Hey guys, recently I was playing around trying to cut some lexan on my mill. I was pocketing out some text that I had inserted from Vcarve, then converted the text to curves so I could pocket it out. The first attempt worked not too bad, but I had a lot of fuzzy burrs around all the edges, which was way too much to have to clean up, besides when cleaning lexan, any slips will badly scratch your material. I did a couple more of the same engraving, but this time I gave the project a periodic spray of WD-40. This solved all my problems. The finish cut was clean, almost no burrs at all, and any that I did have cleaned off with a finger nail. I was using Vcarve for the pocketing routine, and a nice new sharp 3/32 3 flute end mill for the pocketing. All I got was a bunch of really small chips and very little mess. The WD-40 cleans up easily with some soap and water.
Speeds and feeds were about 2400 rpm on the cutter and 20 ipm feed.
The 5 letters (AFIRS) cut out at .040 deep took about 15 minutes.
Give the WD-40 a try, it might work for you as well.
I really prefer not to have to engrave into lexan as it is so soft, that it scratches so easily. I would much rather use Corian.
If you guys are looking for sources of free Corian, check out any local cabinet / counter top fabricators that use Corian or similar products. If you offer to do a bit of engraving for them from time to time, they will most likely give you all their scrap sink cutouts etc. The sink cutouts make really good custom cutting boards, for their customers.
Corian is really nice to cut, almost any speed and feed seems to work. I have tried everything from about 5 ipm to 40 ipm and with speeds of 2400 and 15000. I get no problems, and the chips come off like thin feathers - easy cleanup and no melting of the material on the cutter - so far. I did find that at 2400 rpm on my mill, that I had to keep the feed below 30 ipm, or else I started to get rough sides on the cut, just due to too fast a feed rate for the rpm being used.