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was color chart, now squirting water into kilns

updated mon 11 jul 05


Vince Pitelka on sat 9 jul 05

> As soon as I chip out all the melted glaze and put new elements into my
> kiln following Tony's advice and as soon as i fix the crackin on the
> bottom, I will try your water canon trick to see the cones on my next
> glaze firing. Should I go ahead and use a little muriatic acid in the
> canon water to help with viewing?
> Oh yeah I almost forgot. Shirt, on or off?

Mel and Taylor -
I know that this is just harmless joking, but now I'm getting worried. I
mean, there ARE novices out there that might not realize that you are
joking. Yeah, okay, you could say "Come on, Vince, is there actually anyone
out there dumb enough to think it is okay to direct a water hose into the
spy hole on a kiln?" and the answer is, yes, there are. Actually "dumb" is
not the right word. But there are people who are so blind to the most
elementary physics, and might actually think that a quick squirt of water
might make the cones visible, when in fact it might send a superheated blast
of steam back in your face that could permanently disfigure and blind you.

I am sometimes amazed at the lack of understand of the most basic physical
principles. I have had students glaze the bottom of pots, and then paint a
layer of wax resist over the glaze, thinking that this would prevent the pot
from sticking to the kiln shelf. Those are the same people who might squirt
water into the kiln in order to see the cones.

Water injection is a valid technique used for other reasons, but it must be
done in particular ways with the right equipment.

This is another of those situations wher Mr. Murphy is just looking for
opportunities to impose his law. Steam explosions can be deadly.
- Vince

Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111,

John Baymore on sun 10 jul 05


Way back in the "ancient history of clay"....... early 70's.......... I
was the full time ceramics technician at Massart in Boston. We had a salt
kiln out in the kiln building behind the main school building located on
Longwood Avenue, right between Beth Isreal and Children's hospitals.

(Yes... a salt kiln right in downtown Boston.........and eventually I put
in a 3 chamber woodfired noborigama there too But I digress.)

Anyway... on one particular rainy night some students were salting the 60-
70 cubic foot kiln at about cone 10. Of course with the rain and high
humidity... that white vapor cloud was VERY evident and hanging near the
ground in the parking lot. So some good samaritan, thinking they were
helping, called the Boston Fire Dept.

Making the long story of a pretty heated discusssion short........

I had to almost "get physical" to prevent a fulltime professional Boston
firemen from sticking the nozzle of a fire hose into the spyport of the
salt kiln at cone 10 and blowing all of us standing right there into
oblivion. The physical science demonstration that would happen when a
small amount of water became a LARGE amount of superheated steam in a
fixed enclosed space seemed to not penetrate his brain very well. I think
he realized I was serious when he moved to do it....... and I yelled at
the students there to RUN fast...and we took off for the kiln room door
full tilt . Luckily he stopped.

It took a supervisor showing up and me having a calm discussion with him
to these guys to realize that all was actually OK... and they let us
continue the firing.

Anyway......... vaguely related to the topic here . Hope your leg
progresses a bit faster for you.



John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA

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