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Marcia Selsor

Member Since 16 May 2010
Offline Last Active Yesterday, 08:48 PM
*****

Posts I've Made

In Topic: Can I Tumblestack Underglaze Greenware For The Bisque Fire?

28 August 2015 - 08:04 PM

should be fine. 

marcia


In Topic: Proper Reduction Firing Schedule

27 August 2015 - 03:45 PM

I fired ^6 reduction for 20 years when I was teaching after doing ^9-10 for 12 years prior to that. . I did a body reduction for both

firings from about 09-04.  If you are going for copper reds you should take it up in a reduced /neutral atmosphere. 

I reduced towards the ends of the glaze firings around 8-10 or 5-6 depending on which I was firing.

 

Marcia


In Topic: Silicon Carbide

27 August 2015 - 01:07 PM

here is an article from Ceramics Art Daily (upper left header)

http://ceramicartsda...8-04-oxidation/


In Topic: Over Fired

26 August 2015 - 10:25 AM

I hope you post the results. It is good to know what happens when that happens.

Marcia


In Topic: Lichen Glaze "peels" Off When Applied

24 August 2015 - 06:49 AM

SAS, 

The first link is to Robin Hopper's article on Ceramic Arts Daily (see upper left hand header to access the CAD

 

 

 

http://ceramicartsda...ramic-surfaces/

 

Next is Alisa Clausen's post from Clayart regarding mark Bell's Lichen which is in Lana Wilson's book. Alisa is the only one who mentions application requirements. Possibly there are dome more directions in Lana Wilson's book.

 

Lichen Glazes are fun to use but tricky.You could google "applying lichen glazes for more information.

Marcia

 

Alisa Clausen on mon 21 feb 05

Glaze test for Mark Bell's Lichen Glaze, cone 6 ox. 
Glaze tested on white midrange stoneware fired in electric oxidation to = 
1240c. (2264f) 

Source: 
Credited to: Mark Bell 

Firing ramp: 
100c p/h to 600c (212f - 1112f) 
150c p/h to 1140c (302f - 2084f)=20 
80c p/h to 1240c (176f - 2264f) 
10 min. soak 
cool down max. to 1100c (2012f) 
Hold 1 hour 
Shut off kiln 

Recipe: 
30 Soda Spar 
31 Magnesium Carb. 
6 Frit 25 
8 Talc 
6 Zinc Oxide 
10 Kaolin 

Note: All raw materials are measured up or down to the nearest half = 
decimal. =20 
Colorants or additives to a 100 gram test batch are measured in percent = 
to the 100 gram test batch. 

Results: 
The application of this glaze is crucial. It must be applied thickly = 
enough that it dries with slight cracks over the dried surface. 

This recipe is very similar to Brian Kemp's recipe, with the addition of = 
Zinc Oxide.=20 
The glaze forms small, close, irregularly shaped curdles. They are have = 
a more mat surface than the Kemp recipe. The addition=20 
of Zinc also makes the overall glaze slightly drier and the edges of the = 
curdles are slightly lifted. The overall feel is craggy and rough. 
It resembles lichen moss and although the edges are lifted, they are = 
fused. 

With 3% added Rutile 
Same as above, but slightly larger lichen forms, color is also the same. 

Over Commercial Black cone 04 glaze 
the curdles smoothed out, are in general larger and glossier. The Black = 
glaze pools in between the curdles. 

Regards from Alisa in Denmark