Originally Posted by
koraks
Iirc, the potassium alum in the spice rack is much less effective as a hardener than the chrome alum I usually come across in ingredients lists. I have no experience with potassium alum, but it's something to keep in mind when mixing stuff; you'll likely need much more of the potassium salt than of the chrome salt if that's what's indicated in your formula.
Out of sheer curiosity: what do you need a hardener for? I've never come across a situation myself where I needed one with regular materials; only for gelatin sizing papers for alt processes.
Bookmarks