Gold Luster firing questions and schedule, help!

[boardbutproductive]

Hi all!  I am hoping to do my first luster firing this week, using Duncan Bright Gold.  I have 8 pieces ready to use, all fired to cone 5 with glossy glazes.  I have a good idea of how the process works, and am prepared with the supplies and a well-ventilated workspace.  I have a few outstanding questions though... can anyone help with these?

1) How many coats of the luster do you apply?  I've watched videos where people recommend both 1 and 2 coats.  

2) When you fire the pieces, do you run the kiln on low and medium for a certain amount of time before switching to high?  I have a very small manual electric kiln with a kiln sitter, one switch, one peephole and no pyrometer.  So it is just low, medium, high.  For glaze firings, I usually do 2 hrs low, 2 hrs medium and then high for as long as it takes to drop the sitter.  Do I still follow this 4-hr preheat schedule for luster?  Or do I just crank it up to high at the get-go?

3) Should the kiln be vented/peephole open?  Or should the whole thing be sealed up?

4) I've read that you shouldn't "overload" the kiln for luster firings.  How much space should be between pieces to prevent that?  And can you stack a second shelf of items, or would that restrict airflow too much?

[Bill Kielb]

I would suggest reading the article in the link below  start to finish, it addresses most of your questions. If after reading, you may have some new questions to post. Lusters need ventilation in application and during firing. Lusters fire around cone 018 so not very hot compared to your normal glaze firing. Lusters generally can be fired very quickly. The fired luster is influenced by the glaze it is fired on. Too thin an application will not end up shiny and gold. Too thick can drip. Much of this knowledge is obtained by experience so in the beginning maybe some test pieces before applying it to your best work.

Here is a good article that is a nice overview IMO. https://ceramicartsnetwork.org/daily/pottery-making-techniques/ceramic-glazing-techniques/use-ceramic-luster-glaze/

[douglas]

Remember that some of companies telling you the fumes are safe are the same companies that used encapsulated lead in frits into the 80s and 90s insisting that was food safe.  That doesn't prove they are doing the same thing with luster glazes, but I'd recommend erring on the side of safety and not being around the kiln when firing.

Supposedly it is best to apply the luster as soon before firing as possible.  At least according to the potters I know who use luster.  I'd fire one piece, not all 8, so you can learn from the right amount of luster to apply. I've over and under done it, and the results are pretty ugly when not done right.