October 26th 03, 10:00 AM
Yes you can Glaze pots at the greenware stage - they can also be glazed at
the bone dry stage.
For a glaze to work on greenware it has to accomodate the shrinkage that
occurs as the clay dries, in practice this usually means having a glaze with
ball clay in it (30% is a rough guide). The glaze then has to be
re-formulated that is other ingredients adjusted so that the fired glaze has
the same proportion of the various oxides (not such a daunting task witha
glaze calculation program).
You may find recipes for suitable glazes, probably referred to as "slip
If you then want to fire the pots in one go (once firing) the firing cycle
has to be adjusted so that it starts like a biscuit firing has about an hour
soak at 900 deg Celsius, and then continues like a glaze firing.
To glaze at the bone dry stage you may get away with using a glaze
formulated for biscuit if it has some clay in it or add about 5% bentonite
to a biscuit glaze (don't just add to the liquid glaze -either mix into dry
igredients or if you have to add to an already mixed glaze mix with a small
amount of the glaz and then sieve it into the glaze mix).
Dennis Parks wrote a book - can't remeber the exact title but something like
"Oil firing and Raw glazing"
Also Andrew Holden "The self reliant potter" published around 1980 has a
section on raw glazing
Iv' just rembered tha Fran Tristram has a book about Once firing publishe by
Have your eyes started to glaze yet??
It isn't really as daunting as it sounds just have a go!
"NoSpam" > wrote in message
> Why can't one put glaze on Greenware? I don't understand...
> I think the glaze would just soke into the greenware and leave the color
> The glaze is just a glass sealer. What would happend if one glazed
> Does the greenware shrink in the kiln? Can someone explain?