Bob Ouellette

Very interesting. Thank you for the information.

Would tempering after straightening effect the stress?

I have a mister set up on my grinder. I'm addition to keeping the heat down, it also keeps the amount of dust in the air down. I also have a catch hooked up to a cyclone dust separator powered by my shop vac. The biggest problem I have is not having a way to direct the runoff water that doesn't make it into the vacuum tubing.

Oh, I didn't measure it, but I'd say I was closer to 0.025-0.035 thick

I just did 3 close to final thickness. They did indeed warp, but the straightening hammer I made worked fantastically.

I think that's a good summary. This was the only one it the 3 that warped again. I tempered a bit softer in my oven and they're all straight still.

@Charles dP I did just find that if your temper isn't even, it will undo the straightening. I straightened a blade tonight and afterwards realized I didn't stamp any of the 3 blades I hardened, so I had to make a spot near the spine dead soft. The warp came back, but it was limited to the edge of the area that was reheated. Here's the warp side by side before and after I fixed it the second time.

Post straightening temper did not affect the straightness.

I got at least 2x 9" chef's knives ground and 2 more to go. I also glued up another knife and finished the bench scraper I forged yesterday. I forged it from 1/4 x 2.5" to 1/16" x 5.5" and it was a colossal pain the whole time, but the variable chamber size of my new forge was real handy. Mild steel with a baked on oil finish and a bubinga handle.

Sure thing. I can actually test that one out right away since it's not handled yet.

Oh, that's absolutely a fair point

What do you have against rain drop pattern? It doesn't seem like more of a pain than anything else.

1. Jaron Martindale 2. Bob Ouellette

I'm also supposed to be having a third foot surgery in about a month, so there's that too.

Great! I'll have to the knife made and set aside in case I run out of motivation lol

I had a piece of end grain wood do something similar to me when I was doing the final fit up. The back half of the handle came off in my hands just holding it.

It does cause plastic deformation, but I don't know that it is significant enough to cause a weak spot. It would be interesting to experiment with it. I'm still having a hard time getting through forging a 9" chef's knife in one go, so maybe once I can I'll forge a pair of test-to-failure knives and purposely put a slight bend in one to straighten after heat treat.

I actually don't know. Thinking about it, it seems like you want to be able to be pretty precise with your strikes. Anything softer doesn't seem like they'd hold up to hitting a hardened blade.

Forge finished knife has been sold.

JJ Simon told me about these a few weeks ago and suggest I make some. They're all 1/4" carbide rods domed and soldered into a tack hammer. They all have a baked-on oil finish. I had my first opportunity to use I've last night. I had a knife warp in the quench more than I could grind out. After the 2 tempering cycles at 350° F, I decided to give it a go. It blew my mind how easy it was to end up with a straight blade. The hammer marks disappeared pretty quick when I was cleaning up the scale from heat treating. I'm disappointed I didn't take a better picture of the warp before I fixed it. You can see all the faint like marks it made as I hammered the inside of the curve. I was even able to fix a bit of a twist.

If you're worried about the diameter of the wheel or the amount of rubber left, you could probably add layers of rubber and have it machined down to the original diameter. I'd use a strip of material half as thick as what you need per side. Apply it with plenty of the appropriate adhesive and lay the strip so that the tail end won't catch as you grind. Similar to the way you'd put Teflon tape on pipe threads. After the adhesive cures, your machinist should be able to true it up.

It's essentially a carbide peen. You hammer the inside of the curve to make it longer and straighten your blade out. I had a blade warp in the quench last night and it blew me away how easy it was to fix.

Alright! My comfort zone is winning! Lol

That looks awesome!

I made these at the suggestion of JJ Simon and they're great for straightening blades post heat treat. Each hammer is 1/4" diameter tungsten domed and soldered into the face of a tack hammer.