Gayle Bair on thu 14 jun 01
I hope all the responses are posted to the list as I am interested in this
subject.
Gayle Bair- Bainbridge Island WA
Nikki Wrote>>
I moving to single fire and at the same time I am also RElearning glaze
making using Insight AND I am now obsessed (darn you, I mean, thank you Ron,
John, Will) with durable/food safe/etc glazes. I make functional kitchen
ware.
I have decided to start approaching single fire with Tony's 3 Cone 6 glazes:
clear, matte, and glossy. I would like to hear if anyone else is single
firing with the glazes. Please share your thoughts and experiences.
What kinds of adjustments have you made to the recipes?
Do you glaze wet, leather hard, bone dry?
Do you spray, dip, paint?
Do you do any decorative work under or over the glaze?
If the glaze cracks as it dries, do you fire it anyway? How does it turn
out?
Nikki Simmons on thu 14 jun 01
Let me start by saying, I have been living in the archives for the past few
months. Now I want to talk to some real live people...
I moving to single fire and at the same time I am also RElearning glaze
making using Insight AND I am now obsessed (darn you, I mean, thank you Ron,
John, Will) with durable/food safe/etc glazes. I make functional kitchen
ware.
I have decided to start approaching single fire with Tony's 3 Cone 6 glazes:
clear, matte, and glossy. I would like to hear if anyone else is single
firing with the glazes. Please share your thoughts and experiences.
What kinds of adjustments have you made to the recipes?
Do you glaze wet, leather hard, bone dry?
Do you spray, dip, paint?
Do you do any decorative work under or over the glaze?
If the glaze cracks as it dries, do you fire it anyway? How does it turn
out?
Sincerely,
Nikki Simmons
nsimmons@mid-mo.net
Dave Finkelnburg on fri 15 jun 01
Nikki,
In general, my experience has been almost any glaze will adhere to bone
dry greenware. However, the thinner the work the more it has to be glazed
carefully to single-fire. Very thin, bone dry greenware has a bad habit of
cracking when green glazed. Such ware is better glazed at leather hard, but
that takes a glaze with enough clay in it to shrink during the drying
process. Otherwise you get glaze flaking off.
I have found that patient, slow glazing with a spray gun or a brush,
sometimes over two days, with drying periods in between, is one way to glaze
bone dry greenware without a high failure rate. Keep in mind I am in an
extremely dry climate (typical summer daytime relative humidity is less than
15%) so bone dry for me is really, really dry. Things like handles fail the
most readily. They seem to soak up glaze too fast and crack in the middle.
I see differences between the same glaze fired on greenware and fired on
bisque. I put the difference to more outgassing of the clay body through
the glaze. The difference is most apparent on glazes with a lot of boron,
which makes sense, since it melts at a low temperature and would then tend
to be disturbed (literally stirred) by the outgassing.
In my limited experience, if the glaze cracks as it dries it's probably
going to crawl, whether fired on greenware or on bisque. You need to
correct that problem, regardless of whether you fire once or twice.
Good glazing!
Dave Finkelnburg, enjoying an Idaho summer. Yesterday it snowed.
Last night the tender grape leaves froze, even under the blankets. It's
supposed to be 80-degrees F on Saturday.
Martin Howard on fri 15 jun 01
fast and crack in the middle.>
I have had that problem with slip and glaze at leather and bone dry. So, for
those things with handles I have reverted to bisque firing.
Slipping thin ware with delicate handles tends to not just cause the pot to
crack, but the weight of the handle pulls the side out off the pot. So, the
decoration tends to become based on glaze, rather than slip, as far as I am
concerned at present.
Looking forward to a new spray booth.
Martin Howard
Webb's Cottage Pottery
Woolpits Road, Great Saling
BRAINTREE, Essex CM7 5DZ
England
martin@webbscottage.co.uk
http://www.webbscottage.co.uk
John Forstall on fri 15 jun 01
Nikki,
Been single firing for 15 years. Been studying DigitalFire for 15 days.
The former is easy, the later difficult. I'll try to answer your questions
from my experience. First the 5 x 20 glossy single fired on Standard
Ceramics #130 porcelain and my chemicals was opaque with tiny trapped
bubbles and not attractive over my slips. The mat was more glossy than the
glossy.
>What kinds of adjustments have you made to the recipes?
None, but have used the software to make successful adjustments to my clear
glaze that was crazing.
>Do you glaze wet, leather hard, bone dry?
Interiors are poured leather-hard. Exteriors are sprayed bone-dry.
>Do you do any decorative work under or over the glaze?
I rely on the glaze to do most of the decoration. In oxidation that means
layering, trailing, splattering, etc.
>If the glaze cracks as it dries, do you fire it anyway?
A network of tiny cracks can usually be smoothed by finger rubs and fire OK,
but this is troublesome and usually indicates too much kaolin in the glaze.
Part, or all EPK can be changed to ball clay to reduce shrinkage and stop
the drying cracks.
Single firing has most of it's problems associated with glaze application.
If the ware is dry and fired slow there is little difference between firing
greenware with glaze applied, and firing greenware with slips applied to a
bisque temperature. However, it is not a trouble free short cut, and seems
most important to fit the needs, ware, and personality of the potter. One,
or two more lifetimes would come in handy.
John
(John Forstall, Pensacola, FL.)
From: Nikki Simmons
Subject: Single Firing/DigitalFire/RR JH WE
Comments: To: thansen@digitalfire.com
MIME-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Let me start by saying, I have been living in the archives for the past few
months. Now I want to talk to some real live people...
I moving to single fire and at the same time I am also RElearning glaze
making using Insight AND I am now obsessed (darn you, I mean, thank you Ron,
John, Will) with durable/food safe/etc glazes. I make functional kitchen
ware.
I have decided to start approaching single fire with Tony's 3 Cone 6 glazes:
clear, matte, and glossy. I would like to hear if anyone else is single
firing with the glazes. Please share your thoughts and experiences.
What kinds of adjustments have you made to the recipes?
Do you glaze wet, leather hard, bone dry?
Do you spray, dip, paint?
Do you do any decorative work under or over the glaze?
If the glaze cracks as it dries, do you fire it anyway? How does it turn
out?
Sincerely,
Nikki Simmons
nsimmons@mid-mo.net
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