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first pit firing and not alone any more

updated mon 15 apr 02


Martin Rice on sun 14 apr 02

Hi, All:

Well, I finally did my very first ever firing. Not in my new kiln that I =
had built in San Jos=E9 because the shelves are still not here yet, but =
in a pit. Dug a pit 75 cm square and 1 meter deep. I've been collecting =
sawdust and shavings for months now from a carpenter's shop in the area. =
The sawdust I used for this firing is mostly -- perhaps all, not sure -- =
cedar. However I don't know what kind. Certainly not the fragrant =
variety that are used in chests and closets. It is not very heavy/dense. =
The shavings are quite small and they were all mixed together.

I put about 10 cm in the bottom of the pit, put four pots, filled with =
sawdust on that, put another 15 cm or so over them, and four more pots =
on that. Then filled the hole to about 75 cm. Ignited the sawdust and =
then when it seemed to be smoldering well, covered the pit with a sheet =
of corregated tin roofing material.

It burned and cooled for 30 hours.

The seven pieces I put in were all very small cylinders (none higher =
than 4 inches, none wider than three) made from my red earthenware clay, =
which I finally now know is completely natural, just dug out of the =
ground and cleaned up but nothing added. It's supposed to be cone 06. =
With my being kilnless, of course the pieces were not bisqued, but they =
were bone dry, and from everything I've read here, I expected a lot of =
breakage. And that's what happened

The results: 5 pieces with cracks (but none fell apart or exploded), 2 =
without any cracks. None of the pieces were burnished because I never =
thought to do it when they were at the right stage and didn't learn from =
Snail that it could be done at bone dry until about an hour afer the =
pieces were already in the pit. Color: a truly deep, deep black that I =
really like.

An interesting sidelight. I don't know if this was cause and effect or =
not, but the two unbroken pieces were two of three that I had sanded =
with a very fine grit (there were three of these out of the seven).

Of course I have absolutely no idea what the temperature was in the pit.

Because I have what seems as an infinite supply of these little pots =
that I've thrown while teaching myself and have saved to practice =
glazing and firing, I have plenty left to try again. My next firing will =
be with sawdust that's much finer and denser (same size bags that I used =
this time weigh about 3 times as much). I also have a large supply of =
dried horse manure (my wife has two horses) and I'll put some of that in =
as well. But the next batch will also be burnished.

Meanwhile, I'm not going to be the lone jungle potter out here much =
longer. I met a man, Gerrado Selva, in San Isidro, the market town about =
an hour from here where we do our shopping, who is a very experienced =
potter. He has opened a little shop there about a month ago. He's a =
Costa Rican citizen who has a degree in fine arts from England and an =
MFA with a focus on glass blowing from Rochester in the US. He's also a =
playwright and musician. His day job is teaching art at the local high =

I immediately asked him if he could give me lessons. He said that he =
didn't really have time to teach one student, but that he'd like to give =
classes to a small group of four or five to help him make ends meet =
while his store is getting established. So I talked to some of my =
friends who live in my area and it turns out that three of them, who =
have never thrown a pot, had always wanted to try it. Now we have a =
class of four and had our first lesson yesterday. We're meeting two =
hours every Saturday morning.

Gerrado has been doing this for over 20 years and thus is a great source =
of information for me. Also, now with a group of 4, there will be people =
going to the States for visits a few times a year and we'll be able to =
get supplies there that the visitors will bring back for the group.

Things are looking up in the jungle!

Lagunas de Bar=FA, Costa Rica
Revised and updated 4/1/02