First I would suggest a hole saw, they are inexpensive, don't require a=20 huge drill to drive it, make a fairly neat hole, and are available in=20 1/16" (1.6 mm) increments. 2nd, a hand held jigsaw with a blade that is thin enough to allow tight=20 radius cuts. Both of these are very common, if can't buy, rental or borrowing should=20 be a possibility. No matter which method, drill briefly and allow material and cutter to=20 cool, and if possible a coolant. If the material melts, a rougher hole=20 happens, and possible to seize tool in hole. 3rd, with dremel, use a 1/8" dia. cutter used to cut wood and drywall=20 like Dremel #560, 561, or Rotozip cutters. Here again material needs to=20 be kept cool. A template that the chuck or smooth part of bit rides on=20 will be helpful, these bits like to wander. If drilling multiple holes in a circle, start with smaller pilot holes,=20 then using progressively larger bits, say start with 1/8" and stop at=20 1/4". In plastic, if the drill gets near an adjacent hole, it might try=20 to walk into the next hole, then it gets messy. On 2/10/2011 11:08 PM, Josh Koffman wrote: > On Thu, Feb 10, 2011 at 10:38 PM, Bob Blick wrote: > =20 >> Immerse it in a pail of water to keep it cool and then use your dremel >> or drill multiple holes in it. >> =20 > My machinist often puts certain plastics in the freezer before > engraving or cutting them. > > Josh > =20 --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .