search  current discussion  categories  kilns & firing - misc 

old kiln, what to do???

updated fri 14 nov 03

 

Kit Shannon on wed 12 nov 03


Hi. I've just gotten out of a community studio situation by building my
own studio. I've been making pots part time for about 8 years now, but
i'm on my own now and have a question. I recently acuired a very old,
homemade, electric kiln. It is pretty small, maybe 14 inches wide by 24
inches tall. I didn't really need the kiln because I just bought a
brand new kiln but I couldn't turn down a FREE kiln. The lady I got it
from hadn't made pots for probably 20 years or more. I bought her old
wheel and she gave me lots of glaze materials, magazines, etc. Anyway,
after I had most of the stuff and the kiln loaded into my truck, she
pulls out this big bag of white lead and asks if I want it!!! Of course
I told her no no no, but now I realize I can't really use this kiln to
even bisque in cause it and the shelves and posts probably have lead
contamination. I thought about giving it away, but I don't really trust
someone else to understand it can't be used for functional work...
But what can I do with it...

I've read the archives about lead contamitation a little but I'm still
unsure how to procede with this kiln...

Can I take all the wiring out and convert it into a raku kiln? Or would
the fumes from the kiln be dangerous to be around, even outside. Would
it even make a practical raku kiln? I haven't done any raku but would
like to try it so this might be my chance... :)

Is there anything else I could use it for or would I be better off just
tossing the whole thing?

Thanks

-Kit Shannon in Alaska

wayneinkeywest on wed 12 nov 03


Mel, and other experts...could ITC be used to "coat" the inside surface of
the kiln, and shield the pots inside from lead fuming?
Wayne Seidl

> Hi. I've just gotten out of a community studio situation by building my
> own studio. I've been making pots part time for about 8 years now, but
> i'm on my own now and have a question. I recently acuired a very old,
> homemade, electric kiln. It is pretty small, maybe 14 inches wide by 24
> inches tall. I didn't really need the kiln because I just bought a
> brand new kiln but I couldn't turn down a FREE kiln. The lady I got it
> from hadn't made pots for probably 20 years or more. I bought her old
> wheel and she gave me lots of glaze materials, magazines, etc. Anyway,
> after I had most of the stuff and the kiln loaded into my truck, she
> pulls out this big bag of white lead and asks if I want it!!! Of course
> I told her no no no, but now I realize I can't really use this kiln to
> even bisque in cause it and the shelves and posts probably have lead
> contamination. I thought about giving it away, but I don't really trust
> someone else to understand it can't be used for functional work...
> But what can I do with it...
>
> I've read the archives about lead contamitation a little but I'm still
> unsure how to procede with this kiln...
>
> Can I take all the wiring out and convert it into a raku kiln? Or would
> the fumes from the kiln be dangerous to be around, even outside. Would
> it even make a practical raku kiln? I haven't done any raku but would
> like to try it so this might be my chance... :)
>
> Is there anything else I could use it for or would I be better off just
> tossing the whole thing?
>
> Thanks
>
> -Kit Shannon in Alaska

John Hesselberth on thu 13 nov 03


Hi Kit,

Here's an idea you might try. First go to a hardware store and buy one
of the kits you can use to test for lead paint. They are useful on
ceramic surfaces also. Test the kiln in its current state. If you find
lead, fire it empty with all the peeps open and the lid propped up a
bit (I assume it doesn't have a kiln vent, but if it does use that
too). Do it in a well ventilated area--preferably outside. Try to get
it up to cone 6 or 8. Do that a couple of times. Then retest and see if
the lead has been purged.

And let us know if you try it whether or not it works. This question
comes up from somebody a couple times a year.

Regards,

John
On Wednesday, November 12, 2003, at 09:05 PM, wayneinkeywest wrote:

>> she
>> pulls out this big bag of white lead and asks if I want it!!! Of
>> course
>> I told her no no no, but now I realize I can't really use this kiln to
>> even bisque in cause it and the shelves and posts probably have lead
>> contamination. I thought about giving it away, but I don't really
>> trust
>> someone else to understand it can't be used for functional work...
>> But what can I do with it...
http://www.frogpondpottery.com
http://www.masteringglazes.com

Bruce Girrell on thu 13 nov 03


> Try to get it up to cone 6 or 8. Do that a couple of times.

Get it as high as it will go. The vapor pressure of lead increases
dramatically with temperature. You would need to get to 1740 deg C to boil
the lead (760 mm vapor pressure), but at cone 10 you'd be looking at about
30 mm vapor pressure, which should do a lot of good. At cone 8 you'd have
about 20 mm, cone 6 about 15 mm, and at cone 06 about 1 mm. The longer you
can afford to keep it at the peak temperature, the better.

Bruce "just had to go and look it up" Girrell

Snail Scott on thu 13 nov 03


At 11:13 AM 11/12/03 -0900, you wrote:
>I realize I can't really use this kiln to
>even bisque in case it and the shelves and posts probably have lead
>contamination...


If it will handle high-fire, fire it as hot as
you can for quite a while; much of the lead may
burn out. And then you can test to see how much
is actually remaining in the kiln.

-Snail