Bored at work, can't work on reprap, so will write about it instead.

I have a phone job with limited internet access. So I have time at work to do a little writing about my experiences so far with reprap.

First off, I don't like Java, and I don't like windows. I'll use windows and even fix it, clean up after viruses etc but only if you're paying me. I'll use java apps generally only if there is no other suitable app. And sometimes I'll even rewrite it in a real language instead if it irritates me enough. I'll try to refrain from further comments about these two subjects though, as reprap is the focus here, not language/os.

I've built a McWire CNC frame, hooked up a pencel and wrote "Hello World!" with it - sortof, anyway. See the thread in "software" forum about the bug in the arduino g-code implementation of the G2/G3 codes.

My McWire differs significantly from the standard. I'm using masonite instead of arcylic, I have no PTFE bearings, my XY table is wider (~24") etc. I have a very limited budget for reprap stuff, and I'm trying to save as much money as I can so I can get the electronics and plastic and such thing where there is no way I'll be able to find something remotely suitable.

Mostly due to my "eh, close enough!" method of engineering, obviously a holdover from my days as a programmer, I've got holes all over it. Places where I put screws in the wrong place or changed the design. I don't have a rail attached to the underside of either the X or Y table for instance. There was too much friction, so I replaced them with pairs of skate bearings instead. I figure the darn thing needs to last through ~100 hours of printing. Then I can throw it away and move the electronics and the extruder over to my shiny new darwin. I'd post pictures, but my camera is at home.

I'm using a set of three found 24v steppers with the found 24v stepper driver board that came with them. Almost all of it is going to be 24V - I've got a few dandy little 24V DC Gearmotors to use for extruders.

Just last night I placed an order with the RRRF for the PWM kit, the DC motor driver kit, Thermosensor kit, 5lbs ABS filament, and a couple feet of nichrome. Cost me ~$95 with shipping. Shipping alone was about $21, I wish it could be shipped book rate or something.

I also ordered 6 .020 drill bits and 6 .013 drill bits (#80 and #76) from [www.micromark.com]. Cost me ~$22.

I'm looking forward to getting all that, but I'm working 68 hour weeks for the next two weeks (partly to pay for all that) and won't have time to work on it till then.

I think I'd need some kind of adapter to put those small bits in my drill. But I'm planning on taking it to a friends house - he has a lathe, a drill press, etc. I'll make a fairly simple extruder barrel first, from some 5/16 rod stock. If that works I'll probably make a second, and if I didn't break all my drill bits to make two extruder barrels, I'll probably try to make the extra hole for the anti-ooze nozzle thingy.

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I'm building it with Baling Wire

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I'll use java apps generally only if there is no other suitable app.

Java apps have a terrible rep. I've never worked out why so many java desktop tools are just so plain awful. It is possible to write high quality, fast, stable java. One day, I'm sure someone will

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And sometimes I'll even rewrite it in a real language instead if it irritates me enough.

What would you class as a real language? If that might include python, you could do worse than looking at skeinforge.

I have the outline of a c++ host here, with the intent of writing something significantly smaller and faster than the java host, and without having to worry about garbage collection interfering with program execution. I'm in no hurry to work upon it further at this point. In the future I'm keen to run a cnc device as a network service from one of my handful of smaller machines, such as a soekris or a netra... but for now I'm more interested in the hardware/firmware side of the project which is where any improvements will make the most impact.

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I'll try to refrain from further comments about these two subjects though, as reprap is the focus here, not language/os.

The host software is largely platform independant, no?

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The host software is largely platform independant, no?

Well, yes. But I'm a bit predjudiced against mswindows too. I guess it's not prejudice really, as I worked technical support for Gateway for six months, and have repaired computers for other people for years. I got tired of constantly dealing... wait a minute. Drat! Nevermind, we're talking about reprap here.

C, python, perl, lua, even lisp, forth, or assembler would be better than... Ug. Let's try again.

I've tried the skeinforge toolset. Enrique did a bang-up job from what I can see. I was extremely impressed by the quality of the documentation in particular. Probably because it's something I tend to slack on.

I hacked a quick send script to interface with the arduino (which is what I'm using, apparently nophead who also uses skienforge is using some other CNC interface) and reset it, send gcode, etc. Enrique's slice software works great. Run it from the command line "skeinforge.py bracket.stl" and it'll spit out a gcode file to feed to the reprap. I love it. I'd prefer more "unixy" configuration files, (#'s for comments and parameter=value) since it would make editing the configuration files by hand a snap. Even putting descriptive comments next to each configuration value. Skeinforge uses .csv files which while technically text aren't really designed to be human-readable/writeable.

I've struggled with the official host software quite a bit. Finally got it to (slowly) pop up an impressive gui, but never got it to complete even a trivial build with the null cartesion bot. I was ecstatic to see a python-only toolset. And command-line driven to boot. BONUS! For awhile it was dependant on AoI, which I've never gotten to work correctly, but now thats completely gone.

So all that I need to do is learn a CAD program. I'm looking a BRL-CAD right now, when I've done those tutorials I'll do the blender CAD tutorials. I think I saw one other mentioned on the forums that looked interesting, "Truespace" but haven't done enough research on that to even know if it'll run on linux.

I've been very impressed with BRL-CAD. Anybody trying to make a open source CAD package would, imho, be better advised to write a graphical interface to the brl-cad libraries. It's great stuff, but the interface is really primitive. I haven't tried my six-axis controller with it, but I'm going to and see if it works. Should be great fun.

Edited 1 time(s). Last edit at 08/30/2008 06:15PM by John Gilmore.

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I'm building it with Baling Wire