Mixing Glaze And Underglaze

[ClayPigeon]

Hi all, I'm be where so I hope this hasn't been posted before. I did a check and couldn't find anything so maybe the answer is obvious?

 

Anyway, can I mix a glaze and an underglaze together to use on green ware for sgraffito? Im trying to make a pale pink and could only find a white glaze and a pink underglaze.

 

Thank you!!

[perkolator]

yes you can.  just more difficult to replicate since they're both in liquid form (with unknown water content) vs being able to weigh dry materials for batch consistency.

[ClayPigeon]

Thank you Perkolator! I'm very new to pottery so please bear with me as I ask these probably very obvious questions. What do you mean by replicate? My concern is that if I use a regular white glaze on earthenware to carve a design, it will not come out looking how it should (white) and if I mix it with the pink underglaze, will it come out pink, or some other weird colour? I was under the impression you could only use glaze on bisque ware, but underglaze could goon bisque ware or green ware.

[oldlady]

i think that the reason it might work is that you are using the underglaze for its color content only.  at least that is what your original question seemed to ask.  now i am not so sure. "replicate" means to make that same color again but it does not seem that you care about that aspect of the problem.

 

it does appear that you could benefit from some basic knowledge.  there are lots of books that explain the process of taking a piece of clay from mud to finished product.  once you know a little more, your questions will be easier to answer.

[Chris Campbell]

The problem you are going to have is trying to get a successful sgraffito result with glaze.

Glazes move and will tend to fill in your lines.

Under glazes stay where you put them which is why they do well ... Slips also stay put so ...

if your clay is white you could make a slip, add the pink underglaze for color and do the carving.

[alabama]

Hey,

Sooo, why wouldn't you want to make sgrafitto the regular way with redware cone 06 clay coated with white slip then

carved on, bisqued, then glazed in 06 or 04 clear?  If you're trying to replicate 18th century earthenware sgrafitto, that is

the best known way to do it.  Make sure the clear glaze isn't too thick or it might cloud up defeating your carved

design's purpose.  Trying to use a white glaze and underglazes is making this project difficult if not improbable.

You can also use a white clay body and a dark slip for colonial sgrafitto pottery.

 

Hope this helps.

Alabama

[neilestrick]

There's a chance the glaze and underglaze won't play nice together and will bubble up or pinhole or whatever. There's also a chance that it won't like going onto greenware and will do something bad there,too. If it does melt/fuse/behave fine, you're most likely going to end up with a surface that's glassier than an underglaze, but more matte than the glaze, and it most likely will be too glassy for it to take glaze if you bisque fire it onto the pot. So if you're planning to put a clear glaze over it you'll have problems. A better solution is to get a white underglaze to dilute it with, or just apply it thin so it's not as intense, or as Chris suggested, use it to color a slip.

[Benzine]

Neil, that's what I was thinking as well.  In my experience, underglaze doesn't turn out well, when placed on glaze.

 

I wasn't sure if the original poster was asking about mixing underglaze and glaze, in terms of just layering them, or actually mixing them while liquid.

[ClayPigeon]

Thank you for all of your input and suggestions. Much appreciated.