cutting Styrene hard plastic

[paul60]

Just wonder what type of bit is best used for cutting Styrene .125 material?
Thanks Paul

[Burkhardt]

Why would you even want to cut this nasty stuff (assuming this is pure polystyrene). It is brittle and melts at low temperature. I suspect you need a typical O-flute plastic bit and I would bet you need some cooling by liquid or air.
There are some impact modified PS varieties thay might be better but I would not try. Even ABS, which is such a modified styrene melts easily.

[paul60]

Hi Burkhardt
I received a .125 sheet of this styrene stuff from a sign company, to cut out door hangers for a hotel.
This is the first time i have seen this stuff.
but its not brittle. I can bend and twist it and it dont break.
but it does melt when i cut it.
using a .125 down sprial bit .
cutting at 2ips speed 10000
thanks Paul

[knight_toolworks]

I have cut a lot of this. feel lucky its s 1/8" most of what I cut is .03 thick and it is hard to hold in place and I often need to use a pressure foot. but I can usually get away with a 1/16" straight cut bit if it is sharp. sometimes a 1/16" downcut but it needs to be fresh. I think I use 10k but don't know off hand. but a fresh bit is key.