Comment

Comment by Erik Evans on April 26, 2016 at 8:05pm

Thank you, gentlemen, for such useful information.

Comment by Norm Stuart on April 23, 2016 at 10:02pm

Vinegar is not a great way to flocculate glazes which include carbonates, as it foams up like you mixed vinegar with baking soda. And flocculating the glaze is what Tony is doing in the video with the vinegar.

My favorite flocculant so far is ammonium sulfate. As with vinegar both ions of this white salt-like ammonium sulfate fertilizer burn out in the kiln, leaving the glaze unchanged.  The only drawback it is converts any copper carbonate you add into dark blue copper sulfate, which is soluble. But the glaze fires the same.

Our older standby to flocculate glazes is calcium chloride, used in colder climate to sprinkle on sidewalks and melt ice.  The calcium remains behind after firing, but most glazes can tolerate some extra calcium.

I don't like epsom salts because adding magnesium increases surface tension of the glaze and sometimes changes the glaze color.

Things you can use to gel a glaze (aka flocculate it)

Comment by Mary Pendergast on April 23, 2016 at 6:29pm

I would love to learn more about when you use vinegar. Thanks for your video.

Comment by Bev Lev on March 21, 2016 at 5:52am

thanks for posting this...got to try it!

Comment by juli long on June 28, 2015 at 2:56pm

I added his other video, "help for gertsley borate suffers" My question is, are all my glazes supposed to look like his, and use one dip for perfect coverage? Maybe thats why my glazes suffer.

Comment by George Lewter on June 28, 2015 at 7:53am

This is an excellent short video from Tony Hansen on how to get a glaze to sheet a bisque piece and then stop moving to eliminate unwanted drips. Nice work, Tony.