it on.

Now that this is behind me, I can move on to the assembly of my CNC lathe’s control box (probably the wrong term for it). It will house the power supply, controller and drive board(s).

Stuff is getting done. The backlog is dwindling. Praise the Lord.

CNC Lathe Motors Mounted

Thursday, July 24th, 2014

Send Out the Dancing Girls

Should have appended this to my last post.

Yesterday I stuck the motors on my CNC lathe. The plans called for 10-32 screws, which seems like a bad idea on a metric lathe. I followed the plans, and I ended up with threaded holes bigger than the holes on the motors. In order to pass a 10-32 screw without a lot of slop, you need a hole drilled by a #10 bit, pretty much. That’s the size I chose. I put the motors on the mill with a stop in the vise, and I lined the holes up with the drill chuck as well as possible, and I opened the holes up using my one of my lovely new Harbor Freight HSS drill bits.

The motors screwed right onto the mounts. No problems. Like they grew there.

07 23 14 stepper screwed to x mount with knob mockup

The lathe is virtually done. I have to put a lead screw on it, which is a nothing job, and I also have to install a sensor and two couplers. The knurled knobs need to be opened up a little, and I need to put set screws in them, but that’s very easy.

I did a fine job modifying the lathe, and I even improved a couple of things. Now I’m just waiting for a few parts, including the power supply. I think I’ll start my Meshcam trial on Monday.

If I were starting fresh, I’d use metric stuff for as many items as possible, but it won’t matter.

I am wondering what else can be done with a lathe. What if I had a milling attachment? That could be used for things like broaching. What if I CNC’d the spindle motor? It seems to me that a lathe could do a lot of milly things if it were set up right. I just have to go slow and see what works.

“Please do not Power off or Unplug Your Machine”

Thursday, July 24th, 2014

“Use a Shotgun Instead”

People are commenting on my recent PC upgrade ordeal. There is more to the story.

Yesterday I put the PC back together and got ready to enjoy it. Then UPS delivered the new video card, so I had to take the box apart all over again.

I put a 27″ TV in the garage because my monitor made my eyes hurt, and I wanted to use the HDMI input instead of the VGA input, figuring it might work better. I ordered some sort of Geforce card which would work with my PC. A cheap refurb from Newegg.

When I turned the machine off to open it up, Windows told me I had 15 updates to install. No warning. Just, “Sit down and wait for an indeterminate period.” And of course, some updates installed in a few seconds, and others took forever.

Then the machine started turning on and off. My favorite part was when it said “Configuring Windows – 32% Complete,” then “Welcome,” then “Shutting down.”

I got the silly thing installed, and then when I turned the PC on, I had 800 by 600 resolution, which is pretty awful. Windows 7 didn’t have the right driver. Of course. So I went to the Geforce/Invidia/whatever site to start on the three-minute job of downloading the correct one.

The driver package–I am completely serious–was 221 MB. And the server was not setting speed records. The little speed indication kept changing: “14 minutes remaining'; “11 minutes remaining”; “28 minutes remaining.”

Then I clicked on the download, and while it tried to install, it showed me ads for Nvidia products. Talk about bad timing.

Then the installation failed.

I tried again, eliminating all the choices which seemed irrelevant, and the driver installed.

I could not believe it.

I learned a few things about “new” (probably 2009) video cards. This one does audio as well as video, through one HDMI cable. That’s nice. I was able to disconnect the Y-cable I bought for the audio about three days ago.

I got the thing running, and before I was even done feeling sorry for myself, I found myself in heaven. Good things I had not anticipated were happening.

The wireless mouse and desktop worked over a longer distance than I had realized, so I was able to sit on the garage floor in a backpack chair and run the PC. That was great. And I was able to run Youtube videos in full-screen mode. Bliss. I fired up a series of Tubalcain machining videos and felt the upgrade welts fading.

Here’s a photo:

07 23 14 garage PC with Tubalcain shaper video

Videos are getting so good now, watching Youtube on a large screen is actually a pleasure.

I am still working on quenching the intense malice I feel toward Bill Gates and everyone who has a pocket protector. But other than that, this turned out pretty sweet.

Kill Bill Pt. III

Tuesday, July 22nd, 2014

Gates Must Pay

Over the last few days I upgraded my garage PC to Windows 7, so naturally, in spite of my near-total holiness and renewed character, I am having homicidal thoughts about Bill Gates.

The XP “crisis” was announced a few months back, and I got all excited and bought two copies of Windows 7. Then the drop-dead date passed, and nothing happened, so I procrastinated. I started thinking maybe Microsoft would wise up, in the hope of avoiding massive lawsuits, and continue providing limited support. They seem to be doing that, because I never stopped getting updates.

Anyway, with the CNC lathe nearly finished, I figured it was time to do something. I don’t want to set a PC up for CNC and THEN upgrade.

Elsewhere, I described my experience thusly: “Upgrading my computer’s OS was like being dragged naked over broken glass in hell behind a flatulent donkey with a boombox on its back playing ‘La Macarena,’ which is to say, relatively painless compared to previous upgrades.”

I guess that’s accurate. It was horrible, but survivable.

Microsoft–this will shock people–really screwed up the entire process. I can provide details to help other people who are stupid enough to upgrade.

First, you need the upgrade compatibility tool from Microsoft. It’s free. You run it, and it examines your PC carefully, sends all your personal data to the NSA, and then fails to tell you about all the things that will go wrong when you upgrade. It pretends to tell you, but it misses things. Run it anyway so you can tell people to shut up when your upgrade fails and they start yammering about the compatibility tool.

Second, you need to find out whether your existing programs, for which you probably paid several thousand dollars (unless you’re a typical software thief), will run under Windows 7. If you don’t have time to do this, I’ll help you: they won’t. It’s just way too hard for a hundred thousand overpaid software engineers to make advanced software that is capable of running more-primitive programs. And if it happens to make Bill Gates more money, by forcing people to buy new versions of Office, well, that’s just a coincidence.

I upgraded my ancient PC, and it ran fine, and then Windows 7 told me it wanted nothing to do with my ethernet card. So I had a problem that could best be fixed using the Internet, and the one thing it prevented me from using was…the Internet.

This PC was free, and the motherboard’s LAN port blew out early in its career, so there was a Netgear card in there. And Netgear had a patch to make it run with Windows 7. Laboriously, I moved the patch from another PC to this PC, and it did absolutely nothing but get my hopes up and waste my time.

By the grace of God, and for no reason I can now guess, I had a totally unneeded LAN card in my main PC, so I stole it, put it in the garage PC, and succeeded in getting connected.

Then the PC started quitting and refusing to start.

This is how computers are. A computer never has one problem. It always has a bunch of problems, all at once, that are unrelated, yet which work in synergy to destroy your will to live.

I went all through the stupid thing. I put in a day of work. I checked connections. I messed with the “on” switch. I got it going. Everything was fine. I left the room. I came back. The computer was off.

Eventually it occurred to me that the power supply might be hinky. In order to test it, I took it out, removed the cover, and electrocuted myself. That was actually unintentional and provided little useful data, but I did do it.

Today I drove to Tiger Direct and got a new power supply. I plugged it in, and the PC went insane, because I had moved some jumper or other. When I finally got it going, it told me it had 168 crucial Windows updates to apply. That was like an hour ago, and I think it has installed 3.

Windows 7 is actually pretty good. When I say that, I feel like a cancer survivor saying dysentery is pretty good. But it’s really not bad. I had always thought that 7 was Vista, which is three levels worse than cancer, but it turns out it’s just XP with fewer landmines.

I still haven’t installed my more-expensive Windows programs. I am positive Finale won’t work, based on the fact that I really like it and want it to work.

Windows 7 has a fairly stupid way of making SOME random programs (i.e. not the ones you care about) work. They don’t tell you this when you install it. You have to download and install a continent-sized program called XP Mode. Then XP Mode disappears, and you can’t run it. That’s because you didn’t install Virtual PC, which Windows didn’t tell you about, when you installed XP Mode. So now you have to install Virtual PC, which takes another year and a half.

When you get all that done, you MAY be allowed to install your old program, in a fake XP window.

Or not. And if the answer is “not,” and you have to buy more programs, giving other billionaires just like Bill Gates even more of your money, well, that’s just a coincidence.

Now my PC is lying on its side with the updates running (or not), and I can’t put it back together until it gives me the go-ahead.

If you try this yourself, may God be with you, because Microsoft definitely will not.

