steel to use for clutch/brake disks in lathe?

[eeinpa]

Hello. We've been trying to find a source for clutch and brake disks for a metal lathe which is no longer supported. We finally took it apart and measured the disks. We are thinking about just having new disks cut on a waterjet machine, as there really doesn't appear to be any rocket science to them. There is no friction material, just steel and steel disks. The disks are too thin for us to measure their hardness. Can anyone suggest a suitable steel to use to make these?

Thanks!

 

[eeinpa]

BTW, the disks are all a nominal 0.060" (1.5mm) thickness.

 

[unclesyd]

We used a steel from This to make disks for multiple disks clutches and some oddball flexible disks couplings.
I don't have anymore information as to the type or where we purchased it from but it was made by Theis. You might give Theis a call for recommendations and where you might be able to purchase the material as they are mill.

If no joy in this direction I have seen prehardened AISI 1065 used for similar applications.

http://www.theis-usa.com/tpscmain.htm

 

[Compositepro]

Are you sure the friction material hasn't just worn away? I don't think I've ever seen a steel on steel brake. Is it a wet brake?

 

[eeinpa]

I've talked to several people about replacement parts for similar clutches and brakes. They all seem to accept that there is no friction material on any of these disks. Apparently it is not an uncommon approach. It's not even really that the disks appear to be worn, but rather than they lose their temper, gall, score and warp, reducing the contact area and affecting their friction ability.

Yes, these are wet devices. The clutches are in an oil bath gear box that drizzles oil over the disks. The brake disk stack appears to use the oil from its hydraulic actuator to keep the disks coated with oil.

I was thinking of some of the prehardened sheets from McMaster Carr, like 4140/42 or 1075 or 1095. Thanks.