Hammer quenching...?

[GNJC]

I've just been trawling the web during a free half hour and came across this video of a Japanese bladesmith.

 

[Dogsoldat]

I'm sure someone else will chime in,  but being a Japanese bladesmith  I suspect he's working with a wet hammer and anvil to blow the scale off the piece he is forging. 

[GNJC]

Thanks for that Dogsoldat. It's pure ignorance on my part then; I have never heard of that technique before. Looking at the video again I see that the anvil is wet, but I can't say that I see any scale flying off or that the metal looks any cleaner than would otherwise be the case. Is this just an Eastern / Japanese thing?

[Crazy Ivan]

From what I gather, bladesmiths sometimes finish a blade on a wet anvil to help coax the slag off the blade during final forging. the wet hammer may help to do that same. This post may have better luck in the bladesmithing section of the forum. Either way I'm sure you will get the right answers regardless. Thats a cool shop set up in the video too!

-Crazy Ivan

[Glenn]

He is using the hammer to transfer water to the anvil face, You can see it again at about 7:12.

[GNJC]

Quite right Glenn, that is the case, I guess any hammer-quenching is a incidental. Nonetheless, it is a new thing for me and I still can't say it looks like there is notably less scale than otherwise. I'll give it go and find out.

[John B]

It is common practice to wet anvil and flatter face before using them in a finishing situation. It gives a clean smooth finish. ensure anvil is clean and also workpiece first though,

[Stephen Olivo]

Wet forging means you have a lot less grinding to do or filing.  I use it on blades often.  I also sometimes use it on other decorative stuff as it makes scale pitting a none issue.  It really is a good technique to use.  

[quint]

I tried this a little, funny a couple of hammer blows sounded like gun shots going off lol. I figured I would probably stop that for a bit as I am sure the neighbors didnt appreciate it. Is this normal or was I using a tad too much water. 

[John B]

Tad too much heat, and place the hot iron on the water before striking.

[Stephen Olivo]

The loud bang is when water hits the hot steel and vaporizes blowing the scale off of the steel.  Its normal to hear it once in a while while forging this way. As you get better at doing this type of forging to keep heat longer especially in small pieces you can bounce the piece off the anvil.  Timing it so that the hammer strikes the hot steel at the moment the steel touches the anvil and then they both come off of the anvil.  Takes some practice but makes working heats noticeably longer.

[rockstar.esq]

I've tried it myself and it makes the scale blow off.  I quit doing it when it occurred to me that dipping my hammer in water was swelling my wooden handle - crushing fibers and resulting in loose hammer heads.  Dipping the water with a ladle solves that issue.

[quint]

Thanks for the insight guys. 

[Stephen Olivo]

I only dip the face in.  Its all that necessary to move the little bit of water necessary to make it work.

[Frank Turley]

Somewhere I heard the term, "washing the blade." The thermal shock helps pop heavy scale off the work. Yataiki* said that if you  repeatedly wash it eight times, it will help to keep the finished blade from rusting. Some Japanese toolsmiths/bladesmiths keep a small whisk by their anvil at all times. It is dipped in water in order to wet the anvil face.

 

*Premier sawsmith and toolsmith of Japan (RIP)

[Borntoolate]

So after doing this do you clean your anvil up?   And if so how?    

 

I try to keep mine dry.   If a drop of sweat gets on it then the next day it will have a rusty sweat bloom on it.   Assuming this was late in the day.    

 

And of course people are always wanting to put cold sweaty drinks on metal surfaces in the shop.   I try to keep them waxed and in some cases oiled if they only get used occasionally.   Of course constant use is the solution I think.    That pesky day job once again gets in the way!   

[Stephen Olivo]

Most of the time working the hot steel on it dries it off pretty darn quickly.  Otherwise I might grab a rag or my apron but usually I don't even think about it.  Takes all winter for the face of my anvil to get just a tiny little bit of rust on it and that goes away as soon as I am done with one heat.  

[GNJC]

Hmm, my ignorance seems to know no bounds... this method really had gone unnoticed. I'll do some more research and give it a go; I guess practice will be the best thing, if I can get to the point where I remove even half the scale on a given piece I'll be very happy. Thanks for all the information gents.

[Dan P.]

I shared my dynamic and groundbreaking innovation involving this technique on another forum. I call it The MagiAquaForge^TM;

 

http://www.bladesmithsforum.com/index.php?showtopic=27004#entry255331

[Stephen Olivo]

lol fun link to read through.  I hadn't seen that one.  Thanks for sharing

[GNJC]

Good idea Dan, I don't much like the idea of soaking my hammer so I had also worked out a couple of ideas instead: 1) to use mouthfuls / mouths full of water taken during heats and then spat / dribbled out as necessary (I think your method may be more dignified); or 2) to have a soaked sponge - wrapped in a plastic bag but open at the necessary end - on the anvil with a loop of string going over it and down to near the ground, a bit of wood through the loop would allow me to squeeze water out when needed; or the hand holding the work could rest on it and squeeze. In fact, now that my brain has started to work, I think a better method would be to use a flat-sided washing-up-liquid bottle (maybe filled with sponge), this would negate the need for a plug in a can etc.

 

Obviously haven't tried these yet but they seem reasonable.

[Stephen Olivo]

lol feel like over thinking it?  I like the can idea if your going to forge a lot of blades in a row otherwise a can of water like the can your using just sitting near it to dip the face of your hammer in is plenty enough.  You don't need a lot of water just a little.  A plastic nipple on the end of a squeeze bottle would give you more control in the amounts you need without causing a puddle on or around your anvil.  I usually find a face dip rubbed on the anvil all that is required. 

 

OF course there is always the urge to see someone make a complicated machine to do something simple.  but in that case Pictures are required :D

[Chinobi]

Put a pinhole in the lid of a pint water bottle, invert and squeeze as needed :)

Or forge a finishing hammer with a lot of thin vanes on the sides that capture water through capillary action, or has a fullered groove that can act as a trough :p as much as I love speculating on new mechanics there is a strong KISS vibe here :)

[John B]

When tending the coal fuelled hearths there were always four basic tools used, a poker, a rake, a slice/shovel, and a swab.

 

The swab was basically a handle which a held straw bundle that was used to dip into the slack tub, the capilliary action in the straw held the water, this was then distributed around the coal /coke to control fire spread, and also used on the anvil when flattering, or locally to control twists

 

you could probably use a pure bristle brush or rag bundle of appropriate size

[rockstar.esq]

I figured out that if my hammer hand get's wet - I'll get a blister for sure.  The modest advantage of the wet forging wasn't worth it for most heats.  It seems like a stainless steel wire brush could be dipped and used for transferring a modest amount of water without causing too much trouble but still be useful as a wire brush when dry.