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ramp firing schedule

updated mon 14 may 01

 

Jim and Marge Wade on fri 11 may 01


Can anyone help me with a ramp schedule for a once fire ^05? I've misplaced
the one I got from a local clay art center. I've looked in the archives but
can't find one that I feel is slow enough. I did a workshop at a local
elementary school a week ago where the kids made masks with a low fire clay.
They applied underglazes to them and I will brush on a clear glaze before
they're fired. A few have some cracks as not everyone rolled their slab
thin enough (my daughter's included...don't they listen?). It was suggested
to me to mix a little toilet paper with hot water into a pulp and add it
50/50 to some slip, working it down into the cracks. Do you think that will
work or does anyone have a better idea? Most of the pieces should be pretty
dry by now, but I was still planning on holding at 180 for 10 - 12 hours
(too long?). I also want to hold for an hour at the end. My original
schedule also had a hold around 600 degrees to be sure any chemical water
was burned out. Is this necessary?

I didn't realize that I had lost the schedule until I was on my way to the
school today to glaze/fire. Maybe I'm being overly conservative, but I'd
rather be over cautious and fire slowly. The masks turned out great. Some
are complete with feathers and nose rings! The suggestion came from Clayart,
so thanks!

Marge

Rod, Marian, and Holly Morris on sat 12 may 01


I've fired a LOT of kids work in my day. If the work is BONE dry, I just
follow a simple ramp schedule, as suggested in both the Evenheat manual at
school , and my Skutt at home (both are relatively small kilns).
Candle on low/low (2/2 on the Skutt) for 2-3 hours, then Med/Med (4.5/4.5 on
the Skutt) for 2-3 hours, then MedHi/MedHi, (or 6/6 on my Skutt) till the
cone goes down- usually less than 2 hours). If the work is dry leather
candle with lots of air (lid open 2-3" and all holes open, with only the
bottom switch to lo). When the work is not bone dry is when it pays to
candle for longer- up to twelve hours, or overnight. Longer at Med (600-800)
will not hurt a thing, except use up electricity, but I personally have not
seen it to help much, either.

I am able to be pretty cavallier about the firing schedule because I have
learned that it is really the selection of clay that makes the big
difference with kids work, mainly because they don't/can't produce even
thickness, as you have noticed.

I find terra cotta with a nice amount of grog, or lo-fire sculpture clay to
be VERY forgiving with kids work. If you are not using an open clay with
lots of grog, no amount of fiddling with the kiln will overcome the stresses
caused by uneven walls.

I've never used paper clay for repairs, but I sure do hear a lot of good
stories about it. Hope it works for you.

Marian in Michigan


----- Original Message -----
From: "Jim and Marge Wade"
To:
Sent: Friday, May 11, 2001 8:43 PM
Subject: Ramp firing schedule


> Can anyone help me with a ramp schedule for a once fire ^05? I've
misplaced
> the one I got from a local clay art center. I've looked in the archives
but
> can't find one that I feel is slow enough. I did a workshop at a local
> elementary school a week ago where the kids made masks with a low fire
clay.
> They applied underglazes to them and I will brush on a clear glaze before
> they're fired. A few have some cracks as not everyone rolled their slab
> thin enough (my daughter's included...don't they listen?). It was
suggested
> to me to mix a little toilet paper with hot water into a pulp and add it
> 50/50 to some slip, working it down into the cracks. Do you think that
will
> work or does anyone have a better idea? Most of the pieces should be
pretty
> dry by now, but I was still planning on holding at 180 for 10 - 12 hours
> (too long?). I also want to hold for an hour at the end. My original
> schedule also had a hold around 600 degrees to be sure any chemical water
> was burned out. Is this necessary?
>
> I didn't realize that I had lost the schedule until I was on my way to the
> school today to glaze/fire. Maybe I'm being overly conservative, but I'd
> rather be over cautious and fire slowly. The masks turned out great. Some
> are complete with feathers and nose rings! The suggestion came from
Clayart,
> so thanks!
>
> Marge
>
>
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