The inner layer is just a cutout. I made a pattern of random blocks with connecting lines reminiscent of the patterns on the Millenium Falcon's control surfaces.



Laser engravers are probably the most forgiving CNC tool there is. But it is still good practice to combine your shapes and check for broken and overlapping paths.



To finish off the cutting, there were two special pieces; the "spider" holds the electronics in the center of the box, and the last piece is designed to hold the super-magnets that keep the lid on.



Do I need to point out you can assemble everything in Illustrator (or Inkscape), including reference layers, and by simply turning on and off visibility control what actually gets cut? Also, the color fills here are all for my reference; when I went to print, I selected "vector only" from the print options, thus none of the fill gets engraved; only the surrounding paths get cut.







TechShop will give you a basic class on the Epilog laser engravers before they allow you to use them. There are copies in the laser area of the class handout; specifically, the guide to powers and speeds. These will get you in the ballpark, but you must be prepared to make adjustments.



In the case of these pieces, many are so small I needed to reduce machine speed (as the warning posted near the lasers explains). I was using speeds no higher than 60% during the raster work to keep the print head from slamming back and forth too rapidly and damaging the motors.



For the actual engraving, I started on the low side of the recommended power. My first pieces bowed under the heat of all that engraving. I reduced power again over two more trials on scrap pieces, carefully notating my settings in my notebook as I worked, until I had a nice engraving with minimum distortion.



For the cutting, I started with my own power/speed combination found on a previous run with the same plastic, then modified it from there. You want to avoid having a lot of flare-ups when cutting. This is why the best cut is sometimes to do two passes at a lower power setting - without of course moving the piece between cuts!







In other practical matters? It generally took about four days to get a reservation in on the machines, although I managed to get some cutting done one day by waiting around for someone to finish early on their reserved block. The cut pieces were fast; it took longer to get the plastic in the machine and the print settings checked than it did to actually cut. The engraving, on the other hand, is multiple passes, and took 5-7 minutes for each piece. So get the full two-hour reservation; you'll need it.



(And bring extra material/scraps to experiment with -- I had to cut in three different sessions as I had never quite brought enough with me!)