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electric/reduction

updated mon 10 apr 00

 

mel jacobson on sat 8 apr 00

Dear Chris and others,

Thank you for your interest in this project.

As to predictions of time or life of coils covered
with ceramic coatings, I think the jury is still out
on that. But, saying that, we are going for 200.

From our experience with the salt kiln at Hay Creek,
it has been rather amazing results. That kiln has
received more damage from mice in the last two years
than from salt. We will use a paint brush and paint some
itc 100 on some bad places...take 10 minutes, and ready
to go again.

A really good test of the itc213 will be Karen Terpstra's new
wood fired kiln and the University of Wisconsin, La Crosse.
I was down for a one day teach in, and She is going to put
truck axles in the fire box....I suggested that she coat them
with itc 213 and see if she can keep them from slumping.
Now, that will be a real test. She will have to clean them well,
sand them, clean with Clorox, then rub the itc 213 on them.
She is very eager to add this element to her new two chamber
kiln. (very nice, well built kiln that she has constructed..of course she
would have been done two months ago had she used flat tops.)
The kiln has some very complex arches, and had to be done
several times...but, She has it complete now.

Rick Mahaffey has reminded me about the many electric reduction
kilns in japan that have been firing for years...And yes, I have seen
them. The coils in those coffin shaped kilns are about a quarter inch
thick, and strung on the surface of the brick. They also get changed
on regular intervals....and remember, the product from most of those
kilns are worth a great deal of money. The coils are cheap compared
to the product gained.

What we are talking about is a major change in how many North
American home potters will approach the electric kiln. It has the
potential of being a complete tool, cone 10, 6, bisque, oxidize and
reduction. (With proper Venting Venting Venting.)

Most professional potters will find this redundant. Perhaps I would
find it useful to fire a small load if time was an issue, or a special
order, but this kiln will never replace my 40 cubic foot flat top
gas fired kiln. (Of course i will never have to change coils in
my 25 year old kiln that someone threw away and I repaired
and sprayed with itc and use only for bisque.)

The first kilns of this kind where designed by Nils for a Woman
that made extreme miniature pots. The small Aim test kiln
became her cone 10 reduction kiln. Other experiments are moving
forward now using a variety of size electric kilns. That is why
I felt the need to build one...See for myself. Bill Jones (PMI)has encoureaged
me to set up a scheme, step by step, that others may follow.
He is going to give it a try too. (Bill is a potter, Ohio State)

I am encouraged that others will explore this idea. It is not
hard to do. The major things that Nils has discovered is:
1. Clean metal, grease free.
2. Use household bleach to clean the surface.
3. Keep the coating thin and consistent.
4. Let them dry well and replace carefully. (new coils would be the
recommendation.) Make clean tight connection to electrical wires.
5. Spay carefully, not filling the grooves, but covering the coils
with itc 100.
6. Final coat with 296A.
7. Feriz Delkic has suggested if the kiln has sections
to cut a small 45 degree angle cut where the sections join.
Pack in a gasket of kaowool soaked in itc100. This will seal
that joint and not allow heat to escape from the rings. If the
rings must be taken apart, the gasket will just come out.

Well, again, exciting times. Things to do, and many steps
forward. It is amazing how clayart gets the word to every
corner of the world in hours.

Mel/MN









minnetonka, minnesota, u.s.a
http://www.pclink.com/melpots (website)

Jim Brooks on sun 9 apr 00

Mel... have been reading your comments about electric reduction with great
interest! This last epistle has me a bit more curious. Why, WHY!, do you use
bleach to clean kiln parts? It is very corrosive, kills lots of germs,
bleaches or lightens in color, sanitizes, but why in a kiln? Doesn't a
firing do most of these things? Thanks Jim...