Some interesting ideas from Amir, who has done some work with Kremer mediums to make his own version of water soluble encaustics:
One is called “Translucent Wax Wall Paint Medium” (Kremer item #79228) which need to be diluted with distilled water if one intends to use it as a medium. I simply mix quality gouache paint with it and voila, water-soluble wax paint! In addition to beeswax, this emulsion contains linseed oil and casein as binders. After a painting session, I leave it overnight to fully dry then I set the paint with a heat gun the next morning. To use it as a binder to make my own paints, I mix it full strength (undiluted) with dry pigment to form a paste, then use distilled water to dilute this paint. (The reason why I keep mentioning “distilled water” is because hard water contains calcium which reacts with the alkalis in the medium which results in poor drying, etc.)
The other water-soluble wax medium I’ve tried from Kremer is their own version of “Punic wax” called Cerre Stucco soap wax paste made with ammonium tartrate (item# 79230). It’s a very fluid wax soap paste. Since it contains no oil, it’s not really an emulsion. I’ve used it as an isolating layer in conjunction with Kremer’s translucent wax medium by brushing it on broadly on the layer I want to isolate, letting it cure overnight, then heating it with a heat gun the following day. When you first brush it on, it is rather milky and tends to obscure, but the milkiness disappears when the wax dries. Again, use only distilled water if diluting this medium.
I’m still experimenting with both mediums, and so far I’m satisfied with the results….
Kremer’s translucent wax medium either used as a medium or as a binder for dry pigments dries pretty fast like egg tempera. Strokes dry almost instantly and can’t be effectively blended. I use short linear overlapping strokes to simulate values or hues (like one would with pastels) and the strokes stay where they are, so in that way it also handles like egg tempera. The only time I’ve dug holes on the paint surface is when I resumed painting shortly after I blasted it with a heat gun. Apparently the heat softens the surface so it’s best to leave it alone for a few hours after heating to allow the paint surface to cool and re-harden before applying fresh paint.
The other medium, the soap wax paste, applied thinly as an isolating layer theoretically becomes a waterproof barrier once it has hardened and cured. I have not had problems with it as far as lifting thus far. The problem I’ve encountered with it, however, is some beading — when I start a new paint layer. I’m still experimenting with both mediums to see how far I can push them. There are still a lot of variables that I’m still trying to figure out.