Need Help!- TRYING to turn AMS 5737 screws...

[PoiToi]

Hello all, we have an order for some specialized screws made from some stock screws supplied by a customer. they are 8-32, and just need to be shortened and have a chamfer put on the end.
The material for the screws says it's "AMS 5737", and I cant find any info on what this is.
anyway,I ask because it chews up tools like nothing. HSS will dull out and stop cutting after 10 or so parts, and carbide just chips out immeadiately.

can anyone shed some light on what i'm dealing with and how to cut it?? We are cutting them off in our 2nd op department on a hand screw machine, with oil.
thanks!!

[g-codeguy]

I found 5737M. It is 15Cr, 25.5Ni, 1.2Mo, 2.1Ti, 0.006B, 0.30V
Numbers next to it in the AMS Index book are S66286 and A286. Bet they are HARD. Try carbide again, but drop the SFM waaaay down, make shallow DOCs at slow feedrates. Good luck.

[PoiToi]

yeah, i noticed it was HARD..... >_<

i'm prety sure they are heat treated, too. i'm not sure if that would help of hinder me in this case...

i've tried anywhere from 1200 RPM to 4 or 500 RPM with the same results.... its an 8-32 screw. i'll mess with the setup a little and see what i can get.

thanks for the info!!

[little bubba]

Been there and done that, several different ways. Sometimes turning them is just not worth it.

Sometimes a cutoff wheel in a small fixture or mounted to a tool post grinder and belt sand your chamfer on. If your people are steady and have good eyes holding .010 on length shouldn't be a problem. I've had part timers that could just hit 'em nuts everytime, 100's of 'em. Some monkeys just never get it though.

BTW, A286 sucks, think inconel light, one of the trade names is Incoloy.

[g-codeguy]

Do you have a Top Notch ceramic insert you could try? We got back some heat-treated outer races that had the snap ring groove too narrow and under size. 52100 Rc58-Rc60 neighborhood, I believe. I used a .062 wide ceramic insert to do the re-groove. Worked pretty good. Course I didn't have quite the situation you've got.

[widetrack]

THe A286 material is high in nickel and chrome. the sfm should be slow, the chip load should stay heavy, but not in the doc. forget the high speed steel, it will never fly, go rich on the coolant mix. the prob is the 8-32 is so small, what I've done is make a plate (2 actually) screw the things in from the bottom, mill all and I made a plunge cutter to cut the chamfer. do about 20 at a time , reload the other plate while the first is running. good luck.