O-1 vs W-1

Watching FIF I wondered what happened to the old 2 stage process - harden the piece then "draw the temper" that I was taught 50+ years ago?
Reply to
Clare Snyder
Loading thread data ...
formatting link

They need a large audience to support production costs, not just the handfull discussing heat treating here.
formatting link

Reply to
Jim Wilkins
I assume that this "FIF" is a set of made-for-TV videos? I don't know how sophisticated they are, technically, but it's true that a number of tools, including knives, were traditionally tempered in the same heat as the heat-hardening. The craftsman would partially quench a blade; pull it out of the quench and either file or sand a spot very quickly,so they could see tempering colors; and when the spot reached the color they wanted, quench it again to stop the tempering.
This does not produce the best combination of properties overall, but it can produce a particular combination of properties, distributed to different parts of the piece, that are desired. For example, an edged blade that has to be tough on the back but as hard as possible on the edge.
Something similar is done with quality hammer heads. The whole face is hardened and tempered, and then a ring around the periphery of the face is overtempered, to keep pieces of the hammer face edge from chipping off.
This kind of quick tempering is not nearly as good in terms of general performance as a long soak at tempering termperature -- up to 3 hours or so. The long soak will give you the desired stress relief at a slightly lower temperature, thus maintaining the hardness of the piece. But if hardness isn't what you're after, a quick temper often works.
Reply to
Ed Huntress
they'd put a lot less energy into attempting to create drama & tension and more into teaching the craft, there's enough in there to keep it at least m arginally interesting.
oil. While it gives that satisfying and dramatic plume of flame and smoke, I thought W-1 is supposed to be quenched in water.
t why would they do that?
FIF is "Forged in Fire," a show on the History Channel https://www.history. com/shows/forged-in-fire .
Pick an episode and watch it - there's certainly some metalworking going on there, but... it's lacking in a lot of areas, like the whole heat treating thing we're discussing here (though I did see someone do a selective heat treat by heating part of the blade with an OA torch).
Another thing that they barely give a token nod to is safety. Seriously, I saw a guy holding a small piece of brass (maybe a couple of inches square a nd 1/8 thick) in his bare hands and hold it up to a spinning drill press. D efinitely cringeworthy, and ended up with some blood and bandaids.
If you look past the shouting and the overdramatization, some of these guys are remarkable craftsmen.
Reply to
Thanks. I'll have to take a look.
Oh, I did. Well, I guess you could learn stuff if you watched a lot of it. It reminds me of the car-customizing shows. Sometimes, you learn something.
They do seem to produce some really nice final products. It seems, though, that they just videotape the dramatic parts.
Reply to
Ed Huntress

Site Timeline

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.