Saturday, March 31, 2007

plastic fantastic

what a difference a little plastic makes. Maybe the whole should be covered in plastic. make it pretty and people go 'wow'. It really is a shiny pretty world if you don't look too hard. All that plastic is so good at hiding all the flows that lurk below the thin façade.

Made it over to Tap plastics this morning. After I drove half way across town to where they used to be. Of course when I got there I remembered that they're only about a mile away from me now. DOH!
Looked at some sample pieces and talked to a nice kid who seemed to know a bit about how things handled. The polycarbonate (lexan) only comes in clear and smoky clear .. no good for my purposes. I took a sample piece to check out though. Finally settled on some 1/8" black ABS. Its easy to work, no cracking problems, and it's got this cool texture that actually matches the trackball mounting plate.

Heres what I ended up doing. I bought a piece a bit larger than the cp .. in this case 18x36 (about $13). I clamped it over the cp board, drilled holes in 4 corners, put in some screws -- cause I still haven't been able to find cool carriage bolts any smaller than 1/4"... then, once it was held in place, I flipped it over, drilled some pilot holes right through the middle of all the control holes -- including all the screw holes.
Flipped it back over -- so now there's a piece of plastic with a bunch of small holes in it ... and drilled all the 1-1/8" holes with a 5/8" spade bit. For some reason, the 5/8 I had really did a nice job of cutting clean holes in the abs. (Yes, I did spend some time playing with the scrap, drilling holes and figuring out at least 3 ways NOT to do this :D )

Finally .. clamp it all down again, put a 1/2" straight laminate edge trim bit in the router, drop the router into the 5/8 holes, and buzz out all the big holes, including the trackball mount.

Finish up by running the trim bit around the edges. ... Which is where I screwed it up. I kept having to move the clamps and screws so the router could do the various corners .. and the last time ... I forgot to put one of the screws back in, the plastic slipped, and it got trimmed in about 1/4" too far. Luckily it was on the back side of the cp, so I can just take that much off the wood, too and nobody will know the difference but me.

And so it goes .. that's the way it always is... screws up just before you're done ... or maybe I get too excited about getting done and screw up by not thinking towards the end. whatever. It's coming along.

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