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The Tower of Gutenberg

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

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2 Responses to “The Tower of Gutenberg”

  1. Og Says:

    run the tailstock in on the part. Even if you don’t have a center hole the tailstock will keep it pushed into the chuck and should give you plenty of room for the knurls.

    You’ll have to leave a ring, or put a short piece of tubing in as a spacer so the knob isn’t pushed into the chuck.

  2. Steve H. Says:

    Those are really good suggestions. Much better than the ones I’ve gotten from other machinists.

    One guy says I should use soft jaws. I know that’s a very workmanlike and proper way to do it, but what a pain.