Boring Nycast Nylon

[jeph_ml]

Good morning folks. I'm trying to turn Nycast 6PA. I am using a sharp, positive rake DCGT iscar insert.
Bore size is 3.5", and I have to take it 3.75" deep.
I just can't finish the bore, chips stay inside and burn up the inside. I've tried pecking, different feeds and speeds and I can't seem to get it right. Last go was at 775sfm, 0.01"/rev and. 125 doc, I'm trying to get it all in one pass. Tried with coolant and without.
Any other ideas for me?

 

[TeachMePlease]

Never done nycast, but one thing I had to get used to with plastics is that even though you CAN run high SFM... You don't alwayas have to.... Drop your SFM and up your feed per rev until the finish no longer acceptable.

 

[jephw]

Slowed down to 500sfm and its working great! Was bumping it up up up instead of trying slower speeds.
Thank you sir.

Never done nycast, but one thing I had to get used to with plastics is that even though you CAN run high SFM... You don't alwayas have to.... Drop your SFM and up your feed per rev until the finish no longer acceptable.

 

[Mtndew]

chips stay inside and burn up the inside.

Feeding from inside out can help with the packed chips also. especially when finishing.