CNC Lathe: Electronics on the Way

Friday, July 18th, 2014

Progress Report From the Crazy Neighbor Who Never Leaves the Garage

The CNC project is moving along well.

Because the machined parts for adapting the lathe are mostly done, I’m thinking about electronics and software. I will write what I’ve learned and concluded. Some of it is surely wrong, but for someone else in my position, coming along later, it will be a lot better than nothing.

First of all, if you’re doing CNC, you should join the Home Shop Machinist board. There are other forums that are useful, but if you’re starting at the bottom, they are likely to ignore you. I have a CNC Zone account, and it’s nearly useless. HSM is friendlier.

Here is my understanding of the way a home-grade CNC machine works. You need 1) a PC, 2) an external controller, 3) a board that drives stepper motors, and 4) stepper motors.

Some people do not use external controllers. Based on what I’ve read, I think that approach is only worth discussing if you want to dedicate an entire PC to nothing–and I mean nothing–but controlling a machine. If you use your PC for music or the web while you work, it will interfere with the CNC machine, and you’ll hate life. So I am ignoring this option, and I know little about it.

The external controller takes output from the PC and turns it into signals that the stepper motors like, if I understand it correctly. Then the drive board turns these little signals into big ones that go right into the motors and make them run. Your PC’s ports can’t do that. The motors need too much juice.

To make the controller and drive run, you’ll need a power supply for them. Actually, I believe you’ll need more than one, because one powers the motors, and the other will power the computerized stuff in the boards. The voltages for this stuff–which nerds refer to as “logic”–are lower than the voltages for the drive.

If you can’t stand the thought of having your machine close to the PC, you will want an ethernet-based system. It will let you have long runs with ethernet cable. Otherwise, you’re stuck with USB. I’ve heard limiting distances described as 5 feet, and I’ve also heard 16 feet. I don’t know which is correct. I would assume that the limiting distance is between the PC and the box with the controller and drive, since the wires that go to the steppers are ordinary 4-conductor jobs with a decent amount of current flowing through them.

If you want ethernet, you will have to use a Smoothstepper drive. Sadly, it only works with Mach3 software, so if you hate Mach3 (many people do), you will be SOL. For this reason, I chose USB.

The USB solution I chose was a Dynomotion rig. They make the Kflop controller and the Kstep drive. These boards are made for each other, and they can be connected with one ribbon cable. They are sized so you can mount one on top of the other. You can run 4 motors from one Kstep, and you can screw another Kstep on top of it for four more motors. You can use other drives, but they aren’t going to be plug-and-play with the Kflop.

With Dynomotion, you don’t have to use Mach3. I guess I should say what Mach3 is.

To design a part, you may want to use CAD software, although you don’t have to. It will allow you to draw the part, with all the measurements. Then you feed this to CAM software, which turns it into something stepper controllers can eat. That something is called “G-Code.” It’s a language, like Pascal or Basic. I don’t really know how this works, but I think it will show you the path the tool will take during the operation you’re planning, and you can check it over and see if it makes sense. There are also G-Code editing programs, which are sort of like Turbo Pascal. They’re word processors for G-Code, and I believe they also compile it. Compilation is the process of turning written code into programs.

If you are a true uber-geek, you can bypass a lot of this stuff and just write the G-Code, but I think you have to give up diurnal life and sleep in a closet, hanging upside-down. I don’t think normal human beings can do it.

CAM (Computer-Aided Manufacturing) software is hideously expensive, with $1500 programs considered cheap, but there are free options, and there is a $250 program called Meshcam which is popular with unsophisticated users. They have a 15-day trial, which I plan to sign up for after the machine is running.

Mach3 comes after the CAM software, and it talks to the controller. Mach3 is user-friendly, and it has tons of users who have built up a big knowledge base, but many people complain that it’s buggy and ruins a lot of parts. Sometimes CNC doesn’t work, and when that happens, you throw out expensive metal, and you may have to jump to prevent a machine crash. The negative things I’ve read about Mach3 convince me that I should try to avoid using it.

Dynomotion makes a free product to get people free from Mach3. It’s called KMotionCNC. I am hoping I can make it work.

I know zippity-doo-dah about computer programming, having taken precisely one course over twenty years ago, but I believe G-Code is based on C, because CNC people keep saying “C” when they discuss it. In any case, you have to be able to do a certain amount of programming in order to survive, because none of this stuff is really ironed out well enough to trust.

I downloaded a free G-Code editor called RapR3D. I don’t know if it’s any good, but I’m sure it will suffice to get the basics into my head, and that’s all I’m after at the moment.

I have a Kflop, Kstep, and power supply on the way.

Power supplies are extremely confusing. The motors are generally rated for between 2 and 5 amps per phase, and the voltage ratings are below 10, but you are expected to use power supplies with output voltages up to 25 times as high as the motors’ rated voltages. This is normal. The motor specs will not tell you how high to go. I ordered motors that go around 3 amps, and I have chosen a 48V power supply. I know it will work. Other people have used it. You want a lot of voltage. It makes the motors jump around better.

How do you determine the amount of current you need? You multiply the current rating by the number of motors, right? Right. If you listen to people who don’t know anything. In fact, you don’t need to go higher than 2/3 of this number. People will argue about this, but they’re wrong. The motors will draw less than the rated amount of current, because you will be “microstepping.” That means that instead of going a full step with every pulse of juice (1.8 degrees), you will move through a smaller angle, or “microstep.” The motor will produce less than the rated torque, but that’s okay, because you don’t need the rated torque. If everyone else is using 300 oz-in motors for your application, you can use them, too. You don’t need to know exactly how much torque you’re getting. Does the machine run? If so, you have enough torque.

I would like to have a second machine on my system, and that would be a mill. It could have as many as 4 motors, making a total of 7, including the lathe. I can do that if I get a second Kstep board. But I’ll need current for 4 big motors, not 2 medium-sized ones. The big motors are rated at 5 amps. That means I’ll need 13.33A, or 2/3 of 20A. There is a well-known guy called “Hoss,” and he built a Grizzly G0704 CNC mill. People told him he needed a huge power supply, but he put out a video running three axes simultaneously with a small one, and he never hit 4 amps. He says he would be happy to use a 12.5A supply for five axes. I believe him. He certainly knows more than I do. I ordered a 16.7A supply.

I don’t know why the current draw is so low. Maybe it’s the microstepping, or maybe the current comes in little pulses with breaks between them. Maybe it’s because the voltage is so high, you need less current. But I’m confident that the 2/3 figure is correct. The people at Gecko drives agree.

There are two types of supplies. Regulated (“switched” or “switching”), and linear (“unregulated”). The regulated ones have voltage regulators, and they’re made with flimsier components. Unregulated supplies are supposed to be sturdier, and they have various other advantages which I can’t remember right now. I do know this: switching supplies require fans, and if the fans fail, they fry. Dust–not a rarity in garages–kills fans.

Hoss uses a cheap switching supply in his video, but for me the price difference between regulated and unregulated was about ten bucks, so I went with unregulated. Delivered, it will be $141.00. Was it a waste of money? Probably, but ignorance is expensive, and at this stage, I am ignorant. I want to be safe. I would rather buy one pricey supply than a cheap one that blows up, followed by a pricey one.

I’m going to need a box. I’ll mount the Kflop/Kstep combo in there, along with the power supply. I will need a repurposed wall wart to power the logic circuitry. Wall warts can’t really be hardwired, so I suppose I’ll stick a cheap power strip inside the box and plug the wart and PS into it. That’s easier than trying to cut up a plastic wall wart case.

If things work out, it will go like this: PC >> USB port >> Kflop >> Kstep >> steppers >> cool parts >> joy.

This is not a simple project. The user end of the technology is extremely primitive right now. I told someone my dream was to describe parts orally into my cell phone while driving home, and then to find them finished when I arrived. I was kidding, but anyway, it’s nothing like that. You have to know a fair amount about electronics. You have to learn some programming. You have to be able to debug things you know little about. On top of that, before you begin, you have to be a machinist. But the reward, even at this late date, is that you’ll be a decade ahead of everyone else. I seriously doubt that even 3D printers and routers, which are pretty simple compared to other applications, will be in most home workshops within five years.

It’s turning out to be expensive. I’m sure it will be over a thousand dollars, not including the lathe and tooling. And when it’s over, I’ll have a lathe, which is possibly the least-exciting CNC tool. It’s so unexciting, the vast majority of CNC hobbyists are doing something else. It should be very useful, though. Once you buy a lathe, it takes about thirty seconds to run up against a job you absolutely cannot do without CNC, a tracer, or gears you don’t have.

