What kind of medium do you use to paint with enamels?

by Lance McQuinn
(Novato, Calif.)

We're making a stained glass window of the world and need to paint the land onto the water with enamel. I have some powdered enamel, but I don't know what kind of medium to use. Also, what temperature do I fire it to?

Milly's reply:
Wow, sounds like a really ambitious project! You can use lots of different mediums. Water is the easiest and gives the liveliest line, but it dries quickly so doesn't give you much time. Use it with a tiny bit of gum arabic - this will help with the flow and adhesion.
Alternatively you can use Damar varnish-used by oil painters-with distilled turpentine as the thinner. This gives more time, and is easier to paint lines with. Crucially, it allows you to overpaint with a water-based mix once it has dried, which means that you can fire two layers of glass paint at the same time, saving power.
Glass paints and enamels fire at between 550-650 centigrade.
I'd love to see your stained glass world once it's finished.