Can a Chrome Steel hardened Ball Bearing be tempered enough to milled or
drilled?

Some sources suggest heating to a RED temperature, no higher, and then
gradually cooled in fine wood ash or similar. Does this ring true with
any knowledgable folk here?

I am trying to form a branch puller for large diameter copper pipe. I'd
need to cut the 4" ball bearing in half and mill it to the right diameter
needed.

varocketry AT hotmail dotcom

On 30/10/16 20:53, VARocketry wrote:

Can a Chrome Steel hardened Ball Bearing be tempered enough to milled or
drilled?

Some sources suggest heating to a RED temperature, no higher, and then
gradually cooled in fine wood ash or similar. Does this ring true with
any knowledgable folk here?

I am trying to form a branch puller for large diameter copper pipe. I'd
need to cut the 4" ball bearing in half and mill it to the right diameter
needed.

varocketry AT hotmail dotcom
I've done it a few times in the past using a small heat treatment
furnace and it went fine. No special atmosphere and it resulted in
minimal scaling which polished up nicely after machining. I was using
them for ball ends on some metal spinning tools and drilled into them
with HSS drills and while tough it wasn't a problem drilling. The ones I
did were about 1.5" and 3/4". I can't remember the temperature details
as it was over 15 years ago but heated to a red heat IIRC and slow cool
by turning the furnace off.