Temper tongs ???

[Phil Dwyer]

Hi Folks,

I read about temper tongs in a Nick wheeler thread. Anyone use them?

As I recall, Nick described them as two 4" long pieces of 1" square stock welded onto tongs. They're heated up in the forge to red hot then used along the spine of the blade while the edge is submersed in water.

I get the idea of using them to draw the hardness of the spine back. (The thread was about the making of an ABS test knife, which needs to bend to 90° without breaking through.) As I understand his use of the, he did a full quench on the whole bade and a full tempered of it. Then he drew back the spine further.

What I'm fuzzy on is what the target temp is for the spine to draw it back with the temper tongs, and how you know you've reached it? If the temper tong's bars are only 4" that must mean you have to work them along the blade. Is it done in one heat of the temper tongs? Etc?

Thanks for your input, Phil

 

[Stacy E. Apelt - Bladesmith]

You aren't aiming at a spine hardness ( just more softness) but at only leaving the edge hard. You use the tongs as the heat source to apply heat to the spine. As the spine heats up you do one of two things. Either watch the temper colors run toward the edge ( so-so as far as exactness), or you place the edge in a tray with 1/4" of water to keep the edge from heating up. The second choice is the best and most reliable.

 

[Phil Dwyer]

Thanks Stacy. I understood all that, but still wonder about the actual temp and process....

What I'm fuzzy on is what the target temp is for the spine to draw it back with the temper tongs, and how you know you've reached it? If the temper tong bars are only 4" that must mean you have to work them along the blade [spine 4" at a time]. Is it done in one heat of the temper tongs? Etc?
​

 

[NickWheeler]

Hi Phil


Using temper tongs is just as much of an art as it is a science. Or some crap like that

They are tricky to use... the only advantage over using a torch is it's easier to make sure you don't overheat anything you don't want to get hot.

I clean the blade so that I can see the colors move across the blade. I hold the tongs in place until the colors go just past blue, and start to show a silvery blue color.

Now that I have a temp gun I suppose I could try to figure out what the actual temps are, but I'd need a couple more hands.

Since I made my tong blocks about 4" long, it does take several times (overlapping each) to cover the length of a 10" blade. Once I've gone over the whole blade (so figure several times into the forge and onto the blade with the tongs) then I buff off the oxides and do this to the whole blade at least 3 times.

It's very time consuming, but it paid off for me. However, I am not married to the idea. I think a guy who is skilled with a torch could do it just as well and a LOT faster.

Please keep in mind this is only something I did on practice test blades and my actual test blade. I've never done this to a knife I've sold as I didn't feel it was necessary.

 

[Phil Dwyer]

Thanks Nick! That's kind of what I imagined. You're right it does sound like a lot of work. Kind of cool though. I'm thinking I might just go the thick clay/cement route when quenching to keep the hardness from the spine in the first place.

 

[galadduin]

Thanks Nick! That's kind of what I imagined. You're right it does sound like a lot of work. Kind of cool though. I'm thinking I might just go the thick clay/cement route when quenching to keep the hardness from the spine in the first place.

Phil, the tong or torch is very different from clay treatments. One makes sprinng tempered martensite spine one makes ductile - pearlite spine. One flexes one bends.

If the spine was thin I would prefer to use the tong idea. Thicker spine - like a tanto, the clay treatment would be rational.

Emre