I have made a new tail-spring out of 251A58 steel – the parts are about 33cm x 3.8cm x 4mm in size. Now I need to get it hardened and it needs to be quenched in oil. Does anybody have any ideas about companies who might be able to do that and send the parts back to me by post? (I’m UK based)
I would google on toolmakers.
Heat treatment of carbon steel is usually a hardening followed by annealing ie two stages.
Yes, it needs to be heated, quenched in oil, then annealed. I’ve done it myself for smaller things, but I’m somewhat apprehensive about the practical side of plunging a large lump of glowing metal into oil.
If you can borrow a furnace with accurate temperature control then it’s easy.
A pottery workshop?
The oil is ok. It makes a lot of smoke. Don’t do it in the kitchen 
http://www.ttigroup.co.uk/
one of the best places in the uk!!!!
