Feed Rates for cutting PVC

[davidp]

Hi all,

I have a job coming up cutting 135mm dia (5 1/2") circles from 15mm (5/8") PVC. The part also has 5mm holes drilled approx 12mm in from outer edge and an inner profile as well.

My question is what chipload should I be looking at to achieve a smooth cut.

What strategies have others used cutting PVC. Any assistance or advice on do's and dont's would be appreciated.

Regards,

David.

[Brady Watson]

David,
What kind of PVC? Sintra/Komatex etc expanded foam PVC or rigid gray PVC?

-B

[davidp]

Brady,

It is rigid gray PVC.

Any Hints tips infor would be appreciated.


Regards,

David

[Gary Campbell]

David...
I have done some cutting in the rigid gray pvc as our table and plenum is made from it. SHARP endmills are OK but not as good as O Flutes. Keep bit as short as possible to avoid chatter if making agressive cuts. Get the RPM as low as possible to avoid heat. When we did the spoil board I used a 3/8 2 fl BN @ 1.5 ips around 8500 rpm. 1st pass @ .25 deep and 2nd @ .318. We used a 1/4 sgl O flute for the perimeter gasket and it cut much better.

Try toolpathing at 1 ips and 10K rpm. Then bring rpm down until bit scream goes away. Then bump up speed till you get nice curls off the bit. Keep the DC hoses clear!!
Gary

[davidp]

Gary,

Thank you. I suspected that my RPM was too high around 14,000. I used a 1/4 single O flute at around 70 mm per second (approx 2.6 ips) a 8mm per pass.

I will slow everthing down and I will post the results.

Regards,

David