Copper Carbonate + Underglazes In Same Firing

[Isculpt]

I usually apply a copper carbonate wash to my sculptures after bisque firing to 06. Then I fire them with the copper carbonate wash again at 06, and then I underglaze and re-fire at cone 2 or whatever is required. My firing schedule just got shortened by a few days, and I'm wondering if I can apply the copper carbonate wash (which is rubbed off and left in crevices) and then apply the underglaze on top of that without the usual in-between firing, proceeding instead to the cone 2 firing. As usual, I'm breathlessly awaiting a reply!

[Denice]

I usually apply a copper carbonate wash to my sculptures after bisque firing to 06. Then I fire them with the copper carbonate wash again at 06, and then I underglaze and re-fire at cone 2 or whatever is required. My firing schedule just got shortened by a few days, and I'm wondering if I can apply the copper carbonate wash (which is rubbed off and left in crevices) and then apply the underglaze on top of that without the usual in-between firing, proceeding instead to the cone 2 firing. As usual, I'm breathlessly awaiting a reply!

 

 

I have never prefired a oxide wash before putting a glaze over it, depending on the glaze their can be some fluxing between the two and cause some bubbling, I don't know if prefiring would prevent this. You should probably throw a test pot in your next firing to see how it works with the underglaze your currently using. Denice

[Marcia Selsor]

I don't see why not. I wonder what the purpose was in firing three times. The underglaze and copper wash should work together unless there is much volitzation burning off from the copper. But you are firing hotter for the underglaze so you could anticipate more burnoff. If that isn't happening, then no problem. Test first as always in ceramics.

Marcia