Ann Brink on sat 5 jun 04
Hi Martin, I understand completely why you want to mix your own glazes for
lo-fire--my temperament doesn't fit the brush, brush, brush routine either.
I've mostly used one base glaze for years- found the recipe in an OLD
ceramics magazine article by Glen Lukens, a southern CA pottery pioneer. I
hope you can get gerstley borate, because it is: (^06)- 650 gr. feldspar,
400 gr.
Gerstley Borate. Add oxides for colors. For yellow I add Mason stain
Marigold. You will want to do some tests with adding an opacifier too.
When I first started using this glaze I was a fairly new potter and measured
by volume, in other words, 6and a half Cups Feldspar, 4 Cups G. Borate.
Didn't know any better. However, in this case, it worked, so I haven't
changed. Feldspar is a little heavier than GB, and I fire to ^04 usually,
so it seemed to work out.
And yes, it is constantly used for food. I tell people to start with a cold
oven, to avoid thermal shock. I go easy on the copper- it doesn't take much
to make a nice green/turquoise. Another thing I do is make rim feet and
glaze the bottoms. Or you can use stilts. I'd just rather make rim feet
than fool around with stilts. If you are in a climate like Louisiana where
everything molds, earthenware can give you trouble. Try to fire it as hot
as it can stand. Oh, for the exterior I do use a commercial clear and
brush one light coat on, after thinning the glaze with water. I didn't like
the high gloss on terra cotta- just want to flux & darken the surface.
Hope this helps- ask if you need more details.
Ann Brink in Lompoc Calif.
(just finished admiring the 3 oval trays I made yesterday. I used rollers
for texture, and threw the feet. Good thing I have all these nice wooden
trays from garage sales, to slump slabs in.)
Martin Rice in Costa Rica wrote: > Dear Ann:
> Here's the thing. The only clay available here is low fire, terra cotta
> colored earthenware. There are two sources, one a ^04 and one a ^05. This
is
> what I've been using. The only glazes I've found are some Duncan things
> which I don't particularly like. I'd like to mix my own, and I like the
idea
> of clear glaze as you use and just a very few colors. One of the problems
> I've had is finding recipes for low-fire glazes. Also, if they require
> frits, they're impossible to get here.
>
>.
| |
|
