Need Help!- turning dievar material!!!!

[driftbuster50]

I need help i am turning a hot lathe job and the material is 2" dievar. I have never turned this material before and I am having serious issues making good chips. the part is 12" long going from 2" down to 1.375" i have 100pcs!!!! I tried every speed and feed combo along with different depths of cut. evertime same result real stringy chips that wrap around the part. i have tried several different nose radius tools also. please help!! any advice will be helpfull.

[judleroy]

Ok now for the really scary stuff about plastic turning. I have done this in the past 8 hours a day and it works but it's not for everyone and be careful if you use this method. When you start feeding your cut grab the end of the chip as it starts coming off the part and pull it away from the part kind of like climbing a rope. Just keep pulling till the cut is done. The chips are basically just being manually fed away from the part by you. WARING never rap the chips around your hands or you might lose a finger if the chip catches. Have fun.
Judleroy

[neilw20]

Mount a rotating brush to catch the string.
Unloading it will be a challenge.

[Shane123]

if this material is plastic, i have a couple solutions.....

the sharper the edge prep, the better. no coating on your insert, and possibly grind a nice curved relief. if you can grind it like a snow plow curve, better yet. the harder the feed, the better. I turn uhmw at .03 per rev with a 1/32 radius tool, then skim with a ground insert if customer needs a nice surface. for parting, i use a ground insert and use the air hose to blow the string away. for drilling, even 3/4 inch drill bit, i feed the first .15 at about .03 per rev, and then the rest of the hole at about .08 per rev. The trick with all plastics is to go hard and sharp.

[neilw20]

Want a beautiful almost optical finish?
A quick flash with a flame remelts all the tiny furry bits.
Good on acrylic too.

[machdoc]

I believe this material is a premium hot work tool steel. To avoid long chips in Dievar a typical condition would be: cutting speed 150 m/min, feed rate 0.3 mm per rev, depth of cut 1-2 mm with carbide insert grade Sandvik Coromant CNMG 120408-KM 3205. If heavy notch wear is present it is also recommended to use an entering angle <90º.

[neilw20]

Silly me. Dievar is steel. Other post distracted my brain.
Bohler-Uddeholm U.S.A. - DIEVAR

I've turned stuff like this before. Horrible, high strength string.
I did a pile of initial grooves that created short strings, then the straight cuts kept being interrupted by the grooves.

Messy job!! On okuma lathe.