Sunday, January 13, 2008

Models Undergoing Plastic Surgery


I've been using Art of Illusion to alter some of the Darwin parts. My aim is to make as many of the parts single-head printable. That means eliminating any overhangs greater than 45 degrees. There are quite a few. I've put together a spreadsheet of the models used in the Darwin Cartesian robot and the extruder here. The files marked in red are ones I can't figure out how to fix. I have a zip file of the altered STL files here.

I've been inflicting these models on Vik, who's been attempting to print a Darwin set in PLA. He gave me some tips on how to export STL files from Art of Illusion:

  1. Make sure the object doesn't have any children
  2. Convert to triangle mesh (0.1 accuracy is OK)
  3. Edit mesh
  4. Simplify mesh
  5. Save
  6. Export
I used 0.1 on the "simplify mesh" step as well. The export process can be either ascii or binary; can't be compressed, though.

1 comment:

John Gilmore said...

I had a thought about converting things to reprapable states. This might be a bit out there, but here goes.

I notice that there are quite a few parts that have a right angle, and holes in both sides. I'm thinking of the extruder bracket in particular. What would happen if you turned in on it's back corner, so the two right angle bits are both sticking up at 45 degrees. The bolt holes top edges will then be tilted 45 degrees the other way from whichever side they are in, and there are no overhangs which are more than 45 degrees.

The problem of course is that the "base" of the object is then a line (on-dimensional) line. Pretty tippy! But I think you could add a pair of tabs sticking out on each end and fix that no problem. Like little feet. And if you needed to cut them off later, it wouldn't be too much of a problem.