|
Posted by spaco on February 9, 2008, 9:30 am
Please log in for more thread options You are dead right about not throwing water on a hot forge.
As another poster said, not all coal is "blacksmithing coal". Some
kinds of coal don't coke up much or at all. Others have a much lower
btu content than we want. I have seen some (in Europe) that were so
oily that flames shot 5 to 10 feet in the air above the forge!
Cleaning the forge and managing the fire:
The clinker (melted ash) will almost always drift towards the bottom of
the firepot. It got there because the fire is so hot that as the ash
forms, it melts into a sticky, glassy glob, sticks to its neighbor piece
of ash/clinker, and is then heavier than anything else in the fire
except your workpiece. So, if you don't find it there in the morning,
it's because somebody moved it!
The firepot in my main forge is about 4 inches deep. Here's how I put
that one out:
When I put my fire out, I first pull the coal to one side of the
hearth, Then I begin to pull the coke to another corner, just skimming
it off the top of what's left of the fire. This leaves about 2 or 3
2/2" of "stuff" left in the bottom. I let this go out by itself.
Many forges will go out by themselves anyway, but mine has a very good
draft, so it will comsume all the coal and coke, so that's why I have to
"tear it down".
Now, the next morning, all that's in the bottom of the firepot is
either clinker, unconsolidated clinker (ash) or coke.
The clinker is usually stuck together in a glassy mass, sometimes in
small pieces, sometimes in a large "doughnut". We often have clinker
contests at the school to see who can extract the largest clinker from
their forge!
During your management of the fire, you should never be "stirring" it.
If you do, you may be mixing coal, coke and clinker together during the
day and this will sure make it harder to separate later.
As you know, the forge works by blowing air through glowing coke to
make hot gases which heat the work. This process consumes the coke.
The heat from the glowing coke heats the coal that surrounds it and
evaporates the volatile matter in the coal so it becomes coke.
Okay, so as you blow the fire, the coke burns away and you have to
replace it with freshly make coke. To do this, you gently push freshly
made coke from the edge of the fire INTO the center of the fire so it is
in a position to intercept the air blast. Then you refill the spot left
by the coke with fresh coal. Repeat, repeat, repeat.
So, you see, any clinker that has formed HAS to form from the
dissapearing coke, which dissapeared from the center of the fire. That
means that ALL the clinker HAS to form where the coke dissapeared from,
which is the bottom center of the firepot.
During the day, one must clean the fire, removing at least a portion
of the clinker. If you don't, the clinker will take up the room at the
bottom of the firepot where the coke is supposed to go, If this is the
case, the clinker will be down there, glowing, but not producing any
heat for you. What's worse is that oxygen int the incoming air blast
won't be used up on its way to heat your work and your work will oxide
much faster.
Hope this helps.
Go to ABAANA.org and look for the affiliate closest to you in the New
York area for classes. Most ABANA (Artist Blacksmith Association of
North America) "chapters" have meetings where folks get together to
"beat on iron" and they always welcome a serious newcomer, which you
seem to be. All you need to do is to attend a meeting ask the
questions and all will become clear.
Many of these clubs offer classes. Any of them can also direct you to
craft schools where blacksmithing is taught. You are in one of the best
parts of the country for craft schools of this sort. I don't mean to
choose one school over another, but the John C. Campbell school in
Brasstown NC has a lot to offer in the way of blacksmithing. Take a
look: > http://www.folkschool.org/
If you have any other questions or "yah-buts", feel free to post them
here or email off group,
Pete Stanaitis
------------------------------------------------------
Mountain King wrote:
> Hey, I'm a brand spankin' new smith who's having a bit of a problem.
> I've fired my forge twice now since I've built it, and it makes me
> happier than anything I've ever seen, but I'm afraid that I'm really
> no good at using it. I've been reading everything I can, and I can
> get a *decent* fire going which gets my iron up to yellow, now and
> then (but that's something I can improve on my own, I think) The
> problem comes in two places: Putting the fire out, and starting it
> again the next day.
>
> Fire out-
> What's the best way? I've read that you shouldn't just throw water on
> the thing since that could crack the firepot / tuyere. One thing I
> read recommended that I shovel the whole fire into a water-filled
> bucket. I guess that works fine for making sure it's out, but how
> easy is it to re-use that coke the next day?
>
> And up again-
> Okay guys, this is a little embarrassing but... how do you tell coke
> from clinkers? Either my fire isn't producing clinkers (miraculous!),
> or I'm a little clueless. All of my sources just tell me "separate
> the coke from the clinkers, using the coke for yaddah yaddah yaddah".
> I can tell coal from not-coal just fine, but beyond that I can only
> make an educated guess. Please, in as much detail as you can,
> describe a piece of coke as opposed to a clinker.
>
> One other question- Does anybody know of any classes on Smithing of
> any sort being offered around New York?
>
> Thanks a lot for any insight you can give.
| 
XML site map