Need help with machining parameters

[tex]

I have to machine a part out of Delrin, Plexi or Lexan. Will use 2mm diameter endmill on a machine with max spindle speed of 7500 RPM and 20 HP motor.

I need an advice on machining parameters:
- should I cut deeper than 1mm in a single pass?
- what would be the highest acceptable federate with cooling on?

[tex]

Any ideas...?..please...

[wjbzone]

I think your limit will depend on how well the chips are flushed out. If you cant get the chips out you will need to back off your depth or feedrate. I would think you should be able to cut at least 4mm deep with a 2mm dia tool. The optimum depth feedrate combo will depend on type of cutter (ie number flutes, helix angle).

I would just keep pushing it harder until you have problems and then back off. Lexan cuts easy.
Bill

[coherent]

I think the answer depends on your endmill... is it single, double flute, is it carbide, or hs steel, and so on. I've seen these type of questions before and the best answer is check with the bit manufacturer or find a simular bit online and check the recommended spindle speed, cutting speed and cutting depth. Anything else would just be an (un)educated guess without the specifics I'd think.
-marc

[tex]

Thank you both for your answers.

About the endmill: it is either two-flute or four-flute carbide one. On the manufacturer's site I was not able to find recommended cut speeds and depths, so I'll go for 2-4mm cut depth and at least 20IPM with 7000RPM spindle speed. The machinist will be able to change feedrate and RPM easily on site.