[TheForge] Castable Refractory

[Jerry Frost]

Hi Norm:

Roger Olsen's forge works quite well, he kindly let me play in his smithy a
few years ago while I was in the area.

I built a forge similar to what you're describing a few years ago though
used a different refractory. As Roger suggests I used sono tubes to form the
hard refractory inner liner. I hit the local Home Depot, borrowed a tape
measure (why pack one along eh?) and started comparing tube ODs and IDs till
I found a pair with a .75" annulus (gap).

I tacked the tubes in alignment on a piece of plywood and rammed the
refractory in place with a piece of 3/4" sq. stock and cured it with a 75w
lightbulb for a couple days. Add only enough water to make it workable, in
this case "castable" is entirely different from "pourable". Excess water can
make it shrink check (crack like a dry lake bed) when it dries. The drier
you can work it the better. After it was cured I used an old hole saw to
make the burner port.

I then wrapped the inner liner with 1" 8oz. Kaowool and stuffed it in a
piece of 10 1/2" steel pipe and capped the ends with 14 ga. sheet steel.
There is no exposed Kaowool to breath and it heats up plenty fast though not
as fast as straight Kaowool. On the up side it's concrete tough at a high
yellow heat and doesn't even notice molten borax or other fluxes.

The one thing I would've done differently (in a fundamental way) is use
heavy gage stove pipe for the shell instead of 1/4" wall steel pipe. The
forge doesn't need that much strength, the combination of a hard inner liner
and a stove pipe shell is well more than enough. The major reasons for a
shell are: 1) something to mount fittings, feet, etc. to and 2) contain the
Kaowool. Stove pipe is plenty and it's lots lighter. SS stove pipe would
look cool too. <grin>

Frosty
------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.