Liquid light on glass - How do I make it stick?

Exactly as the title asks. I'm trying to make liquid light stick to glass plates, but I don't know how to get it to work... Is there some kind of spray-on polyurethane that will be porous enough for it to stick?

Clean the glass well with a good cleaner. There are several threads describing this. I use Dichromate / Sulfuric acid mixture, followed by a distilled water rinse then alchohol / ammonia rinse and then distilled water. Adding a chrome alum hardener to the LL will help it stick to the glass after that. If they are not hard enough and don't stick well, try adding some glyoxal to the LL and then using an additional chrome alum prehardener before developing.

PE

How much Chrome Alum should I add per ML?

Use 10% Chrome Alum at the rate of about 5 ml / 100 ml of LL. Prehardener Chrome Alum hardeners are here on APUG.

PE