One nice thing about this is that the first tool is the biggest hump. If I add a mill, I won’t have to buy new software or a new controller. I’ll just need the drive board, a machine, and the steppers.

CNC mills are incredibly cool. Go to Youtube and see. You can make stuff you would not believe.

Someone told me I should have CNC’d the big lathe, because the cost would be similar, and I’d be able to do more stuff. I’m not ready to screw up an investment that big, but it may happen later.

This is where I am today. There are probably about 300 errors in what I wrote, but I’m going forward anyway, because you can’t solve all your problems by theorizing. Eventually you have to have a project sitting in front of you.

My guess is that I’ll be able to make a part by August 17, one month from today. I think that’s a very reasonable goal. I am hoping I’ll be good enough to get practical use from the machine a month after that.

It’s very exciting. I will keep you informed as I go.

Doofus-Proof Drawbar Whacker

Tuesday, July 15th, 2014

You Need It

Here is an update on my machining.

I have the parts for my CNC lathe conversion mostly done, and I’m going nuts trying to pick motors, controllers, and so on. I have nothing coherent to say about that. But I do have something helpful for people who–and I know nobody who reads this blog would do this–are absent-minded enough to leave a box wrench on the nut of a milling machine drawbar. The big problem with this is that if you turn the mill on, the wrench spins with the nut, and depending on which way it goes, it will either loosen the drawbar or snap the shear pins inside it. Or, if you have a crappy drawbar with no shear pins, it will spin the drawbar in your taper and mess it up.

I know someone who has a Grizzly mill with a solid drawbar, and he now has grooves inside the taper. Some imbecile left a wrench on my mill’s drawbar (no need to reveal his identity), and when he snapped the pins, all he had to do was order an $18 replacement off Ebay. And he was able to cram a new pin in the old one to make it work until the new one arrived.

For God’s sake, go check your drawbar right now. If it doesn’t have shear pins, get a new one. They’re cheap. If it has pins, you will see their ends through the finish close to the point where the thin part goes into the fat part.

Anyway, a drawbar wrench should be able to perform two purposes: it should tighten and loosen the drawbar nut, and it should also be heavy enough to whack it to make collets and stuff drop out of the taper. I came up with a tool that will do those things AND which can’t be left connected to the drawbar.

I made a cylinder of aluminum with a hex protrusion on one side, to fit snugly in a 3/4″ box wrench. I tapped the hex part for a 1/4″ screw. Then I stuffed the hex into a wrench, added a screw and washers, and I was done. Here are two photos of it being made.

07 15 14 drawbar hammer on rotary table

07 15 14 drawbar hammer assembled on bench

If you’re a machinist, you will appreciate this. Last week I wised up and got a 4-jaw chuck for that rotary table, because a 3-jaw is a really stupid choice. I found I had to make special nuts to hold the 4-jaw on the table, and I have not finished that job. I haven’t really needed the 3-jaw and table for a while, so I had no issues with removing the table to use it to make the nuts. That was like 3 days ago. And today, naturally, I needed the 3-jaw for this job. So I had to put it on the table and indicate it. Isn’t this always how it goes? The minute you break something down, you need it.

Most people use brass for drawbar whackers, but it doesn’t matter. Aluminum works fine.

I haven’t Loctited this thing, because I want to add better washers. I considered machining one, but I really don’t feel like struggling to machine thin work today.

Tubalcain, the machining star of Youtube, has a similar project, but mine is way cooler. He didn’t pretty his up. Mine is chamfered, and the exposed sides were turned on the lathe. His left baby toe knows more about machining than I do, so I feel smug about doing one thing better than he did.

I hate to doink this thing up by using it.

The wrench is a Husky from Home Depot. You may think it’s not important to mention that, but it is. It’s surprisingly hard to find a long 3/4″ open wrench that isn’t offset.

Machining Progress for June

Saturday, June 21st, 2014

This Junk Actually Works

I guess people who come here solely to read about God will be sore, but I am here today to talk about machining. I am making progress on the parts for my CNC mini-lathe. You can find and buy the plans at Ron Steele’s site.

In an earlier post, I discussed a mount I was making from aluminum on the mill. If you look at the photo, you can pretty well tell I was milling it from flat aluminum plate. I had a few problems. First I misread the plans and tried to make it from 1/2″ plate. Then I saw that it was supposed to be 3/4″ thick. I started over.

The plans called for a 0.510″ bore down the center of the part, to accommodate the screw that moves the lathe cross-slide. The bore had a shallow 0.625″ counterbore, because the screw has a shoulder on it, and the shoulder fits the counterbore. On either side of the bore, centered 0.411″ away, there was a #18 hole drilled through, and there was also a 0.297″ counterbore in the #18 hole locations, to a depth of 1.1″.

This means there was a big bore through the material, and to either side, there was a 1.1″-deep bore centered 0.411″ away.

If you add up the numbers, you find that when it’s all done, there is roughly 0.010″ of material remaining between the main bore and each counterbore. For all intents and purposes, that’s no metal at all. And when I shoved a homemade counterboring tool in there to make the counterbores, the thin aluminum sagged and distorted. I could have bored it out and not worried about it, but it wasn’t workmanlike, even by my standards. I decided to make a third part.

I measured the lathe for myself. The plans are generic, for lathes sold by Harbor Freight, Grizzly, and so on. My lathe is a Big Dog, made by a Chinese company called Real Bull. It’s slightly different. I don’t know how closely the plans fit the other lathes, but they were way off for mine.

I needed a bore about 0.400″ wide down the middle, and the counterbore on it only had to be 0.510″, so that meant I could have about 0.060″ of metal on either side of the bore, not 0.010″. Great news.

I also realized that the 1.1″ counterbores were not needed. The whole point of the wide counterbores was to admit fat M4 screw heads. The idea was to slide the short screws down into the bores and then through the #18 holes and into the lathe. This would have allowed me to keep the OEM 10 mm screws. Obviously (now), longer screws would permit shorter counterbores. So that knocked about 0.090″ off the depth I would have to bore. Great.

Looking at the part, I realized it was symmetrical about the main bore’s axis. That meant a mill was not the ideal tool. It was made for a lathe. So I bought a 2.75″ round rod and used it instead of plate.

I cut it to 2.25″ in diameter. I trimmed one side down to about 1.350″ in diameter. That gave me a part shaped like a hat. Then I had to put a 1.500″-wide bore in the big end, to a depth of 1.400″. My ability to bore a blind, flat-bottomed hole on the lathe let me down, so I did it on the mill’s rotary table and got gorgeous results. Now I had to put flats on it in order to turn it into a flat part.

06 17 14 cnc lathe stepper mount on rotary table

The original part was 0.750″ thick. Measuring my lathe, I realized I could make it thicker on one side. That would allow me to rest more metal against the lathe apron, providing more resistance to flexing.

06 17 14 cnc lathe stepper mount in Alibre for aluminum round rod

I guess this is dull enough already, so I’ll just put up a photo of the part being cut to size.

06 18 14 cnc lathe stepper mount partly milled

There is nothing under the part in that picture. People suggested parallels, but I just clamped it in the vise and indicated it horizontal to within a thousandth. DONE! Then I flipped it and rested the new flat on parallels. The result was perfect.

06 18 14 cnc lathe stepper mount milled not drilled

For reasons I no longer recall, I saved the top counterbore for the mill. Not a great idea, but it worked. I used a CDCO co-ax indicator on the main bore, and I got it to within on 0.0005″ tick. That’s crazy, because it was a drilled hole, and drilled holes are not supposed to be that round, but it did work. I opened up the counterbore using a heavy boring head and a cheap brazed carbide boring bar. Then I put the #18 holes in, using a center drill and my new set of cheap Harbor Freight HSS drill bits.

A word about these bits. You need them. It’s a 115-piece set for about $35. People have complained about the points being off-center, and maybe that’s true. The two bits I’ve used cut true, though, and you should be able to fix the bad ones in your set. But there’s more to it than that.

There will be many times when you’ll want to alter a drill bit. I needed a 0.297″ counterboring tool, and I didn’t have one. An expert told me I didn’t want one, because counterboring tools have little pilot doodads that hang off of them, and they snap easily. He said I needed to grind a 19/64″ drill flat on the end. My main drill set is US-made carbide, and I am not going to grind those bits up, because the discount price is over $200. If you have Harbor Freight bits, who cares? Grind away.

