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Hi! Can anyone suggest what to do if I fired my items at cone 5, after glazing them with Amaco Seaweed PC-42, and I got a bunch of pinholes, and even one sharp bubble on the top rim of a cup?
I'm using a medium-sized Cress electric kiln (all digital, so no cone sitter). I set it at cone 5, medium speed, and no hold.
Help and suggestions greatly appreciated!
What claybody are you using? Did you apply any underglaze, oxide, or wash?
I've had pinholes in other glazes and have heard of several explanations. There may be organic matter in your claybody or an underglaze - as it heats up it pops thru the glaze. Or, some glazes just do this. Solution is to insure a longer cooling period so that the glaze has a chance to reform.
There may be other explanations but generally the solution is the same. Slow cooling.
I'm still doing experiments on my pinhole issue but a slight hold might work too - but be cautious of too long of a hold at high temp since other glazes may run.