Sear Spring Heat Treat?

[t.caster]

What is a good method to heat treat a sear spring at home with basic equipment. I am having trouble with the spring on a Davis French C lock. It has collapsed so it won't push the sear into the full cock notch! I have to spread the elbow slightly and reharden and temper it.
HELP!

[Bob Roller]

What is a good method to heat treat a sear spring at home with basic equipment. I am having trouble with the spring on a Davis French C lock. It has collapsed so it won't push the sear into the full cock notch! I have to spread the elbow slightly and reharden and temper it.
HELP!

I think that is a sheet steel,rolled spring.I don't use them but you can get
a new one from TOW or Davis.After you have the new one heat the first one red/orange
and spread it out.Reheat to the same color and drop it in a can of light weight motor oil,
after it cools in the oil get it out with a magnet,clean and polish it and reheat until it's a
dark blue and let it cool off.Install it and see what happens.

Bob Roller

[msellers]

Here is a link to a thread on here covering some of the needed info.
http://americanlongrifles.org/forum/index.php?topic=46309.msg455105#msg455105

Mike

[P.W.Berkuta]

Thin flat springs are a bit difficult to heat treat because they do not have much mass and using a torch to do the hardening and tempering is a bit tricky. Heat them too much at the high heat phase and you burn out the carbon and trying to control the temper with a flame is a juggling act to be sure. Experienced people can do it MOST of the time on the first try but for the rest it is a hit or miss process. Bob's advise is a good one - get yourself a spare then play with the original for practice.

[rich pierce]

I hang them from baling wire to heat with a propane torch as above.  To temper I submerge in molten lead for 5 minutes.  I have trouble tempering small springs with direct heat from a torch.

[rick/pa]

Would using a thin steel plate, maybe .040, to heat it on be useful in spreading the heat instead of heating the spring directly?

[Robby]

Yes, that is the proper way to do it.
Robby

[t.caster]

Failure Notice:   After slowly getting it red hot and quenching in motor oil bath, I started to polish it and it snapped in two!

I now have a new one on order from TOTW.

Thanks for all the good advice, though. I will hang on to it for future challenges.

Tom C

[Scota4570]

I have little success heat treating tiny springs.  So, I make them out of flat spring stock (0.030") for Victrolla motors.  I only heat the part to be bent for the screw. Hold in a vice as a heat sink.  I leave the rest alone if at all possible .  If I break a couple I use a wiff of heat to encourage a bend on the tail end.  The material can be cut with tin snips so it goes fast. Don't make a sharp bend, leave a small radius or it will snap.    Your mileage will vary, I cheat.