Very cool video. Japanese Hammer making.

[woodchucker]

I have a few questions if you watch this.
My first is are they using coal for heat treating?
When they quench the hammer, they seem to be tempering at the same time, by controlling how fast areas cool. Am I correct about this?

My love of watching Japanese woodworkers, and my respect is quite high. I find them to be at a master class, the way they do things.

 

[benmychree]

It would seem so, it is not coal per se, but coal that has been coked, that is coal that has had the volatile matter cooked out of it leaving nearly pure carbon to burn and create heat, the volatile matter generally contains sulfur and other elements that would contaminate the steel. Blacksmiths usually start with coal and coke it while working the fire before raking it into the center of the fire where the heating is done.

 

[woodchucker]

Thanks, what about the quenching, if you watched it completely, did you understand what he was doing? Was it controlling a temper on the original quench?

 

[benmychree]

Yes, I think that is what he was doing.

 

[markba633csi]

Very Zen

 

[Janderso]

Very interesting.
The process of applying the tool steel on the faces seems pretty straightforward.
I assume the powder was flux of some sort?
That’s a fusion weld correct?
The square piece of steel seemed to stick to the flux when he jammed it into the coals.

Thanks for sharing. Very cool.

 

[woodchucker]

Very interesting.
The process of applying the tool steel on the faces seems pretty straightforward.
I assume the powder was flux of some sort?
That’s a fusion weld correct?
The square piece of steel seemed to stick to the flux when he jammed it into the coals.

Thanks for sharing. Very cool.

Jeff, that's what I assumed, and I don't know how that face stuck so easily before it was even really weld forged on...

and Mark, it was very Zen, very relaxing .. no rushing, just a calm working.. The only thing was the back breaking position that he was in, I imagine my back would give out working leaned over like that.

 

[Manual Mac]

Thanks for this.
I really enjoyed it.

 

[RJSakowski]

Very interesting.
The process of applying the tool steel on the faces seems pretty straightforward.
I assume the powder was flux of some sort?
That’s a fusion weld correct?
The square piece of steel seemed to stick to the flux when he jammed it into the coals.

Thanks for sharing. Very cool.

The process is called forge welding. His particular method is an interesting approach. Usually, the two pieces are heated separately, flux is applied, and the two parts are quickly hammer welded before they cool below a welding heat. I have never seen flux used to hold two parts together while heating. It would certainly simplify to process. I once welded a steel face to a 19th century anvil body. I got the two faces as close to flat as I could abd then welded the perimeter of the weld area, the purpose of which was to exclude any air preventing oxidation, Flux does much the same job by dissolving any oxides that form. During the welding process the flux is squeezed to the outside of the weld, leaving bare metal in close contact.

I'll have to do some research on the composition of that flux. Borax is a commonly used flux. There are some commercial formulations which may have similar properties.

Performing the hardening and tempering in the same step was also new to me. I expect that it worked because hammer faces are generally not that hard. It might be a problem if you were trying to harden to 60 Rc or more.

 

[Ulma Doctor]

I was youtube surfin’ over the weekend, when I first saw this video.
It amazes me, the skill of the blacksmith.