Michael McDowell on sat 3 jul 04
In the past, I have taken note of the principles of commercial ware
dryers as they have been discussed on this list. But I had been
using a clay body that didn't seem to require that I take any such
steps. Lately I have switched to a clay body that is much closer to
porcelain or B-mix, and I've been having real troubles with cracks
appearing around handle attachments and such. I've been dealing with
it with mixed success by just slowing down the drying process,
loosely covering the pieces with plastic sheeting. But some cracking
around handles was still going on, and I was not happy with the
extra time it was taking to get things ready for bisque. So, I
decided to try and make some kind of drying cabinet.
I have an old bakers cart that I had covered the sides of with
plastic sheeting to make a damp box. It has 2' wide angle iron slots
every four inches up the sides, 3' deep and about 5' high. I also
had a food dehydrator that works on natural draft, with a heating
element in the open bottom and a cutting board top that is partly
slid off the top to adjust the amount of draft. I took the heating
element out of the food dehydrator and placed it in the open bottom
shelf of my damp box. On the next shelf I spanned with some 1"x3"
boards to support two cookie sheets which I filled with water. I
broke up a big plaster bat and laid the pieces partly into the water
and over the sides of the sheets. The plaster wicks up the water and
transmits it to the heated air rising past the heating element. The
top of my baker's cart/damp box had been closed off with three 1' x
2' plywood boards. The two boards on either end are attached to
plastic sheets that cover the ends of the cart, but the center one
is free to move. So I just popped it up and laid it over it's
neighbor enough to open about a 1/4" to 1/2" slot across the top.
I've never actually seen a commercial dryer, but this seemed to
create the conditions of elevated temperature and humidity, with a
certain amount of air exchange.
Well, I'm happy to report that this has been an unqualified success!
I've run two batches of "batter bowls" through it now. They are sort
of shaped like giant teacups with pour spouts. These handles had
been doing quite a bit of cracking before. I just put them in this
dryer as soon as all the attachments are done, plug in the heating
element and let it go. I've been finishing up around midnight these
last two nights. By late afternoon the next day the pieces are dry
enough that they are past all likelihood of further cracking. There
was a very little cracking on the first batch, but then I closed
down the crack on the top to reduce the air flow and allow for
higher temperature to develop. This second batch showed no trace of
cracking. I'm sold.
Now I'm hoping someone on the list could share with me where I would
go to get the parts I'd need to build a couple more of these heating
elements. If somebody reading this has that kind of knowledge,
contact me directly and I'll send pics.
Michael McDowell
Whatcom County, WA
Michael@McDowellPottery.com
http://www.McDowellPottery.com
wayneinkeywest on sun 4 jul 04
Michael:
Your server is rejecting my address for some reason.
Send the pix to wayneinkeywest AT bellsouth.net. I'll see what I
can dig up.
Wayne Seidl
Key West, Florida, USA
North America, Terra
Latitude 81.45W, Longitude 24.33N
Elevation 3.1 feet (1m)
----- Original Message -----
From: "Michael McDowell"
To:
Sent: Sunday, July 04, 2004 1:21 AM
Subject: A home made drying cabinet
> In the past, I have taken note of the principles of commercial
ware
> dryers as they have been discussed on this list. But I had been
> using a clay body that didn't seem to require that I take any such
> steps. Lately I have switched to a clay body that is much closer
to
> porcelain or B-mix, and I've been having real troubles with cracks
> appearing around handle attachments and such. I've been dealing
with
> it with mixed success by just slowing down the drying process,
> loosely covering the pieces with plastic sheeting. But some
cracking
> around handles was still going on, and I was not happy with the
> extra time it was taking to get things ready for bisque. So, I
> decided to try and make some kind of drying cabinet.
>
> I have an old bakers cart that I had covered the sides of with
> plastic sheeting to make a damp box. It has 2' wide angle iron
slots
> every four inches up the sides, 3' deep and about 5' high. I also
> had a food dehydrator that works on natural draft, with a heating
> element in the open bottom and a cutting board top that is partly
> slid off the top to adjust the amount of draft. I took the heating
> element out of the food dehydrator and placed it in the open
bottom
> shelf of my damp box. On the next shelf I spanned with some 1"x3"
> boards to support two cookie sheets which I filled with water. I
> broke up a big plaster bat and laid the pieces partly into the
water
> and over the sides of the sheets. The plaster wicks up the water
and
> transmits it to the heated air rising past the heating element.
The
> top of my baker's cart/damp box had been closed off with three 1'
x
> 2' plywood boards. The two boards on either end are attached to
> plastic sheets that cover the ends of the cart, but the center one
> is free to move. So I just popped it up and laid it over it's
> neighbor enough to open about a 1/4" to 1/2" slot across the top.
> I've never actually seen a commercial dryer, but this seemed to
> create the conditions of elevated temperature and humidity, with a
> certain amount of air exchange.
>
> Well, I'm happy to report that this has been an unqualified
success!
> I've run two batches of "batter bowls" through it now. They are
sort
> of shaped like giant teacups with pour spouts. These handles had
> been doing quite a bit of cracking before. I just put them in this
> dryer as soon as all the attachments are done, plug in the heating
> element and let it go. I've been finishing up around midnight
these
> last two nights. By late afternoon the next day the pieces are dry
> enough that they are past all likelihood of further cracking.
There
> was a very little cracking on the first batch, but then I closed
> down the crack on the top to reduce the air flow and allow for
> higher temperature to develop. This second batch showed no trace
of
> cracking. I'm sold.
>
> Now I'm hoping someone on the list could share with me where I
would
> go to get the parts I'd need to build a couple more of these
heating
> elements. If somebody reading this has that kind of knowledge,
> contact me directly and I'll send pics.
>
> Michael McDowell
> Whatcom County, WA
> Michael@McDowellPottery.com
> http://www.McDowellPottery.com
>
>
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