cutting foam feed/speed/depth advice needed

[myxpykalix]

I am working on a project for a client of cutting some flat foam and need some feed/speed/depth of cut and stepover advice for a file i'm working on since my speeds seem to be too long.

I'm not sure what grade foam it will be and since my experience is limited to signfoam I need to get some advice on how fast i can cut and what is the max stepover to use to try to get these times down.

I'm starting with 2.5" foam with a .25 depth of cut to begin with. Can't i give it a fairly large stepover on the rough cut since i am going to come back with a .25 ballnose for the finishing cut?

I'm cutting a 3d model in the foam not just letters for a sign.

[cip]

Jack:

I 3D cut high density foam (2 lb.) using 1/2" ball nose 15000 rpm at 8 - 10 ips up to 4" deep in one pass with .05 step over and get a real nice finished product. I had tooling specially made to handle a 4" deep cut. The tooling was a bit pricey but worth it in the long run.

mike

[myxpykalix]

Hi mike, thanks for the reply...what are your feeds/speeds on the finishing pass? this helps greatly.

[cip]

Jack:
I have never done a finish pass. The foam I used was dense enough that for what my client was doing the finish was just fine. Personally I thought that the finish was perfect for molds and such.

Mike