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duncan's cover coat

updated thu 11 apr 02

 

Karen Shapiro on tue 9 apr 02


Hi all,

Just wondering if anyone has had experience with the Cover Coat greenware underglazes made by Duncan. I've heard they can be "tricky", but don't know how that was meant. What's your take on it?

thanks,

Karen in Gualala



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Valice Raffi on wed 10 apr 02


Karen,

I've used Cover Coat underglazes for years. Most of the time, I've thinned
them with water and used in a "watercolorish" way. When I do that, I can
get a few (maybe up to 5?) thin layers on, then I have to fire to "set" the
color before adding more. Although Duncan says they are for greenware,
I've been using this method on bisque for about a decade with no problems.
My method doesn't work on greenware, the piece would fall apart!

Most of the times that I've tried using them for opaque coverage (their
intended use), I've been disappointed with the results. Because of the
amount of clay in the recipe (I've heard that its 50%), there are usually
thick brush marks, which I don't care for in my work. I have had students
apply it too thickly and it peeled back under the clear coat which was
horribly ugly. Maybe that's what's meant by "tricky".

Valice
in Sacramento - always amazed by the number of students who think that 3
coats of glaze is just a starting point!

>Just wondering if anyone has had experience with the Cover Coat greenware
>underglazes made by Duncan. I've heard they can be "tricky", but don't
>know how that was meant. What's your take on it?
>
>thanks,
>
>Karen in Gualala