[TheForge] charcoal firepots

Mon Jul 8 09:45:01 2002

I suspect that you're actually reaching a higher temperature (on a regular
basis) in the brake drum forge, and consequently reaching the fusing
temperature of your coal.
At the fusing temperature, the clinker will form into a larger single mass,
whereas below the fusing temperature it won't.
I'm assuming you're using the same coal in both forges, of course.
I've also heard it said that the amount of clinker is proportional to the
amount of air you feed the fire, but, if true, I've always attributed that to
the proportional relationship of air input to fire temperature.

The reason your fire may be going out quicker in the brake drum forge is due to
several factors, but it sounds to me this particular case like this may not be
a fair comparison.
Have you ever built a new clean fire in the brake drum forge, just fired as was
done in the rivet forge, and determined how long the fire lasted?
Have you taken used the rivet forge in a manner similar to what you did in the
brake drum forge (length of forging session, typical amount of forge welding,
etc)?

If the comparison still holds, then it's possible the rivet forge is still able
to get a little air which keeps the fire going on its own, where your brake
drum forge may have been more airtight.

There are many factors involved in fire management (such as the type of fuel,
the type of firepot, type of blast, type and size of forge) that make it very
hard for anyone to make any absolute statements about what is proper and
correct.
That's why I listen to, but rarely follow, the friendly advice from others
about the "right way" to tend a fire.
One has to know enough about the variables involved to try different things and
figure out for themselves what works better for their particular circumstances.

I might mention that I had some coal once that had a very high fusing
temperature. I was anxious to give it a try, thinking a higher fusing
temperature, the less clinker.
That is, until I came to realize that the higher fusing temperature meant
instead of getting a single mass of clinker which I could pull out all at once,
the result was many small pieces of clinker I had to fish out individually. I'd
actually have to pull the fire apart completely, let it cool, separate the
clinker "flakes" from the coke, and start a new fire. Personally, I'll take a
big single mass of clinker over clinker flakes any day.

Bob

-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Rafter Lazy C
Sent: Monday, July 08, 2002 7:52 AM
To: [email protected]
Subject: Re: [TheForge] charcoal firepots

I have recently had a thing driven home to me.  I have a forge that I made
from an old  brake drum and an electric blower with a light dimmer switch
for blower control.  The wind this spring took down my chimney, and I
haven't had time to fix it the way I want, so I keep leaving it alone.  I
also have a rivet forge that I got at an auction.  In my brake drum forge
(my forge) I find that a fire left unattended will go out in about 10 - 15
minutes.  Also, I get huge amounts of clinker in this forge.  In the rivet
forge, I found out yesterday that a fire left unattended for about 2 hours
(with lots of coal and just fired well before leaving it) will still have a
lot of heat to it, and will start right back up when you crank the blower.
Both forges are bottom draft, and I could not believe the difference until I
saw it with my own eyes.  I get almost NO clinker with the rivet forge.  Let
me know what you all think are the reasons for this, please.  I thought that
I built a nice little forge, but after using this rivet forge, I can hardly
figure out what is going on.

Rick Crawford at  Rafter Lazy C
Home of Rick's Forge and Lem the Wonder Mule
email = [email protected]
home page = http://www.tbcnet.com/~rafterlazyc/
near Rochelle, in the middle of northern Illinois, USA