Treating spring steel stock

[smallpatch]

Ok guys, I’m an idiot.
I’ve used this spring stock from MBS  before, but not very often. So every time, I need to re educate myself on heat treating.
I guess heat to red and quench, but I’m not sure on the tempering time and duration.
I know Taylor has helped me before, maybe he will chime in.
All other input appreciated.

[D. Taylor Sapergia]

Dane, yes heat to cherry red (non-magnectic) and quench in oil...I use Canola oil.  Polish to mirror bright again, and place spring on a thck piece of metal.  I use copper at 1/4" thick.  Drill a shallow hole for the tit so that the spring lays level against the copper.  Clamp the copper plate in a machinist's vise by the corners and  Heat from below with a torch, moving the torch to heat the copper evenly.  Alternatively, heat the copper plate on an electric element.  I place a drop of motor oil on the plate so that I can tell when the colours are about to change.  Heat the copper plate until you see the colours run through the spring...yellow, straw, brown, purple, brilliant blue.  At this point remove the heat from the plate and allow the whole affair to cool to room temperature.  Now you should be able to compress the spring '
til the leaves touch, then un-compress and the spring should not have lost any arc. 
Others will have their own system that works for them.  The steel i use was given generously to me from Bob Roller and it makes excellent springs, using this system.
Good luck.

[smallpatch]

Taylor,
Sounds like you’re talking mainspring.  This is a patch box spring to keep the lid closed. .030” flat stock.
I guess I could do the same laying it on its side on the plate?

[Bob Roller]

That steel was #1075 and I have used it for decades.I have some from MBS that is .030 thick and use it for front trigger springs on set triggers and .093 for the main spring on the rear trigger.Heat to bright orange and quench in my old motor oil drained from a diesel bus engine in the early 1960's.Use a magnet to get the spring out of the oil and wipe it off with shop rag and polish and using a modified Bernzomatic torch draw it slowly and follow the blue with the flame from the torch,then let it cool and flex it.If it's a "V" spring such as a
lock mainspring I hook it to the link and roll it thru the cocking cycle a few times.It's been a while since I have made any springs at all but
this method has worked for me with locks and trigger all over the world and so far,no reported breaks.
Bob Roller

[TommyG]

I use my leadpot with a digital temp probe.  Heat to orange, quench in oil, polish the spring and give it a lead bath at 740 degress for about a half hour.  Did this for all my patchbox springs.  I usually wire the springs to an old heavy nut so they stay immersed in the lead.

[bobw]

I have used all the above methods and all work well.  I have also used the motor oil burn off method that works for small springs but not so much for larger ones like main springs.  During tempering, too hot you have a weak spring too cold it will be brittle.  if you look at tempering charts blue, as the others have said, is in the 600 degree range.  I temper ihe 625 range, using 1075 and 1080 steel, and have very good luck.  My springs are used in custom single shot rifles.  Making springs is not rocket science, most anyone sould be able to make one with some care and attention to detail as descibed in these posts.

[smallpatch]

Thanks guys for all the responses.
Will give it a go later today.
Will let you know how it goes.

[smallpatch]

Taylor and Bob,
Well, it worked like a charm! Nice spring, flexes and returns to where it was before.
Now to figure out a catch/ release for this little cap box.

Thanks so much guys.

[D. Taylor Sapergia]

Dane:  for patchbox springs such as the kick-up spring, I grind them out of old hacksaw blades, polish them bright, heat to red in a propane flame, quench in oil, re-polish, and temper in a soft propane flame to brilliant blue...let cool - don't quench.  They have lots of kick and I've never had one break.