Also, cobalt is not ideal for aluminum. I found this out this week. I was drilling slower than I should have, and the bit grabbed and shattered. I think there were five pieces. HSS is less likely to do that in aluminum.

The part is really beautiful now. Much nicer than the one in the plans. In retrospect, I see that I could have done the whole thing from one piece of metal, but I would have had to put it on the rotary table, and with a 3-jaw chuck or a clamping set, that would have been awkward. Which is why I am planning to get rid of that chuck and get a 4-jaw.

06 19 14 cnc lathe stepper mount with main counterbore and attachment screw holes

My measuring capabilities are getting better, so I am now making parts with very tight tolerances. I realized I had no accurate way of measuring depths, so I decided to get a depth micrometer. The Chinese set from Shars runs over a hundred bucks, but some Ebay guy is selling NOS Scherr-Tumicos for about $62, delivered, and now I have one. It’s beautiful. Unfortunately, to measure different depths, you will have to use internal rods of differing lenghts, and every time you switch, you have to put the mike on a reference surface and calibrate it. If you don’t have a granite surface or something else that has been ground flat, you will have a problem.

Now I have to worry about a coolant system. An Israeli company called Noga makes inexpensive flood systems, but I don’t want one. I think it’s unnecessary. I think I can come up with something that just drips. I have never needed to flood work on the lathe, and in order to do it, I would have to cut up the lathe pan, add a drain, add a pump, add a reservoir, and deal with a gallon or so of dirty coolant. I think I can run a tube under the chip guard and mount something on the cross slide, to follow the part. It can drip WD40 or oil directly on the point of contact. People with mills use a ton of coolant, but I don’t think it’s needed here.

Here is the Alibre drawing I did for the part. For some reason, the screw holes in the bottom of the feet are not visible. Not sure what’s up with that. Some people say you have to create an imaginary plane and drill through it.

Anyway, it’s going well. And I think I’m going to have to have a CNC mill and router in order to feel whole. Not sure about a printer. I think they’re only good for 3D prototypes. I don’t know if that’s worth the money, when you can simply make a part or draw it well. I don’t think the flimsy plastic parts these printers make are very useful yet. Maybe I’m wrong. Sooner or later they’ll print things in metal or something durable, though.

If you have a CNC router, mill, and lathe, you can do a ton of stuff that’s actually useful. In fact, you would probably have to hide it from your neighbors in order to avoid running a free fix-it shop.

I guess I’ll spare everyone the story of how I left a wrench on my drawbar and snapped the shear pins when I turned the mill on, but I will tell you this much: if you have a Bridgeport-type mill, and you obstruct the nut somehow while the motor is running, and it quits working, don’t despair. They’re made to take this. Here are the symptoms that will have you wetting your pants:

1. Cutter continues turning under power.
2. Spindle brake doesn’t work.
3. Drawbar nut turns easily, but drawbar doesn’t tighten or loosen when turned.

Here is what happens. The bar has an upper part, which is hollow, and a lower part, which is just a rod with threads at the bottom. The parts are connected by two perpendicular shear pins which are very soft. When you obstruct the rotation of the nut, these pins may snap. Your mill is not damaged. Just pull the nut part up out of the mill, put a rod down into the top and use it to bonk the top of the bottom half of the drawbar to loosen the collet, and draw the bar out through the spindle opening. Then insert a magnet into the top opening and retrieve the round bushing that came with the drawbar. It will be sitting loose on top of the spindle. You’re done. Now if you want you can hammer new pins into the bar, or you can order one online for about $20, delivered.

Right now my drawbar is held together with a single pin I made from mystery metal. I drilled and punched the remains of the old pins, and I lined the drawbar holes up to hammer new pins in, but after the first one went in, the holes, incredibly, were misaligned, so I gave up on the second pin. I ground off the excess, and I was ready to go. I think things worked out fine, because I don’t know how strong that mystery metal is, and I do NOT want pins that are too strong. Next week the new bar arrives, and I’ll keep this one as a spare.

The accident left a couple of tiny dings in the part, but I’ll get over it.

Sorry I don’t have more photos, but I am not really working hard to document this mess.

I can’t wait to get this thing running, but with all my errors, it could be a while.

I am the Duke of Knurl

Friday, June 6th, 2014

Real Men Have Aluminum Dandruff

I’m having a lot of fun making parts for my CNC mini-lathe.

Earlier in the week, I made part of a motor mount. It will hold a stepper motor which turns the cross-slide feed. Well, it WOULD have held it. But I made a little booboo. The plans called for a part 3/4″ thick, 2.75″ long, and 2.5″ wide, and somehow, I got the idea that I was supposed to make it from 1/2″ aluminum plate. The part is now a paperweight. The way I’m holding it in the vise is wrong, but it worked.

06 05 14 aluminum part for cross slide motor mount before boring

I was very careful when I made this thing. I got it within a thousandth of nominal size, or whatever it’s called. I stepped up my measuring game in order to get there. It’s a PRECISION paperweight.

When I started machining, I watched a lot of videos. I didn’t have machinist buddies who could teach me, and the videos are very informative. In particular, I like the ones from Lex Liberato of Swarf Rat. But they have their flaws. For one thing, most of the guys I watched tended to rely on dial calipers, which are not very accurate.

A dial caliper is an improved (arguably) version of the old vernier calipers we used to use in lab classes. Instead of making your eyes hurt from trying to read tiny vernier scales, they have dials attached to them, and they read in thousandths of an inch (imperial calipers only).

It’s easy to get the idea that this means you can measure something to within a thousandth of an inch of its actual size. That’s wrong.

Back when I taught physics labs at the University of Texas, we were told to tell students to try to estimate down to one-half of the length of the smallest unit an instrument measured. For example, if you had a ruler marked in millimeters, you would try to make a good guess and come up with a measurement accurate to half a millimeter. That won’t work with dial calipers, because their accuracy is actually lower than the smallest unit measured.

Calipers flex a lot, and you can screw up the measurement by applying the wrong amount of pressure. They have little knobs that tighten the jaws against the work, but no one with any skill actually uses the knobs, because they kill accuracy. In reality, you’re supposed to put your finger and thumb on the jaws and push them together. There are a lot of problems with calipers, and a very skilled machinist told me never to use them unless I was satisfied with up to 0.005″ of error.

What you really want are micrometers. Calipers are faster and easier to use, so they’re great for interim measurements when you’re working fast, but when you get close to final dimensions, you want something better. Micrometers will get you within half a thousandth when used badly. If you use them well, you can get down into the low tenths.

Cheap mikes are much better than they used to be. I just got some from Shars, and I paid around $20 each. I checked them using shop-grade Enco gage blocks, and the figures I got (with bad technique) were 0.0003″ off nominal size. Micrometers come with ground carbide doodads that you are supposed to use to measure accuracy, but they can’t be trusted, so don’t use them. Even lame gage blocks will be within a tenth of nominal size. It sounds crazy to say cheap gage blocks are better than carbide standards, but it’s true. Don’t ask me why.

I took out my new Chinese mikes and put them to work on the part I was making, and I came within half a thousandth. I think. Actually, I guess it could be a little more, since I was getting 0.0003″ of error on the gage blocks. Anyway, the parts were very close to specified size. Much closer than they needed to be. Had I been off by fifteen thousandths, it would not have mattered.

I made this Y-shaped mount thing, and I felt pretty smug. Then I saw that I was supposed to drill a 1/2″-wide hole down the center of it. This is the subtle clue that alerted me to the fact that the part was too thin. So today I had to make a new piece of aluminum so I could redo the part.

I used my table saw to cut a 1″ slice out of a square aluminum rod 3.5″ on a side. Does that sound crazy? It works. I would not cut steel with it, but aluminum cuts beautifully on a table saw, if you go very slowly and use lots of WD40. In five minutes, you can cut something that would take 15 on a little band saw, and you can get accuracy within 5 thousandths.

I never trust the sides of new stock to be square, so after shortening the block to 2.75″, I put it on the mill with a 1/4″ carbide 2-flute cutter and cut a flat side on the top. I put that against the fixed jaw and put a round piece of aluminum between the other jaw and the other side. This allows the flat side to rest firmly on the fixed jaw, to serve as a reference. I made another flat side and ended up doing all four sides.

Now I had a problem. I had four square, flat sides. But I also had two really large sides, perpendicular to the rest, that were neither flat nor parallel. They had saw marks on them. How do you fix a thing like that? You can’t rest it on parallels and mill the upper side, because it won’t rest flat on the parallels. If you put two flat sides against the vise jaws, it will be level in one direction, but it can slope from one side of the vise to the other.

