Denford Software & Machines

Hi is there anyone out there that has had the following problem:-
For a Yr 7 we do a paperclip project which uses H.I.P.s (high impact polystyrene)as the material as yet i dont seem to have achieved the correct Spindle speed and feed rates for this material. The main problem that I have is the material melting to the tool but this doesnt happen on all the pieces of HIPS that I cut, I have tried numerous combinations but as yet I dont seem to have hit on the right one.
The spindle speed I use is around 3700 and the feed rate is around 700 using a short reach 2mm tool

Can anyone help what little hair I have is getting less!!!

Steve N[/i]

The common problem cutting any plastic when the material melts is that there is insuficient feed. The material melts because of the friction of the tool rubbing the material.

If you were using a thicker tool I would suggest you run at 5000 mm/min

try the spindle speed at 8000 then put the feed to 5000. Try cutting at this and use the feed override to get the optimum. If the plastic melts it wont matter what you do after that point until you clean the tool it will continue to melt.

Also make sure you have TURBO on when you are cutting. This will prevent the tool dwelling at the end of each move ( a point where heat builds up)

Let us know how you get on and the optimum feeds you get.