[acecnc]

Hello,

This is my first post so please excuse me if I'm in the wrong forum but I didn't see a topic for plastic.

I am routing .5" HDPE Plastic that happens to need 15 holes per part x 19 parts per sheet. The hole drilling is taking about 30 mins. and every single hole drilled is causing plastic to ball up (see attached photo) on the single flute .25 flat endmill. I would like to find a way to manually drill the holes using a jig or multi-collet drill because I think it would be faster, in the meantime I'm stuck doing it this way.

My machine is set up to run at 200ipm @ 14,000rpm.
.25 single flute (spiral upcut) onsrude.
the hole is .3125 in dia.

Any advice on things to try to keep the plastic from spinning up on the bit?

Thanks for taking your time to read/respond!

[beone]

try dish detergent as a lube

[acecnc]

I've tried everything else... wd40, Pam, oil and air are the ones to come to mind. I will try dish detergent....any particular brand?

I know I'm dulling tools by knocking it off with scrap plastic - it's very annoying!

Thanks for the tip!

[dougie329]

we use compressed air when machining plastic, comes through a regulator and manifold attached to the cnc router and has a locline flex hose to put it where you need. Should solve your problem.

[RJLDesign]

Hi, just a suggestion but I'd try a faster plunge feedrate and use a peck drilling op first using you 2flute before running your nornal mill cycle to open dia. of holes.
(faster feed rates can help reduce heat build up when tool is touching plastic)
Good luck

bobby

[judleroy]

Try using a .3125 two flute instead of a single flute. Also try a chipbreaking bit to keep the chips that are formed small enough not to rap the tool. Try 10,000- 15,000 rpm with a .007-.012 chip load to determine feed. Judleroy

[rowbare]

Try slowing the cutter down a bit maybe 5-7000 rpm.