Daily Archives: February 22, 2010

3D printing for the rest of us, The reprap.org project

Recently I have been active posting to the reprap forums. There I started a thread relating to my observations after reading the forums almost daily for a year. This thread can be read on those forums.

I have a rather macabre and dry sense of humor. Much like the mummys here in the hall of mystery.

Reprap is a bit of a mystery. Something real that has come out of what is a dream and a bit of a lie. There is still much promise to be had with the current technology. Most of the old timers must think me a bit loopy as I tend to rant against software versification. That only the newest hardware and software are worth using.

For almost 20 years from 1982 to 1998 I made my living directly off either selling or working on the design QA team of apple products. Steve Jobs was my boss’s boss. We did what Steve wanted. If not, well lets just say Apple no longer designs laser printers. At least my products were a success. The short of it is I use Apple products. I do not download revisions because I am told to. I download what I need when I need it. Because it is a better product.

This is what damaged apple in the late 1990s. I did not agree with it then and do not agree with it now. If it is not broken, there is no need to fix it for the sake the repair bill. Which is usually padded anyway.

If this is how you feel, then stop reading now and return to the facebook fad crowd, because this sheep is an Arcadian sheep, who believes in recycle and re-use. If it is not obsolete, then why bother with it, it will become obsolete soon enough.

So what made Apple great, and why I like so much the work of the Disney brothers is that they produced something new. Reprap is like this a new way of looking at how one can make things.

Unlike the lie of most dreams, reprap has some truth that makes it quite likely to succeed. There are a lot of issues still to be had. One of these issues is speed. This has been a problem with my existing CNC equipment. It is too slow and the design path takes forever. I am lucky if I can scan in a part and make a 3d model in less than 16 to 18 hours.

Then comes the issue of making the part printable. There are several divergent paths for the reprap. The core team made a java applet. This does not work on the mac. Since the hardware was expensive and built to last, there is no one to test the code, so the code sits somewhere in cvs hell. The problem is that most modern programmers depend on the corporate need to upgrade early and often. Little thought is given to simplifying the code to run on the lowest common denominator.

So instead of bothering to fix the mess, a new branch went off using python. So we are in the jungle anyway. One adapts. This is an experiment anyway, with just the right amount of anarchy.

The real gating force is that my machine tools are slow. So the best place to start is with the bottleneck of the 1989 drazzi motor controller. I need to make some rollframe parts for a client, so what better than to upgrade the system and mill these parts. At the same time look into how the system can be improved.

The shop is not really a place for the latest in computer hardware, So the goal is more for an NC controller than a CNC, where the build files can be read off of a smart card. I already have the electronics for reading compact flash card MIDI, so making these changes should be quick. We will see. a days project turned into a week, and is more likely to take a month.

The real question is making the motors move. In practice we are just drawing a picture. In 1773, Swiss engineers could do this with cams, so it must be a trivial process. The Swiss even used a Z axis on the pen or pencil so the final pictures look hand drawn. The doll that draws with a pen even knows when to shake the ink from the tip. The artist doll with a pencil blows the dust away.

Of course the french kings that these toys were made for were beheaded, But that is only poor solution to the problems of management. The new managers, were quick to realize that scaled up these simple toys could be used to rivet battleships automatically. This was also a simple solution to the Irish problem. Since automation did away with labor.

As I have noted, my late friend John Grass sold me the machine to prove a point. That one needed to understand the basics first. I was the only one who could make the drazzi work. It only would run one program and draw a picture of a running horse. The reprap seems to have the same issue, it currently is designed to keep the unemployed labor occupied dreaming of change, and not of what is needed.