1095 tempering for springs

SDS

SDS

Joined
Oct 22, 2007
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Can someone please point me towards some information on tempering a slip joint spring from 1095? I can find information on how to harden it but I'm having some trouble getting information about tempering.

I have heard that you can torch the spring to bring the hardness down but I have been told to torch the front (blade side) or to torch the back side. I've also been told to heat a scrap of steel and use that to transfer heat to the spring.

Thanks for any help.
SDS
 
I do my spring tempering with a torch. Fully harden the spring. Then clean it up so you can see the steel. I hold it as far to the rear as I can with some pliers and slowly heat the whole thing with a torch. It does not take long or much heat so keep the torch moving. You are going for a nice blue color, light blue. Then quench in oil. Then clean up the spring and repeat. I do this 3 times and have never broken a spring.
 
That SOUNDS easy enough. I'll give that a try. Thank you.

SDS
 
I temper mine in molten lead at about the same temp as Bruce uses.
 
The tempering oven , salts, or lead will give an accurate temper. This is the best way. A torch will work, but results may vary greatly.

I don't recommend the following technique, but here is a good example of Bill Moran's unique brand of metallurgy.

Bill Moran told me how he tempered all the springs he made.
He had a black ,charred looking baking pan that sat beside his forge ( you may have noticed it in his shop). He would get the coals burning real low. Then he laid the springs in the pan, added kerosene (yes kerosene) until it just covered the springs. He set the pan on the coals, letting the kerosene heat up, ignite, and start to burn ( This happens at about 550F). He would pull the pan off the coals before the kerosene was gone, and set it on his anvil to finish burning and cool off. He claimed he never had a spring fail doing it this way ( springs probably reached around 650F). He was taught this trick by an illiterate blacksmith.( Bill said, " He couldn't read books, but he sure could read steel !")

By relying on the flash point of kerosene to be his guide to temperature, he had a fairly accurate spring temper ( kept accurate by never varying the circumstances that the temper was done under.)

Stacy
 
I'll probably try the oven first since that is the most controllable method I have. I'm keeping the others filed away for future reference though.

Thanks again.
SDS
 
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