hey everyone, Im new to all this just geting started,can yall tell me if most leaf springs are 5160, and also im having troulble geting the steel soft enough to grind and drill, I brought it to nonmagnetic and left it in my forge overnight 3 times, its still very hard. any sugestion?

There are other alloys that are used these days than 5160. Others will have to tell you about them,

5160 should be anneal by bringing to 1450 deg f. and allowed to air cool
However, it must be held at that temperature for a few minutes. Be sure to heat through.

Even fully annealed, with almost 1% Chrominum and almost 1% manganese, it does not respond to cold work gracefully. Please check for the thread "Reflections on drawfiling 5160" by using search.

I have worn out more than one cheap bandsaw blade cutting old truck springs.

Thank you!!

Cobalt drill bits, and grinding, I have had them strip the teeth off files. Didn't know that annealling of these takes a few minutes soak, but that makes sense to soften all the way throught.

Annealing in a box of bucket of wood ashes or hot dry sand will help, of you are in a cold climate.

i reently bought a big bag of vermiulite for anealing ... put it in a 30 gal metal bucket heated my blades to ritical and buried um in it ... seemed to work real well...

The mechanism of annealing is to encourage the carbon to diffuse out of the austenite to form large iron carbides. This leaves the iron with little to no carbon and it gets soft. Diffusion takes time at any temperature but it goes faster at higher temperatures. If you want to anneal 5160, I would suggest you first heat up a larger block of steel and put that in a bucket/box of vermiculite. Then heat up the work piece to a bright red and bury it in the vermiculite and let it slow cool. The slow cooling just adds time for the carbon to diffuse to the carbides.

dont bother trying to cut or drill at all. i'd reccomend just the good old fashiond smashy smashy and a oxy torch cutter. minimize grinding ect at much as possible. i'd reccomend for nice finishes a double cut bastard file going sideways. was taught that by my ac mechanic teach. gives a very flat finish compared to grinders. hand tools ftw. watch out for pits in the metal. it seems to corrode very funny and depending on how old the spring is you'll get a milllion tiny little black holes that are difficult to get out ^^
cheers

I have had a lot of problems with these as well. best thing is just to use a hot cut hardy or an improvised chisel

to anneal " soften " steel you must bring it to critical temp and cool it very slow. hardwood ashes or " oil dry " work well. even dry sand.

For annealing I had a 55 gallon drum that was cut above the bottom rib-about 1/3. I filled it with the gray wood ashes that came out of the wood stove. Before putting a part into them I would stir them to fluff them up some. Toss the piece in and it will take hours to cool down.

I mainly used it for cast iron repairs that I did in my shop.

I anneal by heating the blade to critical, let it soak, and then turn off the blower to my forge. I then compact the ashes together. The next day, the blade is still warm.

I don't know the 'science' behind annealing 5160 but in the past when I tried heating to critical (or slightly beyond) and 'soaking' for a few minutes and then air cooling , it did not soften the steel much. In fact I burnt up a couple of drill bits trying to drill holes in the tang for the pins. Then I tried the 'slow cool' method. I reheated and immediately put the blade in a garbage can full of wood ash. After a day of cooling I was able to not only drill it without damaging the drill bits but was able to shape it with a file (draw filing as well).

I once annealed a file simply by building a large fire and burying the file in the center. Then I kept feeding the fire for hours, until it was so hot I couldn't approach it to add more wood. Then I let it burn itself out and I removed the file the next day. It seems to have worked.

i use lime.... I gotta 5 ga bucket with a lid and filled it with lime...the same stuff you put on your lawn...its like talcum powder....so it is dense and holds temp a long time....works well for me....10 minutes at the forge saves an hr of bench time...if you dont believe that forge a taper point and grind a taper point....sometimes you have to do it a couple of times....check the hardness by seeing if a file skates on it or digs in