Need help with a spring

[Dennis Glazener]

I am trying to make a sear spring using a spring from a recoil starter. I get the round part where the anchor screw goes formed fine. I can keep it red while forming the loop for the screw.

When I try to make the bend for the vee part I end up breaking the spring. I can not keep it red while forming the vee. It cools off too quickly and I break it!

I need to aneal the spring  to avoid breakage. Evidently just heating it red and cooling is not enough. Anyone have experience using recoil springs to make vee spring's? How did you aneal the recoil spring?
Dennis

[Acer Saccharum]

If you have lots of lawn mowers left, you can also try sitting the spring material on a steel bar. Heat the steel from underneath until the spring and the bar are red, then slowly withdraw the torch and let air cool.

If that is not soft enough:

Same setup as above, but cover over the spring with wood ash or lime once red. Allow to sit until cool.

If neither of the above works:
Put it in a small can packed with charcoal or iron filings, and bring the whole thing to red heat in a woodstove, fire etc.  Allow to cool slowly in the can. Should be dead soft.

[Dennis Glazener]

If you have lots of lawn mowers left, you can also try sitting the spring material on a steel bar. Heat the steel from underneath until the spring and the bar are red, then slowly withdraw the torch and let air cool.

If that is not soft enough:

Same setup as above, but cover over the spring with wood ash or lime once red. Allow to sit until cool.

If neither of the above works:
Put it in a small can packed with charcoal or iron filings, and bring the whole thing to red heat in a woodstove, fire etc.  Allow to cool slowly in the can. Should be dead soft.

Thanks Tom, will have to try that.
Dennis

[Longknife]

Tom , maybe you are trying to get too tight of a bend. Try making a more  "rounded" bend by wraping it around small drill bit? Ed

[smart dog]

Merry Christmas Dennis and thank you for the ALR website,
I don't understand why you cannot keep the spring red hot while making the bend.  I hold springs by their screw eyes in a vise, heat the bend area with a propane or mapp gas torch and bend my springs with needle-nosed pliers while simultaneously heating them.   However, I do anneal all my spring stock before making springs.  Acer's method should work well.  I am lucky to have a burn-out oven so I can control the heating and cooling process very precisely.

dave

[oldiemkr]

I agree with longknife. Make the bend around a piece of roundstock.

[Nate McKenzie]

Dennis. When you anneal steel, it must be cooled very very slowly as per Acer's instructions.  Hope you and yours had a very Merry Christmas. And yes, thanks for the ALR website.

[Dphariss]

I am trying to make a sear spring using a spring from a recoil starter. I get the round part where the anchor screw goes formed fine. I can keep it red while forming the loop for the screw.

When I try to make the bend for the vee part I end up breaking the spring. I can not keep it red while forming the vee. It cools off too quickly and I break it!

I need to aneal the spring  to avoid breakage. Evidently just heating it red and cooling is not enough. Anyone have experience using recoil springs to make vee spring's? How did you aneal the recoil spring?
Dennis

If its air hardening steel its heck to aneall. May need to be heated then insulated till its cool. In some ash etc. But may need a larger piece heated with it, like Acer said, to keep heat on the part even then to keep it from cooling too fast.

One of the problems with using "found" steel is not knowing the alloy.

Dan

[LRB]

  Even if anealled, you should never bend spring stock unless it is red hot. To do so weakens the spring at the bend, and the damage cannot be undone.

[smallpatch]

DENNIS,

I just use the cold spring materials from MLBS.  You bend and shape cold, then heat to red and quench.  They're not spring, till you heat and quench.  Works great.

[JTR]

I have some of that material that smallpatch mentions, and it works really well! Cheap and easy,,,, unless you have a thing for having a piece of lawnmower in your gun!
John

[Dennis Glazener]

I may have to get some of it! I have tried several different ways and either the vee is not sharp enough (using a bit etc to bend it on) or it breaks in the vee! When the vee is not sharp enough the spring is too wide to work right in the space available. At least I have gotten good at making the rest of the spring! If I could only get one small enough between the leafs of the vee.
Thanks for all the advice,
Dennis

[California Kid]

As JTR says it would be easier to get some annealed spring stock. I use it as well. Have also used hack saw blades and they work well. Steel banding for packing works too. The annealed stuff is much easier to work with though.

[Mark Elliott]

Dennis,

It is practically impossible to anneal such a small part.   What I have done instead, is do all the work hot.    I always use a Mapp or Propane torch to form my springs.   You need to shape and file the spring to the proper profile before bending and make sure that the spring is polished.  There can be no scratches across the steel on such a small part or it will snap.   You then form the bend while the spring is in a vise.  You make the bend by just heating the point where you want to make the bend.   For a sear spring, I would fold the metal over completely and then pry it back open slightly putting another bend halfway between tbe first bend and the bearing tip.    All the bends should be made by heating the point of the bend red hot.    I would then harden by quenching in oil and test the hardness with a file.   If it is hard, I would temper to between 650 deg F and 700 deg F.     I use a heat treat oven now.    In the past I have used a lead pot adjusted to just past the melting poi nt.   I have made lots of springs,  if you are still having problems,  you can come over to my house and we can work on it together.   If all else fails,  I have a good selection of oil hardening, plain carbon, tool steel.  We can certainly get you a spring made up in no time.

Mark E.

[dannybb55]

I am surprised that no one forges theirs. I forged a mainspring for a prototype mule ear lock yesterday. I made it turn corners, tapered and thinned it and put a 90 on the small end. After that I cut it off the bar with the hot set and annealed it on a big hot bar of steel under some dry sand. I'll check on it after feeding the dogs.

[Dennis Glazener]

Dennis,

It is practically impossible to anneal such a small part.   What I have done instead, is do all the work hot.    I always use a Mapp or Propane torch to form my springs.   You need to shape and file the spring to the proper profile before bending and make sure that the spring is polished.  There can be no scratches across the steel on such a small part or it will snap.   You then form the bend while the spring is in a vise.  You make the bend by just heating the point where you want to make the bend.   For a sear spring, I would fold the metal over completely and then pry it back open slightly putting another bend halfway between tbe first bend and the bearing tip.    All the bends should be made by heating the point of the bend red hot.    I would then harden by quenching in oil and test the hardness with a file.   If it is hard, I would temper to between 650 deg F and 700 deg F.     I use a heat treat oven now.    In the past I have used a lead pot adjusted to just past the melting poi nt.   I have made lots of springs,  if you are still having problems,  you can come over to my house and we can work on it together.   If all else fails,  I have a good selection of oil hardening, plain carbon, tool steel.  We can certainly get you a spring made up in no time.

Mark E.

Mark,
Thanks I might have to do that. I am going to try getting my wife to help by keeping the Mapp torch on the bend as I need both hands to work with. If that doesn't work I might call you.
Dennis

[LRB]

  Mark E. is dead on. Follow those instructions, and you should have a fine spring.