[TheForge] claying a forge

[Jerry Frost]

----- Original Message -----
From: "Peter Fels And Phoebe Palmer" <artgawk@thegrid.net>
To: <theforge@mailman.qth.net>
Sent: Wednesday, December 10, 2003 10:43 PM
Subject: Re: [TheForge] claying a forge


> Jerry: There's some stuff called Permalite ( ground up pearlite) that
> adds some air spaces  in a mix like that for insulation and works quite
> well.....But it is silicosis in a bag and must be used with a
> respirator. It's sold as a concrete additive for light-weight
concrete...PF
>

I use garden pearlite to make insulating refractory but it has a 2,000f
limit so I add a layer of high temp refractory on the fire side. I haven't
tried any from the concrete supplier; smaller particles ought to work better
though.

I use the same basic recipe subbing the pearlite for the sand and use more.
4 pts fireclay to 2-3 pts pearlite to 1/4-1/2 pt portland cement and mix as
before. To avoid the silicosis risk, either wear a mask or wet it first.
Still, silicosis takes either long term or very heavy exposure so it's not
the risk most think. Regardless it pays not to take more chances than
necessary.

You can use quite a bit more water as the pearlite is compressable so the
liner doesn't shrink check on drying. This makes it easier to work with but
it also means you can't ram it as hard and is more fragile. Sawdust works as
well and is how light firebrick is made.

A large campfire, etc. will fire home made firebrick just fine. Fireclay
will fire like any ceramic and even vitrify but vitrification means you got
it WAY too hot. It doesn't like getting that hot and starts degrading
quickly.

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

Meadow Lakes, AK.