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castable in use

updated sat 27 nov 04

 

Kurt Wild on fri 26 nov 04


I would urge anyone thinking about using a castable to seriously consider a
commercial product over a "home-made" castable., Years ago a student and I
made a small catenary kiln with a "homemade castable":. It did not last
more than a couple years - the stress from firing and the varied weather
conditions here in Wisconsin took its toll on the kiln developing cracks
and a general break down of the castable itself. Based on that I suggest a
commercial castable, it will be worth the money in the long run. For a
short life, limited use, experimental kiln a home-made castable might work
out just fine.

I agree with Hank Morrow - tell your supplier exactly what you want to do
and ask for their recommendation, then follow the instructions for mixing
and curing (firing) to "the letter". I also recommend renting or
borrowing a cement mixer to do the mixing.

The castable that Mel referred to in an earlier posting and which I used on
our little train kiln was A.P. Green, Kastolite 25. Purchased from
Smith-Sharpe Fire Brick Supply in Minneapolis, phone 866-545-6743. The
cast slabs over the ware chamber and Bourry box were 3" thick by 18" wide
and 36" long (across the ware chamber). I never actually weighed the slabs
but calculated them to be 101.25 lbs apiece - definitely taking two people
to move them. They have held up "like new" since made in 1999 under roughly
9 wood firings.

I don't know about casting grates. We used angle iron with ribar welded
inside the angle iron and then positioned them in an upside down V (or tent
like) position.

Kurt