Enhancing commercially made cups

[HomemadeSunshine]

I've been doing some tests on commercially made ceramic mugs, to see how I can improve them. I have had the most luck with decals, which I fire to ^06. The only thing is that I have had some go metallic or get really small bubbles on the glaze. I'm not sure why this is.

 

Has anyone else done this? Or could tell me about the commercial ceramics process (especially kiln temperature)? Other input?

[bciskepottery]

Cone 06 seems a bit high for decals; when I did some decals on tiles I think I only fired to cone 016. Check the decal manufacturer's info.

[neilestrick]

The original glaze on that mug may have been fired to cone 06. So if you're firing the decal at that temp, you're re-melting the glaze. Typically decals are fired much lower, like cone 017, so the glaze doesn't melt.

[HomemadeSunshine]

I'm not sure that's it, because they didn't really melt, just changed a bit and when ever I do decals on ^10 pieces, I refire to ^06 fine. Is there any way for me to figure out what temp the cups were originally fired to aside from testing until it melts?

[bciskepottery]

Most/majority of mass produced commercial ware is bisque fired to vitrification, then glazed fired at low temperatures. You could try contacting the manufacturer and hope they tell you the glaze temperature. If they do not wish to part with their proprietary knowledge. testing is your only option. Or, fire a couple pieces at lower tempertures and see if that makes a difference.