Cheryl Hoffman on tue 22 oct 02
Hey All,
Thanks for the reassurance that putting the tank in water is OK to do.
I know that the tank that I was using was too small...from the BBQ grill.
I'll have the bigger tank for the next firing. A free thirty gallon (or is
that pounds?)
Now, as far as results...Man, I didn't know a pot could look that bad!
Some of them should be entered in some kind of ugly contest. They'd win for
sure! We had a couple of pieces glazed in turquoise that we were very happy
with...bright color, nice crackle. And then we did three different white
crackle glazes. A Tom Coleman, a fatty white, and a third we call F.U. I
accidentally combined the two containers of Coleman & fatty white and decided
to try it anyway...so you figure out what the F.U. stands for. The fatty
white glaze bubbled up like an overcooked marshmallow and then deflated and
crumbled off when cooled. The Coleman glaze chipped off big chunks, some
during the firing, some when washing them off. The F.U. glaze just looked
like a dirty burnt pot from some old dump. We got one nice white crackle
pot, but can't figure out why that one came out OK as compared to the rest.
I'm using a two burner manifold on an old stripped kiln. The
directions for the burner say to start with the PSI at 1.5 for 5 minutes,
then take it up to 5 PSI. For the first load I kept the PSI at 1.5 the whole
time, 45 minutes (forgot to turn it up). Those were the turquoise and were
fine. The second load, I turned it up to 3 PSI and I had flames touching the
lid. This is also the point where the glazes started to act like a
marshmallow roast. Third load we kept it at 1.5 for an hour but the glazes
did not mature...dull & dirty looking. Fourth load was turquoise again, kept
it at 1.5 and they came out OK but underfired. I can't imagine taking it up
to 5 PSI.
So, as I see it, as far as amount of propane to use, I have 4
controls: valve at the tank, the valve at the regulator, adjusting the pilot,
adjusting the valve to the burners. How far should these valves be open, as
I'm sure that's where the problem is. What pressure do most of you use?
Valve at the tank full open? Valve at the burner full open? We played with
that damn kiln all day and could not seem to reach the proper balance of gas,
air, pressure.
Any sage advice? And how do you access the archives now...guess I
didn't read the posts on that thread.
Cher Hoffman, tired, no wiser but more experienced. Also broke my toe today
while jumping in the pool to cool off...figures, been one of those days.
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