Melev & H2OENG,
I know this may sound stupid but I have only used my router for wood in the past and recently tried to do a test piece of lexan only to have it explode into tiny flying shards (glad I wear gloves now!).
Do you run the peice with or against the spin of the bit? I didn't think that 3/8ths would be too much going against the spin but I do now!
BTW, I finnally made an upflow filter for resins that works! I'll send you a pic if ya want, just wished I had used a router to clean it up some.