Thread: Help me ID some steel

Do a spark test first there is plenty on web about how to do them and what to look for, is the steel magnetic? Is the bar end colour coded or stamped? Could be a manganese steel though that usually dulls HSS quickly.

Carbide inserts need to be run at higher spindle speeds than HSS . Otherwise the cutting point can rub and dwell in the one spot for too long and absorb excessive heat .
If the steel has a carbon content and already been turned then it is possible that it has already been hardened up by over heating and you are adding more or it's a super hard steel type .
It sounds like a carbon tool steel of some kind.
Coolants are necessary to stop carbon tool steels from getting too hot or turn them a bit at a time allowing cool down periods.
If you want a steel that will not harden up with turning heat it has to be a no carbon type steel like EN36A or a casehardening steel . That way after the turning is done you cane have it case hardened if it has to resist wear .
HSS steel cutters produce less heat as they cut the steel with a sharper edge. Carbide inserts push the steel off the metal and produce more heat but can do that at extreme speeds.
When roughing a hard steel with carbide inserts an insert with a larger point radius is better at resisting point failure due to heat or interrupted cut.
Then switch to the finer point insert to make a light finishing cut.

Hi Brendan,

Crossfeed's suggestion is a good one.



If you get a bit of known high carbon steel and grind it first to see what the branching pattern of sparks looks like, then try your unknown steel.

Regards
Ray

PS... 1095 spring steel, is a high carbon steel moderately high in manganese... ( I use it on saw blades ) might be a possible candidate..

I possibly have one of these billets as well. Sold as "possibly" 1040 which I think is a medium carbon steel.

I am guessing the heat of previous machining and the cutoff wheel has caused hardening.

Ken