Hi Gary
I not sure if this will help,,, They make saw blades to cut plexiglass most have 80 teeth or more and they make router bits just for doing the same job..
They have many flutes, I have two that I got from Grizzly but I can find the part number for them on the net or in the book from Grizzly..
If you hit plexiglass on the edge it will break the same thing is true if you use a standard router bit it's hitting the edge with a very small hammer in a way it maybe spinning at 20,000 rpm but it's still flat so to speak...
most router bits have only two cutting flutes some have 3 but the plastic cutting router bits have as many as 15 or 20 flutes and they just take a very small bit at that..so you could say that it's always on the plastic like a soild rod...almost at 20,000 rpm's
If you want to see it just ask and I will post a snapshot of one...
Here's one that only has 3 flutes but made for plastic but it's small.
http://www.precisebits.com/products...&I1.x=8&I1.y=12
Here's one more,Fish tail point eliminates backside breakout and splinterin.
http://www.precisebits.com/products...I1.x=10&I1.y=10 http://www.precisebits.com/products...I1.x=15&I1.y=13
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