japanese forge

[Wayne]

After watching the video of the guy making scissors I have watched several others. In one a knife is being forged but it is the hearth that interests me.
The hearth was rectangular in section and fully enclosed with an entrance at one end, set on the top was a low cicular metal ring with a circular wooden lid to close it.( low chimney)?
Does anyone have any experience of these or know of the reason for this design?
My interest is in the the idea that this type of hearth is very similar to the enclosed hearths shaped like a house that appear in various Roman illustrations.

[ThomasPowers]

You moght look over some of the neo-tribal forges as I recall one with a closed top made from adobe used by a smith part of that group. He said it used less fuel.

as I recall.

[Francis Trez Cole]

nova did a documentry on the samuri sword you can see in great detail the forge and how it works. The fire pot is narrow and long you would use more wood charcoal then coal The book The craft of the Japanese sword ISBN#0-87011=798-x is close to the whole nova program. There is a detailed layout of the forge and box bellows

[Wayne]

Thanks for the info guys, I have been looking a lot more on you tube especially at the blacksmiths from India and the Nepal region. The set ups they have and the tools being used - stone anvils etc are providing a lot of fuel for thought.

[Conrad Hodson]

Thanks for the info guys, I have been looking a lot more on you tube especially at the blacksmiths from India and the Nepal region. The set ups they have and the tools being used - stone anvils etc are providing a lot of fuel for thought.

Do they show how often they change anvils? I have some experience working on stone anvils (we were demoing an early medieval smithy) and we found that pieces broke off of them regularly. We were using basalt, (the strongest stone available locally) starting in the 100-150 pound range, set into a stump with a big V-notch to accomodate the irregular shapes of the stones. Most work was with a 2 1/2 pound hammer.

Problem seemed to be that any time you set a stone up with a flat face uppermost to pound on, you are pounding on what a flintknapper would call a "platform". To them this is desirable, because they want to pop flakes off and that is the way to do it. Well, the "flakes" off the anvil weighed 10-30 pounds each, and just like a flint flake the edge at the bottom of the split was sharp. You had to be alert all the time, to twitch your foot aside because that's right where it headed, and it gave the impression that a heavy boot wouldn't even slow it down.

A lesser problem was the way the surface powdered away and roughened as you hammered. In period, smiths had little stake anvils or simple smooth metal blocks on another stump; they could take a final heat to smooth up workpieces that needed it, and probably just left it rough where it didn't matter.

It's possible people in other areas have stronger stones available, though I know that Icelanders and others got by with basalt. Certainly any smith who works at ground level like Africans and a lot of Asians do, wouldn't worry about big falling flakes--you could just bury the anvil stone a little, or bind the bottom with rope or withes, so that flakes could separate in a controlled way.

If you get a chance to check out any actual users of stone anvils, make sure to find out what sort of stone they prefer to use! And it still wouldn't surprise me to find their smithy at the base of a rockslide, just because fuel, iron stock and even customers are more mobile than great big rocks, and I suspect regular replacement will be needed. I know we found gathering new anvil material to be hard and somewhat dangerous, and we had modern motor vehicles to haul with!

Conrad Hodson

[ThomasPowers]

Conrad; were you working with real wrought iron and so at white heat? It's a lot softer than modern mild steel when it's up to that temp and you don't need to pound as much!

Of course as a geologist I wouldn't consider basalt very hard---I like the description of the asian anvils made from Jade which should resist cracking a lot more than basalt does.

(BTW was it a vesicular basalt? I've been meaning to pick up a chunk to refine blooms on but the "good stuff" I've so far found here was on tribal land.)

[Wayne]

Reading through 'Iron in Archaeology' there are descriptions of various excavated sites where stone anvils have been found but only a couple mention that the stones were limestone - one being Trapazoidal in shape. I suppose that if the material is cheap/free and easily replaceable then if it breaks -so what?

[ThomasPowers]

If it's for a bloomery soft is not so much an issue---we have consolidated juicy blooms with a wooden hammer before!

[Frosty]

Basalt isn't a great choice for an anvil, it's pretty coarse grained and brittle. I doubt the flat made much af a knapping platform, basalt sucks as a knapping stone.

Look for as fine a grained stone as you can, marble is a lot harder than most folk think and it's got a little give that makes it stand up to hammering if the iron is good and hot.

The stone anvils that worked best for me were untra mafic stone, probably, hornblend or similar. You can hardly scratch em with a dozer or excavator. They're very fine grained almost glassy looking on weathered surfaces. Broken surfaces are very smooth almost like plaster in texture.

Smooth granite is okay though not great. Gneiss is larger grained but stands up better than granite but it's a metamorphic so it's got a refined grain, basically it's been heat treated.

Final refinement of the iron work if necessary would've been done with files and stones.

Frosty the Lucky.