This really bugged me. Finally, I put two flat sides against the vise, snugged it up a little, and bopped it into line with a wooden brush handle. I put a test indicator on the mill spindle with an Indicol holder, and I moved the knee up and down, measuring how far a flat side veered off vertical. I figured that if a side were perfectly vertical, the block had to be positioned correctly. I got it to where it barely moved.

I put a 1/2″ cutter in the mill and took about 0.020″ off the top of the block. I flipped it over, put it on parallels, and did the other side. Then I checked the thickness, which was uniform. I was too lazy to get out the Indicol holder again or use some other method to check squareness, so I put a machinist’s square up against every corner I could find, and I could not see daylight. Good enough.

06 06 14 cnc lathe new block for second try at motor mount

The big lessons I learned over the last month were:

1. Calipers are useless for accuracy below 0.005″, in spite of what people claim about their results.

2. Cheap micrometers are good to under a thousandth. Good ones will get you down close to a tenth, if you have good technique.

3. When buying micrometers, you have to check them using gage blocks, because carbide standards are junk.

4. If you test a micrometer, you have to test it at several settings, because a micrometer which is accurate down near 1″ may be less accurate near 2″.

5. Expensive calipers are a complete waste of money, because they’re still not accurate.

6. Don’t use micrometer ratchets, because they’re not reliable. Learn to tighten them directly, going by feel. This takes practice. Which I haven’t done yet.

I also learned some stuff about lathes. Mainly this: don’t use lube when cutting aluminum with carbide. At least not until you do a finish cut. In my experience, it seems to help the finish a little, but that could be my imagination. I’ve used a lot of WD40. It made a big mess. It was completely unnecessary. Thank God it evaporates, or the garage would be full of it.

Milling lessons I learned: don’t use lube when milling steel with carbide. It stinks and doesn’t really do anything.

None of this stuff applies to steel cutters, and you absolutely must use lube when milling aluminum with carbide, because it will weld itself to the cutter. If you screw up and fill your flutes with aluminum, you can knock it out with a center punch. The punch will catch in the aluminum, and this will keep it from going sideways into the sharpened edge of the mill when you hit it with a hammer. You can also soak it in lye to dissolve the aluminum, but some people think this leaves tiny cracks in the carbide which will make it more likely to break.

While I’m sharing lifesaving information, let me tell you about knurling.

I had to make these knobs for the CNC lathe. They’re 2″ wide, and the narrow part is 1/2″ long and 1″ wide. They’re harder to make than you think.

05 21 14 cnc lathe motor knobs finished

When you knurl, it’s hard to turn the part. The knurls put a lot of pressure on it, so you need to be able to grip it well. How do you do that with a part like the ones I made? If you make the short part and wide part first, and then you knurl the wide part, you have to hold it by a half-inch-long stub. That’s no good. It may spin in the chuck. If you make the whole thing 2″ wide and knurl one end, planning to cut the stub later, how do you hold the part while you cut the stub into it? You can’t, because you’ll have to put the knurled portion into the chuck. That will damage it, although in practice, you can do it with a level of marring which is nearly imperceptible.

Here’s the answer: soft jaws. These are sacrificial non-hardened steel jaws that replace the hardened jaws of your chuck. To hold a part, you run a boring bar into the jaws and make a bore exactly the size of the part. Then when you tighten the jaws on the part, a lot of metal is in contact with it, so you don’t get pressure points that mar the work. You can make soft jaws yourself, but you have to be stupid to do that, because Shars sells them for about twenty bucks.

I don’t have soft jaws. I made the knobs with a knurled portion about an inch long. Then I put the stubs in the vise and turned the knobs carefully, cutting them down to 1/2″ in width. It’s slow and not all that professional, but it works.

You will notice a shimmery sort of line that runs around the knurls. I’ll tell you the reason for that.

I have a scissor knurling tool. The advantage of this is that it squeezes the part from the top and bottom, applying no net sideways force to it. A scissors tool won’t push the part out of the chuck. It’s great. Buy one.

There is a problem with a scissors tool. You can’t gradually increase the pressure, the way you can with a tool that pushes from the side. You have to adjust it in steps, using a nut on top of the tool. The problem with this is that it’s easy to end up with too much pressure. That’s what happened to me.

When you use too much pressure, as you move the tool down the work, it may turn slightly in the toolpost. When that happens, you get that little shimmery band. It’s a very minimal defect. But you don’t want it, so don’t be afraid to make several light passes.

Here’s another great thing to know: you do NOT have to measure the diameter of the work before applying diamond knurls. I had been taught that this was necessary, but that’s wrong. You have to do it with straight knurls, or they won’t mesh on successive turns. But diamond knurls will work on any diameter. Try it and see.

Also, it’s nearly impossible to get a knurled part with a precise specified diameter, because knurling makes the diameter bigger.

I plan to redo these knobs, but with all the false starts and scrapped parts, I considered these adequate for a 1.0 version.

In the past, I tended to do a lot of machining that required little precision. I called it “woodworking with machine tools.” But eventually, you have to get it together. The last couple of weeks have improved my skills a great deal. I hope the things I’ve told you in this blog entry will help you. Believe it or not, it took a lot of practice, reading, and forum begging to get this information.

Og from Neanderpundit may come over and obliterate all of it, but it has worked for me, and I got it from people who are much better at machining than I am. It may not be the best advice available, but it’s pretty good.

The Tower of Gutenberg

Tuesday, May 20th, 2014

Print Your Way to Godhood

Interesting stuff is happening here.

I got my garage fixed up to the point where I can actually use it. I call it the Garage of Shalom. The tools are arranged in a fairly orderly way, there is a nice air conditioner, and the floor is usually safe for bare feet. I am mostly done putting reflective foil in the roof so the AC won’t have to work as hard, and I have a 30″ TV I can use to watch tool DVDs.

Last year I ordered some CNC plans for my mini-lathe. This week I’ve been working on it. Yesterday I bought some metal, and I started working on the knurled knobs that will permit the lathe to be used manually.

Knurling is a bit of a pain, especially when, like me, you don’t practice. Also, there is conflicting information out there about how to do it. Let me clear one thing up, in case you’re a beginning machinist: DIAMOND KNURLS WILL WORK WITH ANY DIAMETER WORK. You will hear people say that you have to measure the circumference and take test passes. That’s true with straight knurls, but diamond knurls will line themselves up somehow. This doesn’t come from me; it comes from an extremely skilled elder machinist. So quit measuring.

I know of two types of knurling tools. One mashes knurls against the work from the side. This pushes the work off-axis and requires lots of force. It’s a bad idea. The other type of tool is called a scissor knurl. It’s like a pair of pliers with a knurl on each jaw. You tighten it up so one knurl is pressing into the top of the work and the other is pressing into the bottom. The forces cancel, so the work is not pushed away from the center axis of the lathe.

One problem with knurling is that it doesn’t like being held in a chuck. You may be able to put a knurled part in a chuck with hard jaws without marring it, but don’t count on it. I’ve found three ways to deal with this issue. 1. Leave the knurling for last, so the part is never held by the knurled portion. 2. Make a longer knurled portion than you need, so you can cut it off after you chuck it to do other operations on the work. 3. Use soft jaws to hold the knurled portion. Number 3 is a lot of work unless you have soft jaws sitting around waiting.

This is a photo of the knob I ruined yesterday. It’s about 2″ wide. I don’t feel bad about destroying it, because it was my second try, and I learned a lot while doing it.

05 20 14 aluminum knob knurled and damaged

This knob is supposed to have a 1″-thick part that attaches to the stepper motor or something. Then it goes to a 2″ knurled portion. The thin part is only 1/2″ long. If you try to grip the knob by the thin part when you knurl it, it will spin in the chuck, because in order to get clearance for cutting tools, you can only put it about 1/4″ into the chuck. That means the way to do it is to make a really long knurled portion, turn the part around, cut the thin part, turn it around again, and trim off the excess knurled part.

I tried to do this, but because I used a short piece of stock, I could only put the knurled part about 3/8″ deep in the chuck, so I had to take shallow cuts when finishing the thin part. I went over 0.050″, and the part came loose and fell in the chip pan. It was ruined. But now I know how to do it next time, and the metal I used was scrap, so who cares?

CNC is interesting to me, because it is part of the developing home-manufacturing revolution. This era started with inkjet printers.

