Mig Welding Spring Steel and Heat Treatments ?

[SReynolds]

Made a spring fuller from used car coil spring. It has been annealed. I can now cut it with a hack-saw.

 

I'd very much like to mig weld a hardie shank to the bottom of this spring fuller. Is there a process to use in order to perform this? I don't have a stick welder w/fancy welding rods. 

 

The other thing; I'm thinking I **may** need to harden this fuller and temper it. If so should I harden the entire spring fuller and temper or only a portion of it? If tempering isn't required, possibly harden it just a slight amount like slowly cooling it in hot oil or air cooling? 

 

I can quench this spring steel in water and afterward it is glass hard and shaters when struck w/a hammer. When it was in it's ORIGINAL spring state.....I could cut it with a hacksaw, easily. 

 

I have found that automotive springs, when they are springs, are quite soft. Same is true for heavy/over the road truck flat spring.I can drill them with a drill press and cut them w/a hacksaw.

 

Thusly, my fear is destroying this fuller, by stricking it with a hammer, if not hardened in some form. 

[ThomasPowers]

preheat, weld, then go directly to heating in the forge and normalizing it.

 

I have a swing arm fuller that uses a piece of coil spring as an arm and I use it normalized.  I do replace the arm every 5-8 years depending on how heavy of use it gets.  Maintenance is not a bad thing.

[Crazy Ivan]

I agree with Thomas. Preheat (look up proper temps but likely between 300-500 degrees F), weld, post heat or as Thomas suggests go straight to the forge and normalize. All of my struck tools are left normalized (which is technically heat treating).

[forgemaster]

I'd preheat to greasy stick temperature, (if you search the forums for greasy stick you'll find more info on this).  As otherwise suggested normalise immediately after welding before it has a chance to cool down.