2 fails heat treating crow bar

[Blood Groove]

I'm in a blacksmithing apprenticeship and I'm trying to make a knife from a crow bar. My idea is to have a super sturdy knife that has the pry head of a crow bar on the butt of the knife. That would make it good for prying (which knives are usually used for but don't axcel at). Anyway I've tried twice to make one, and both knives have cracked in heat treating. DOes anyone know what type of steel crow bars are made out of (I was using a craftsman) and if so how to heat treat them? We were using a salt water solution, would oil have been better? Any info will help, thanks
-Blood Groove

[Rob Browne]

Generally with unknown steel I would do a warm oil quench first, if that does not work then cold oil, then water, then brine, then cold brine. Its probably an oil quenching steel. Crowbars need to be really strong and a bit springy to do their job. Knock up a quick test blade out of a bit of scrap then try a warm oil quench as a test then follow the sequence if it does not harden the steel.

This would be SOP with unknown steels.

[Nakedanvil - Grant Sarver]

rmcpb: While I agree with your methodology 100%, I would add a caution that warm oil is usually considered to be a bit faster than cold oil due to cold oil being "sluggish" or less fluid. But of course "warm" and "cold" are very subjective terms. You certainly want to work your way down the scale and not start off with salt solution. Many beginers often make the mistake of getting the steel way too hot. As it is probably a simple carbon steel, you want to quench it from right about where it will no longer attract a magnet.

[Mike Ameling]

It also depends upon how GOOD of a knife edge you want. Too many people want/expect to sharpen a knife today, use it hard, and still retain a razor edge a year from next Tuesday! Totally unrealistic expectations. The softer the cutting edge is, the more often you have to touch up the edge to sharpen it. With a "working knife", you touch up the edge most every time you use it. That way you know how the edge is. And it is much easier to maintain. (Try re-sharpening a Buck knife!)

Yes, it sounds like the quench was way too quick. But if you really want to use the handle on that knife as a pry bar, consider just letting it air-cool. Let the quality of the steel itself work in that pry bar function. Plus the "soft" knife edge will need more frequent attention.

When you try to modify an existing tool to a new function, you will often run into problems with the original material. It was designed and heat-treated for the original purpose. Changing that purpose can get ... tricky.

And COMBO tools are always a problem. Very often the different parts need to be heat-treated differently. And you end up with "shear lines" within the steel itself where the steel transitions from one heat-treat to another. In the end, you are better off getting two separate tools designed for their specific tasks.

Just a few humble thoughts to share. Take them as such.

Mikey - that grumpy ol' German blacksmith out in the Hinterlands

[ThomasPowers]

Funny I had a student make a blade from a crowbar. Part of the project was to forge out the nail puller end into another blade like shape for testing of heat treat options. Vegetable oil was a bit soft so we went to brine and it hardened nicely---so much so that we have 2 knives, though the end one looks like a fish with the puller the tail.

Test your steel BEFORE you waste all that forge time! (And note that the steel used in a craftsman crow bar could be changed at will by the company, no guarantee that any two of them will be the same alloy!)

[Charlotte]

Years ago one of my Uncles, worked for a small manufacturer that did contract work for Sears. Every year they would have to bid for a contract to manufactur goods under Sears brand names.

In general the actual company making any thing for Sears is subject to change year to year.

Other brand names may or may not be made in a "home" factory. Another example comes to mind.:
I was in a junk yard in East Tennesse, when I came on a pile of scrap wrenches. They were very appearently forging rejects. The name on the side was S K Wayne , a brand of mechanics tools sold in Autoparts stores. The worker there said that they came from a local forge and that he could not let me pick up any of the scrap.

[Dragons lair]

Really got to watch some of sears stuff. About 20yrs ago I needed a 3/4 in breaker bar
and large socket. Tool crib where I was working had just bought a set. After a hard battlethe head guy said if you damage it you will have to replace it. Went home removed the crankshaft bolt. Went to wipe the tools down. Trere in large stamped letters was Craftsman Made in Tiawan. Shop head took off to sears and returned them.
Brands just don't matter.
Ken