Before there were inkjets, we used keyless electric typewriters that had been interfaced with computers. They were called daisy wheel printers, because they used metal wheels with “petals” that had characters on the ends. The wheels rotated, and the petals where slammed into the paper when the appropriate characters were lined up.

This process worked great, if you were satisfied with what a typewriter could do. When inkjet printers arrived, the world changed, because they could put a tiny dot anywhere on a page. Any image that could be built from dots could be printed. Now we use that concept in forming 3D objects. If you can move a printing jet anywhere you want, you can do the same thing with a cutter, laser, or waterjet.

I don’t know if printers were influenced by CNC, which already existed, or if the eventual merging came via some other route, but at some point we ended up with relatively cheap machinery that essentially printed parts. You can buy a CNC router right now that will allow you to draw something on your PC and then “print” it into wood by moving a router bit over the work. This also works with plasma cutters and water jets, and you can also buy 3D printers that form complex objects gradually from extruded plastic.

I don’t know how close CNC lathes and mills are to that type of interface, but if it isn’t being done right now, it will be this year, because it’s an obvious step in the evolution of home manufacturing.

I’m not that excited about 3D printing right now, because the parts it makes are flimsy. Sooner or later, we’ll be able to make metal and composite parts using printers, and when that happens, people like Barack Obama will start wetting the bed, because it will be impossible to control manufacturing of guns and other weapons.

The lathe I’m fixing up will not be all that exciting, but it will definitly be cool. I don’t know if I’ll be able to make precision tapers (Morse, etcetera), but I should be able to do all sorts of threading, and I should be able to make lots of curved shapes that are difficult to produce on a manual lathe. And things that would now take a day to make will take half an hour or less.

I can’t see myself CNCing my mill, because it’s more complicated than a lathe, and I don’t want to lose manual operation. But at some point, I would like to get a smaller mill and set it up. I’ll put up two videos to show why. The first is a manual mill producing a relatively simple part with a lot of effort and preparation, and the second is a CNC mill doing something difficult in a very short time.

That second mill is a home-converted Grizzly G0704. There is a guy who calls himself “Hoss” who teaches people how to do this conversion. If you’re not impressed by that video, there are surely better ones.

Generally, there are two types of parts made by manual mills: simple, clunky-looking parts produced manually and beautiful, complex parts made using CNC. The computer can easily do things that are hard or impossible for a person, and it can replace a lot of expensive tooling. It multiplies the usefulness of the mill by a big number. And you can have all this for a couple thousand dollars. If you buy a new mill that’s ready to use, you only have to spend about twice that much, and if you think about it, for an average homeowner, over the course of twenty years, that isn’t a big expense. It’s two nice refrigerators, and it will allow you to avoid a lot of expensive repair calls, because you’ll be able to make parts when things break down.

And it’s fun.

Many people who make CNC routers call them milling machines. This leads to confusion, I guess. A true milling machine cuts hard metal with great precision, and it’s a heavy piece of equipment, because you need a lot of iron to resist bending and twisting when the forces are applied. Some CNC routers can cut aluminum fairly well, and for this reason, the people who make them like to call them milling machines. If a milling machine is what you want, a router will probably disappoint you. But it’s still a great tool.

Here’s a CNC router at work.

I’m not watching every second of these videos, so I hope they contain enough information to serve their purpose.

These things print objects. That’s what it boils down to. And you don’t have to apprentice for ten years to run one.

I have to wonder if the government has any idea what’s in store for it. The press was not ready when blogs came along and put it in a chokehold. They can’t control information any more. Now the government is facing the same problem, in a different area. It can’t control manufacturing. It never could, but it is now losing control to an unprecedented degree.

People are drawing up plans for firearms. The government is trying to prevent the plans from getting out, but even the NSA, which keeps its nose up our rear ends every second of our lives, can’t control flash drives and private networks. The government’s nerds aren’t as good or as numerous as the non-government nerds. They will never be able to keep up.

We are getting more powerful. There is no way to stop it. New moral challenges are looming. If the government can’t stop us, what will? I’m glad Tea Partiers and Christians are empowered, but what about jihadists and enviro-terrorists? The stupid, heartless, clumsy government has too much power. Internet nuts have too much power. It’s not confined to good people. And there is no possible way to regulate any of this effectively. We might be able to do something with Uncle Sam, but everyone else is on the honor system. And there isn’t much honor.

Whatever. I want a CNC lathe. I may want to CNC my plasma cutter. I want a CNC mill and maybe a router. And if 3D printing ever becomes useful, I want that, too. I do not want to build bombs or automatic weapons, unlike many people who want these tools. I just want to be able to make stuff and “discover my hands.”

When the Internet was young, we didn’t see the changes it would bring. We still don’t see the future impact of the printing revolution. Life is going to be very weird when three homes on every block have CNC tools. I think the patent office is going to have a lot of new business, and so will lawyers who sue for infringement.

When God created man, he knew that we had the capacity to become gods. He knew that if he left us alone long enough, we would be capable of incredible feats. I suppose that’s why hell exists. The beings that refuse to submit have to be caged, or sooner or later they will do damage so great we can’t conceive its magnitude. In the relatively near future, we are going to see what happens when man can’t be controlled. It may be quite a show.

And now, for no good reason, a photo of the godson.

05 19 14 noah PJs

Black Socks, Bermuda Shorts, and a Warm Ma Deuce

Thursday, August 29th, 2013

The Dream is Within Reach

I had the funniest experience yesterday.

I was watching American Pickers, the show about the guys who drive around buying old stuff other people have hoarded. They resell it, usually at about a 100% markup. They burrow through barns and attics, and they meet all sorts of interesting people. Very often, they end up on big properties with one or more outbuildings, and the buildings are full of junk.

Yesterday, they took a random right turn and ended up on a dirt road which had not been selected in advance (supposedly). They went past a “KEEP OUT” sign and stopped at a building resembling a garage. They hollered and went in, and they found two weird old guys playing homemade musical instruments. They were surrounded by tools and knickknacks.

I heard myself think, “THIS IS HOW I WANT TO LIVE.”

Not so much the sitting around with another old guy, playing music on an instrument made from a plunger handle and a Chock Full of Nuts can. Not that part. The part I liked was being a good distance off the road, on a big property, with no one aggravating me. In a building with concrete walls. Surrounded by cool stuff.

They visited another guy later. He was some sort of engineer, I think. I don’t remember. Naval something or other. He had a lathe, a huge bending brake, lots of grinders, a giant vault, and God knows what else. There were old tin toys there. He had a wooden wind-tunnel model of a plane; his uncle had built it for some outfit that was trying to make supersonic aircraft.

I realized one of the major differences between my garage and his shop was character. He was doing more to keep his junk ordered. I tend to avoid the garage in the summer, because the heat is bad, and a couple of pieces of garage door insulation fell off a while back, which made things worse. The garage was a big mess.

Day before yesterday I went out and fixed the insulation and straightened up a little. After I watched the pickers show, I continued. I went back to work on my garlic press project. You can’t really clean up a shop if there are old projects lying around.

In cross-section, from the side, the press is an H. It’s a stainless tube blocked by a plate about halfway down. The plate will have holes in it, and there will be a plunger which mashes garlic through the holes. Think of a hypodermic syringe with a sieve instead of a needle at the end. Sort of like that.

I had a cylinder made, and I had bored out one end of it. I needed to bore the other end, leaving a 0.10″-thick plate in the tube, for the holes to go through. I considered doing this on the lathe, but the steel I’m using throws ungodly long chips, so I stuck it on the mill and used a 1/2″ end mill.

08 28 13 garlic press body on rotary table

It took forever, dropping down 0.025″ at a time and going through 360° of rotation, but I got it done. Now I have to radius the sharp edges and drill the holes. The plunger is already done. It fits so well, when you drop it in the press, it sinks in very slowly, because it’s hard for the air under it to escape.

That’s cool. I like to drop the plunger over and over and watch it sink.

It’s looking more and more like I’m getting out of here. God be praised. I would say that even if I were an atheist. I do NOT NOT NOT like Miami. I want to be able to go outside and walk a hundred yards before hitting a property line. I want to hear English once in a while. I want to be able to wear long pants occasionally. I want to be able to drive ten miles in less than twenty minutes.

My dad has a 46-foot boat which has been a problem. He uses it as a place to hide out, which is fine, but it’s his main motivation for staying in Miami. I can’t let his hobby ruin my life. I want him to enjoy himself, but this is too much to ask. He doesn’t want me to move 700 miles away, and I understand that, because of his age. I’m against it, too. But if I have to leave without him, I will do it, because this place is not right for me.

