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PeterH

Member Since 28 Apr 2013
Offline Last Active Today, 04:18 AM
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Posts I've Made

In Topic: Accidentally Left My Plugs Out... My Reds Look Fabulous

19 June 2015 - 08:52 PM

I'm willing to believe in almost anything influencing a copper-red glaze. However I see that Cyote Really Red

is based on a Cadmium inclusion stain.

http://www.sheffield...NT-p/cg071p.htm

 

... which AFAIK are supposed to be pretty insensitive to firing conditions.

 

Maybe Denice's prof had it right, and the glaze surrounding the stain is brighter?


In Topic: Firing Supports For Glazed Work

13 June 2015 - 04:42 PM

A couple of possible relevant quotes on hight-bisque low-glost:

 

from: http://lindaarbuckle...sque-firing.pdf

Although industrial china is often bisqued high (so it can be
supported while being fired to the clay body’s maturity) then
glazed lower (using binders and gums in the glaze to help it
adhere to a body that is no longer porous), studio potters
usually bisque lower so that the work remains absorbent and
easily glazed.

 

from: https://books.google...w-glaze&f=false

... under Firing Cycle for Slip-Cast Objects

 

And a rather ambiguous quote on the process used by Boehm.

from: http://library.uthsc...09/boehm-birds/

Fine Porcelain Creation

The name “porcelain” was given to translucent vitrified stoneware in China by the explorer Marco Polo in the 13th century. He thought that it resembled a certain seashell named genus porcellana because of its high gloss and translucency. Porcelain is made up of a high temperature (2400° F) fusion of fine white clay and feldspar. To make a sculpture like the Boehm birds, the figure is first modeled in clay or wax. A mold is made from the figure (or many molds in the case of complex figures) and a cast is made by pouring the fine porcelain mixture into it. After the lining of this mold has hardened, the liquid center is poured out, and the mold is removed. At this time if the model was made in sections, the sections are assembled, and fine details are added by hand. The figure is placed in a kiln for twelve to 24 hours, then cooled for three days. At this time it is in its “bisque” state, and may be colored and then glazed, if desired.

 

I think that this is saying that a high bique was used (vitrifying the body), and a later

glost stage was optional. Obviously there would be the usually difficulties in applying

underglazes and/or glazes to a vitrous body.

... opinions to the contrary welcomed.

 

Regards, Peter


In Topic: How Does This Potter Produce This Effect?

10 June 2015 - 04:00 AM

Two images of feathering (not the same pot or worker):

 

https://jblanchardpo...eatherplate.jpg

 

http://www.ceramicar...K-W 4 small.jpg

 

Combing is similar, except you use a (comb like) tool with multiple points.


In Topic: Thinning Slip Water Or Deflocculant?

09 June 2015 - 04:32 AM

This video may be of interest, especially from 3:50


In Topic: Wollastonite Chunks In Glaze - Fix?

29 May 2015 - 03:37 PM

I thought of a mortar and pestal, but I don't see that as a long term fix.  I like this glaze and plan to mix it in larger batches which I will be using a great deal of.

 

 

... I suspect rayaldridge is right, and the quantity involved is/should-not-be significant. However if

you are going to make this glaze repeatedly, and you are certain that it's the wollastonite staying

in the sieve, why not just add a little more to allow for loss-on-sieving?