Cheap Spring Steel Sheet

Task: Make a needle-valve retainer spring.
This is the little gizmo that goes on a model airplane engine needle
valve, and engages the straight-knurled base of the needle to prevent the
thing from vibrating around.
So -- I'd like to anneal, form, then temper. Any guidance? I've tried
annealing steel music wire, and even though I'm pretty sure that it's
just plain carbon steel, it's so thin that it tempers in air. How does
one anneal thin carbon steel sheet? Or do you just try to draw it until
you can bend it, then re-temper?
The spring needs to be a square "U" shape, with a hole in the bottom and
the top arms formed into shallow "V" shapes to engage the needle valve
knob.
Thanks in advance...
Reply to
Tim Wescott
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I've formed music wire and hard stainless shim stock into fairly sharp bends without annealing them. jsw
Reply to
Jim Wilkins
I do the same with spring wire for lures. Bend to whatever shape I need. Fold it back if needed as well. No problems.
Reply to
Steve W.
Do you think I could get away with doing so with the spring from a tape measure? Or with the steel from McMaster?
Reply to
Tim Wescott
How thick can it be? I have a sheet I got at a garage sale(machine shop) years ago. I could go out to the shop and measure it. Fairly thick, as I recall.
Paul
Reply to
Paul Drahn
AFAIK they are too brittle to reshape. I tried annealing a broken Husqvarna chainsaw starter spring on the woodstove top. 525F didn't soften it enough to bend at all. That was the highest uniform temperature I could reach easily, on a machined flat surface that made good contact over the large area of the recoil spring. If you care to experiment spring temper heat is around 750F, a medium to dark blue.
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"The second method which has been used to good effect involves placing the spring in a small pan containing a few ounces of oil, and then heating the oil until it literally burns off, engulfing the part in a smoky blaze."
It worked when I tried it, though the spring wasn't heavily stressed. IIRC the steel was from a worn-out circular saw blade. When fully hardened it scratched glass. jsw
Reply to
Jim Wilkins
Ive had good luck using a simple propane torch for annealing and then tempering such coil springs in chain saws.
Gunner
The methodology of the left has always been:
1. Lie 2. Repeat the lie as many times as possible 3. Have as many people repeat the lie as often as possible 4. Eventually, the uninformed believe the lie 5. The lie will then be made into some form oflaw 6. Then everyone must conform to the lie
Reply to
Gunner
Come to think of it, I seem to remember an old method of making springs out of carbon-steel hacksaw blades where you annealed them by dipping in oil and burning the oil off with a torch.
If I get a dollar-store tape measure I'll have a lot of material to experiment with.
Reply to
Tim Wescott
I've got a dollar-store 25 footer with a broken spring. The spring didn't last very long. The measure portion looks like new. I think that part (the return spring) is where they cut costs to the bare bone...
Reply to
Leon Fisk
First you take it out........

The methodology of the left has always been:
1. Lie 2. Repeat the lie as many times as possible 3. Have as many people repeat the lie as often as possible 4. Eventually, the uninformed believe the lie 5. The lie will then be made into some form oflaw 6. Then everyone must conform to the lie
Reply to
Gunner
Brownell's has soft spring stock that's easy to file and form. As far as hardening and tempering, cover with soap(or anti-scale), heat it up red-hot and dump into a can of oil. Clean it off, set it on a small plate of steel and heat the plate from the bottom. You may have to make several to get the right color for the spring tension you want. Start with a medium blue for temp, doesn't take long. Alternative is to fire up the lead pot with a thermometer in it, pick the temp for the temper you want, float the sucker on the molten lead, then pick it off and quench. You have better control that way and you can let heavier pieces sit longer at temp so that the crystal structure conversion is complete, it's not instantaneous. Have made leaf and V- springs that way.
Stan
Reply to
Stanley Schaefer
1090 sping steel is what you could use. MSC has it. I used to work at a mu zzleloader shop and when i started they made hundreds of springs individual ly by hand each year. Metal was bent in a vice to get shape or held in plie rs and shaped. Next heated cheery red and dropped into oil.. Then with prop ane heated gently to blue or purple. I'm getting old and memory is getting bad. Important thing was next to test by putting one end in vice and pullin g back and letting it spring. If it bends your temper is wrong. I learned t o rely on the sound. I ended up making bending jigs and doing all the heat treat in an oven. On e at a time for hundreds of pieces was ridiculous as was so much they did. Now out of business. Bad management.
Liked post i copied below
"Brownell's has soft spring stock that's easy to file and form. As far as hardening and tempering, cover with soap(or anti-scale), heat it up red-hot and dump into a can of oil. Clean it off, set it on a small plate of steel and heat the plate from the bottom. You may have to make several to get the right color for the spring tension you want. Start with a medium blue for temp, doesn't take long. Alternative is to fire up the lead pot with a thermometer in it, pick the temp for the temper you want, float the sucker on the molten lead, then pick it off and quench. You have better control that way and you can let heavier pieces sit longer at temp so that the crystal structure conversion is complete, it's not instantaneous. Have made leaf and V- springs that way. "
Reply to
Butter
Alternative that doesn't require tempering is to use phospor bronze. Got any dud switches/relays around? Might be some big enough pieces inside that you could file out something there. Brass shim might work if hammered enough.
Stan
Reply to
Stanley Schaefer
Just be careful that it is not BeCu (Beryllium Copper) instead. You don't want to be filing on that stuff. And yes, it is used in making some switches.
Enjoy, DoN.
Reply to
DoN. Nichols

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