Today he started talking about selling the boat. Thank you, Lord. He could keep it in Pensacola (currently my preferred destination), and maybe that’s the better option, but I’m glad to see him consider unloading it. It shows God is breaking things loose.

I am not excited about practicing law, but it’s a pleasant way to earn money, and if I can do it up there and generate income without becoming a cubicle slave, you better believe I’ll do it and be grateful.

Some people need room. I guess I’m one of them. I have several worthwhile hobbies you can’t indulge in a small suburban house. I want to be able to shoot on my own land. I need a shop with an area of at least 800 square feet. I need a normal-sized kitchen. Until I get these things, I’m going to feel like I’m wearing a burlap straitjacket.

I feel bad for my dad. Rejecting God preserves your pride, but it costs you peace and satisfaction. God is ordering my path, and he would gladly order my dad’s path, too, if he would give in.

I’ve located some tempting properties in the 20-acre range. That will suffice. I’d rather have a hundred, but from this chair, I can see three houses without standing up, so 20 will seem like heaven itself.

Prayer in tongues lines things up. It makes things happen. People reject this advice. I can’t help that. I put it out there. Benefit from it or don’t. At least I can say I told you.

Hopefully by this time next year, I’ll have a shop and some tomato plants. That would sure be nice.

Smaller, Worse, Slower

Monday, February 18th, 2013

America’s New Slogan

Last night I had a remarkable experience. I watched the James Bond movie, Skyfall.

It’s remarkable that I sat through it. Skyfall is a truly terrible movie. They have the best James Bond ever, and they’ve already destroyed and abandoned the character. It also looks like they’re hiring people’s girlfriends to write the scripts. But apart from that, I was amazed by what it showed me about the world.

Part of the movie took place in Shanghai. According to Wikipedia, Shanghai is twice the size of Los Angeles. The population is around 23,000,000.

They showed some night scenes, shot from the air. You could shove New York inside this place and never notice it. It’s gigantic. And the buildings are gorgeous. They’re new. They’re clean. They’re immense. They’re lit up with all sorts of electric displays. Lights. Moving advertisements. It looks like a carnival for giants.

The streets are filled, not with bicycles or pedestrian traffic, but with cars, trucks, and buses. The roads are modern.

It buries anything America has to offer. It’s not even a contest. Our cities look puny and dirty by comparison. They look poor.

Shanghai has three buildings over 400 meters in height, and it will have a fourth in 2014. The entire US has two, and they would rank third and fourth in present-day Shanghai. Take a look at this page to see what has happened in Shanghai: Shanghai: 1990 vs. 2010.

We have lost. That’s what the movie showed me. Our economy is still bigger than theirs, but they’re on the way up, and we’re on the way down, and unlike us, they still believe in “bigger, better, faster.” Their human rights record is dismal, and they have a lot of pollution, but they are still leaving us in the dust, and even if they cleaned up and treated their citizens better, that would not change. Critics love to point to the pollution and oppression, as if these things somehow generated China’s prosperity, but they’re wrong. It came from hard work, and from our disobedience to God. These people are our enemies, and God has stopped restraining them, just as he has stopped restraining the anti-progress leftist nuts who used to lose elections here in the US.

A long time ago, I realized that a man’s sins can breed and feed an giant enemy who sits beneath the horizon. You may think nothing you brings consequences, but somewhere, an angry behemoth may be dining on your wickedness, and one day, he may step over the horizon in the blink of an eye and destroy you. It happened to the ancient Jews more than once, and it can happen to us.

Shanghai is just one city, in one country. What about Mumbai? What about Moscow? Xingdao, Beijing, Hong Kong…go to Ebay and look for tools, and see the place names that come up.

When China goes after Taiwan, we will back down. They’re going to be ready, armed with weapons we paid for, and we’re going to be mumbling “Believe in America” and “You didn’t build that.” The socialists and America-worshipers will have to drop to their knees and say, “Enjoy your new province.”

America isn’t going to be restored unless we repent and pray. It may already be too late for our nation, but you can still save your family.

GPS Without Transistors

Thursday, January 10th, 2013

Follow the Pillar of Fire

I want to pass on a little advice. It’s a piece of knowledge that has been useful to me.

As many Christians know, the Bible is like the Constitution (or any other set of laws). It provides many benefits, but you won’t necessarily receive them unless you apply. It’s like the Fifth Amendment. The cops can’t question you after say you want an attorney, but if you don’t assert your right, they’ll question you anyway. There are many things God will do for you whether or not you ask, but on the whole, it’s best to make your needs known and stand on God’s promises.

Here’s a promise which is particularly useful: “The steps of a good man are ordered by the Lord: and he delighteth in his way. Though he fall, he shall not be utterly cast down: for the Lord upholdeth him with his hand.” That’s Psalm 37, verses 23 and 24. It’s clearly a general promise available to all. It doesn’t say “a good Jewish man” or “a good man who sacrifices at the temple” or “a good man with freckles.”

Lately, I’ve been bringing this promise up in prayer, more than once a day. I ask God to honor it until the next time I ask. I believe prayer is like manna in that you shouldn’t rely on yesterday’s ration, so I think it’s important to ask repeatedly and not to expect the prayer to keep you going for the rest of your life. There are some things you only have to ask for once, or which you can stop asking for, once God confirms he will do what you want, but it pays not to take chances.

I remind him of similar promises. The Bible says that when your father and mother forsake you, the Lord will take you up. It says you will hear his voice behind you, telling you which way to turn. It says he will lead you in the paths of righteousness for his name’s sake.

I also ask God to lead my enemies onto the points of their own swords and to hold them there until they repent.

What I’ve found is that when I make this request, things go better. There is less dead time in the day. I get things done. I spend less time goofing off or wandering in confusion. Life is more organized. There is less stress.

This prayer got me over the hump with CAD software. As I wrote earlier, I’m finally able to use it. And it has also led to greater musical productivity. I’m getting all sorts of good melodies written down. I really think I’m going to get to the point where I’ll be selling music. It’s going to be good enough to publish. That’s amazing. Music can be extremely lucrative. You only need one successful work to keep you fed and clothed when you’re retired.

I suggest you try asking God for guidance, daily. See what happens.

I’m very excited about music, because I’ve come to realize that writing music requires the same gift as cooking. It’s really no different. When you write recipes, it comes from inspiration. You’ll be sitting around thinking about other things, and suddenly you’ll imagine a flavor or a texture, and the way to create it, and you’ll write it down and try it. Your imagination tells you what will taste good, and your work only serves to confirm it. When you write music, melodies that “taste good” to the ear come into your mind, and all you have to do is write them in musical notation. If it sounds good, it IS good. That’s the only test.

I find that God is as willing to give me tunes as he is recipes. And here’s one great thing about music: you don’t have to make a mess in order to create it. You don’t have to drive to the store and buy food. You don’t have to wreck the kitchen. And when it’s done, you can preserve it forever, and you can email it and publish it with very little effort.

I don’t know how I would go about finding a market for music, but I’m sure there’s a way. When I have a portfolio built up, I should be able to do something with it.

I consider myself a writer and a creator of music. I think those are the things I should focus on. The other stuff is great, but I believe it deserves less priority. No one will ever pay me to run a lathe, and no one will ever draw closer to God while listening to me make a pizza.

I’ll put up the piece I’m working on now. I was shooting for something resembing a spiritual, but it has more of a classical sound. I love classical music. There’s no reason why I can’t enjoy writing it. I know it’s not fashionable, and composers are expected to come up with inventive new forms of music no one can stand to listen to, but only a moron would say the genre is exhausted. There is a lot of classical music, but only some of it is truly great. There is still a big need to fill. I’m always frustrated because my favorite composers (Chopin, Debussy, Rachmaninoff, and Beethoven) didn’t leave more work, and I’m sure other people feel the same way.

Chopin actually had some of his works burned when he died. Unbelievable.

This piece isn’t done. It’s very short, and there are lots of things I may want to do with it. But it does show that things are going well.

12 31 E Minor Piece

Get connected to the power supply and see what God will do for you. I think he is leading a lot of people out of the spiritual dark ages.

Chewing Through the Straps

Wednesday, January 2nd, 2013

Observations From the Life of a Runaway Slave

More stuff is breaking loose in my life.

