Saturday, October 12, 2013

Last Outdoor Glazing

Finishing up the last glazing today for a ^6 reduction soda. This will probably be the last firing for which I can glaze outside, which is a bummer: glazing is such a messy business, and my studio inside is pretty small. In the winter I have to do a minor re-arrange every time it's time to glaze. It's a bit chilly out there today, but I don't mind: I've got my hot flashes to keep me warm.

This firing will include 8 test glazes and two flashing slip variations; basically to bring a flashing slip from^10 to ^6 you can usually just add 5-8% Neph Sy to the existing recipe. Write that down! That's my pearl of wisdom for today. That, and, if you are in a hurry, a kind of boilerplate approach to dropping a glaze from ^10 to ^6 is to replace to feldspar 1-for-1 with Neph Sy, and add about 10% gerstley borate. This isn't always the best way to preserve the color or the hand of the glaze but it will get you in the neighborhood. (Always keeping in mind the proportions flux of alumina and silica, which is what I have Glazemaster to help me out with. Yes, it's working again!) Alternatively, you can add 10-15% Ferro Frit 3134, which is now my favorite frit, as it is well-balanced enough itself not to require a lot of adjustment when used in this way.

Among others, I am trying again with the Amber Celadon. Here's the recipe I am testing at ^6:

Amber Celadon test

Alberta Slip          32.2
Wollastonite         12.7
Kaolin                     7.2
Gerstley Borate      9.0
Whiting                   6.8
Silica                    12.7
Neph Sy               19.5

Yellow Ochre         7.6
Bentonite               2.0

1 comment:

Unknown said...

Brilliant, these are exactly the nuggets of information I'd hoped to get from following experienced potters on blogger. Thank you so much for sharing your wisdom - keep sharing thanks :-)