Favorite Cutters for Plastic? Lathe and Mill work...

A

Arc-On

Aluminum

Joined

Sep 6, 2011

Location

Holland, MI

• Nov 24, 2020

• #1

Hey guys,

I have a production job I will be working on for a customer for a while that is primarily Delrin, with a few parts Nylon.

Mostly turning work, but there will be some milled features after the turning is complete.

What is your favorite tooling for machining Delrin? Mostly interested in nice, smooth finishes and chip control. Parts are anywhere from 2" in dia up to 8", but mostly will run around 2-4" typically.

Mostly looking for your favorite inserts and end mills, but any plastic machining advice is welcome. Mazak QT350 doing the turning and a Hurco 4020 VMC for the milling.

Thanks!

 

Mtndew

Diamond

Joined

Jun 7, 2012

Location

Michigan

• Nov 24, 2020

• #2

Anything uncoated and polished will work and a positive rake.
Delrin won't give you any issues. The nylon will, that shit sucks and never wants to break a chip. Enjoy.

 

michiganbuck

Diamond

Joined

Jun 28, 2012

Location

Mt Clemens, Michigan 48035

• Nov 24, 2020

• #3

Here find an old thread
Machining Delrin

 

Last edited: Nov 24, 2020

Finegrain

Diamond

Joined

Sep 6, 2007

Location

Seattle, Washington

• Nov 24, 2020

• #4

Woo hoo! Lucky you.

I have yet to find a top end for turning and milling acetal/Delrin. Just keep the chips from packing on any inside work. I use the same polished sharp inserts as I use for Al. Watch the drilling especially -- if chips pack it'll make a burned-up mess.

I do use coolant on acetal/Delrin in the mill, as it gives a little better surface finish than dry, and I can blast chips out of pockets.

Regards.

Mike

 

Bluejeep

Hot Rolled

Joined

Aug 3, 2006

Location

Cape Cod, Ma

• Nov 24, 2020

• #5

If your having to turn a lot of nylon use a grooving cycle to rough it out. here is a video I made on a UHMW part that had a bunch of roughing. Dealing with stringy plastics cnc lathe - YouTube
As for inserts anything marketed for aluminum usually works. Milling nylon I would recommend Onsrud O flute cutters. take a diamond hone and hand radius the corner just a bit to improve floor finishes. milling delrin any Virgin Aluminum specific endmill will work well.

 

P

Pete Deal

Titanium

Joined

Apr 10, 2007

Location

Morgantown, WV

• Nov 24, 2020

• #6

I’ve had a lot of high material removal delrin milling this year. I started using coolant but the garbage bags full of coolant soaked chips is a pain. I’m now cutting dry. Can’t see much difference other than I need to stop now and then to blow chips away.

I really like the dlc coated yg1 alu power mills for this. I was using the uncoated ones but i think/hope the dlc coating will keep the edge super sharp longer. This is the key to nice finish- very sharp.

 

A

Arc-On

Aluminum

Joined

Sep 6, 2011

Location

Holland, MI

• Nov 24, 2020

• #7

Thanks guys, I will buy some samples and see what I like.

Is there a consensus on wet vs dry? I would prefer to get away with dry due to the general mess coolant makes and hassle of wet chip disposal, but if there's a good reason to cut wet I'll do it. We run Trim Microsol 585XT at the moment. I've heard stories of various fumes and odors cutting dry, but I don't have any real experience with cutting plastic beyond a handful of parts on manual machines.

 

mhajicek

Diamond

Joined

May 11, 2017

Location

Maple Grove, MN, USA

• Nov 24, 2020

• #8

I cut a certain amount of PEEK. I do it dry, sometimes with air blast. I've found that cutters made for plastic leave a fuzzy finish, but cutters made for aluminum cut clean.

 

S

Schjell

Aluminum

Joined

Jan 16, 2020

• Nov 24, 2020

• #9

I do a lot of POM-C.
Took a while, but now I really plough through that stuff.
I use coolant for drilling & inside turning, but been playing with the idea of fitting a compressed air line to avoid losing coolant.
See attached pic for my feeds and speeds. I use Kenna inserts.