For as long as I can remember, I’ve wanted to be able to use tools. I wanted to be able to fix things and make things. A few years ago, I started making it happen. I got a table saw, milling machine, lathe, welder, and a bunch of other stuff. I’ve enjoyed it tremendously, but it seemed like I was being restrained. I was never able to make myself come to terms with CAD software, and there were essential things I chose not to buy, because I was cheap.

Over the last couple of months, I’ve returned to the workshop. I’ve spent some money; a low four-figure sum. I picked up a few little things that made things much, much easier, and plans I had put on the back burner are beginning to come to fruition.

I also got started with CAD. Og and other Internet friends gave me advice about this a few years back, and I tried a few things, but I got nowhere. It was very frustrating. I’m not going to say what my IQ is, but it’s sufficiently high that you would think mastering a piece of software would not be beyond me, and I was completely confused. I could have fixed the problem by spending tons of money on training, but I already felt a little queasy about the money I had spent on tools.

A few weeks back, I started looking at the programs again. Og had recommended Allycad and Alibre Design, and I looked into other things, like Turbocad, Autocad, and Draftsight. I wanted 3D, because I don’t need the aggravation of trying to picture a pile of 2D drawings as an assembled machine, so I ruled out simple, free programs.

I signed up (again) for a free Alibre trial, and once again, I was utterly flummoxed. I could barely draw a line. If you ever want to fully grasp the meaning of the word “counterintuitive,” try this software, or any CAD software. Alibre publishes a book of step-by-step exercises, and I downloaded a few pages, but it turned out the book is completely obsolete. It goes with a user interface which bears little resemblance to the current version and is currently unobtainable. I was going to give up and get Turbocad, plus training, but then I found the Youtube video that appears below.

That guy does everything wrong. Anyone who produces training videos knows that you go step-by-step, and you include every detail. He doesn’t do that. He flies, and he leaves things out. And it WORKS. Watching the video, I managed to draw an oddly-shaped tub with chamfered edges.

That was a breakthrough. Using what I had learned, I was able to go through the first three exercises in the Alibre book. I managed to translate the old interface into the new. Here’s a useless and unrealistic part I created (but did not design).

01 01 13 alibre exercise crank

I say it’s useless because you can’t really attach the flat piece to the handle and axle that way. If it’s a press fit, the thickness of the metal can’t go to zero around the inserted portion of the metal, and there is also nothing there to allow a real-world weld. But that doesn’t matter. I drew it successfully, so now I have a foothold in the world of CAD. I’m ordering the rest of the design book. And I bought the program, which, “coincidentally,” was on sale for 50% off this week.

This may seem unimportant, but it’s a huge leap. The actual work you do when you make things is of trivial importance. What really matters is the design. Most of the act of creation is mental. The actual cutting and welding…that’s just housekeeping. I would rather design a thousand parts and make one than make a thousand and design one. If I can use CAD, I can exercise my creativity, and I can keep the results forever.

You can do all sorts of stuff with CAD. I don’t know much about it, but my impression is that you can send designs by email, print them, use them in patent and product submissions, have parts made from them, and even send them to machines that crank the parts out for you. Compared to anything that existed thirty years ago, that is godlike power.

So I’m happy about that. And I’m getting interested in 3D printers. They make actual parts from sturdy plastic, at a cost which is not prohibitive for a hobbyist. My gut tells me that as the technology advances, ordinary CNC may go the way of manual machining. Who knows what they’ll be able to do with lasers and plasma in the future? Today it’s plastic. Tomorrow, you may be able to cut metal on a printer, in your own house. And prices are dropping. In ten years, everyone will have a 3D printer, or they’ll have them at Home Depot, to be engaged at affordable prices.

This is exciting. It gives individuals a level of control they’ve never had before. Democrats are already wetting their pants over it, because it will make home gun manufacturing easier. There isn’t one thing they can do to stop it. They can pass laws, but we all know how well gun control laws work. And the First Amendment will guarantee that people will be able to pass designs around.

Sooner or later, technology is going to make us so powerful that Democrats are going to have to give up on controlling the means and look toward improving the man. And only God can do that.

I am not interested in printing guns, but the possibility shows how powerful the new technology will be. The printing principal is packed with potential. It provides mankind with a type of leverage that rivals the mental augmentation of computers. In fact, it’s the reason computers exist. If we couldn’t print circuits, the PC would be impossible.

So the CAD thing is good news.

Here’s another thing: I’m getting more original music. I used to have a constant flow of variations on existing tunes, but I wasn’t really able to write original music. Common sense told me the same gift had to be the source of both types of music, but it wasn’t happening for me. Lately, that has changed. I get original tunes more and more often. I got several over the last few days, and they’re not bad. Composition is like cooking with sound, so if you know what tastes good to the ear, you should be able to write good music. I’m going to write some worthwhile stuff, if God stays with me.

I used to be bummed out because I didn’t receive original tunes. Now I realize there’s a new danger. Soon I’m going to receive more tunes than I can finish. What do I do then? I keep reminding myself that it’s better to waste than to want.

It’s wonderful to be able to budget and economize, but truthfully, I don’t think that’s what God intended for us. I think he wanted us to live in such abundance that things would serve us, instead of lack that requires us to serve things. If you have too much, you can focus on what you’re doing. If you have too little, you have to focus on getting more. You shouldn’t serve the dollar; the dollar should serve you. I would rather have more than I need and have to give things away or even throw them out than not have enough. It’s better to receive a hundred tunes and write three than to receive and write one.

Here’s a hard thing to accept: God is not against waste. Or at least, he reckons waste differently than we do. That’s my opinion, based on my observations. Consider the loaves and fishes. Did God pass out just enough? No, he gave the people so much, they had baskets of scraps left over. Consider Solomon. God gave him so much, he really didn’t know what to do with it. Consider the way America used to be blessed. We fed the world, and then we let crops rot, because we had no place to put them. God told the Jews not to harvest every square foot they planted. They were ordered to leave crops untouched, in case the poor wanted them. What we call “waste” is a symptom of abundance.

This principle is found over and over in the Bible. We are told that he who waters will be watered. We’re told that being stingy will make us poor. We’re told that when we’re asked to carry something one mile, we carry it two. God ordered the Jews to give up about 14% of every work week, plus holidays, in times that were very, very hard, when every penny counted. I believe we’re supposed to have and give more than we need. Otherwise, there will always be gaps that aren’t filled.

I don’t think God wants me to work hard. I think he wants me to have ample time to pray and minister every day. I believe that every hour I spend in prayer saves me hours of work, just as the sabbath made the Jews more successful. And I think God is going to give me many more tunes than I can complete. I am an heir, and this is how heirs live. Our cups run over, our yokes are easy, and our burdens are light. Or God is a liar.

I think excessive devotion to work is a Satanic notion. It seems very natural to expect people to earn things. The problem with that is that God wants to give us things that are greater than what we can earn. I believe we limit him when we insist on earning.

Think of the beggar the disciples healed. They didn’t ask him to do their laundry or make a pilgrimage on his belly. They touched him and healed him, for nothing, and he got the use of his legs back. If he had had to earn that, he would have stayed on the ground for the rest of his life.

A while back, some Obama underling told the press the Bible said, “God helps those who help themselves.” Clearly, this person was not familiar with the Bible. The Bible does not say that. It says you shouldn’t be lazy. But it doesn’t say blessings come primarily by, or with the prerequisite of, great effort. Not unless you’re cursed.

Adam didn’t earn the title to the earth or his life of ease in Eden. Noah didn’t earn preservation in the Ark. Lot didn’t earn his angelic rescue. Samson didn’t earn his strength. Gideon didn’t earn his improbable victory. These examples are shown to us to make us understand that faith, submission, and humility are what bring us blessings and power.

Offhand, I can only think of one person in the Bible who thought he had earned his blessings, and that person was Job. And God set him straight, but good.

Satan wants us to think we have to earn things. With this lie, he gets us to devote way too much time to work and way too little time to prayer. And then we don’t get what he promises. For example, you may get rich, but your family may be messed up because you weren’t around to pray for them and teach them.

Prayer is job one. I’m sure of it. Quite literally, prayer is an investment. It is the seed God gives the sower, and in your season, you will get the harvest.

I feel much freer than I did before. I feel like the restraints are being removed. In ignorance, I buried myself in curses, but God is washing me clean and killing their effects.

Spend time praying in tongues every day. Try to make it add up to at least an hour. And pray for God to guide your steps, leading you to the experiences you need to have. Good things will happen. It may take time, as a tree takes time to bear fruit, but it will happen.