It works, eventually. I started soaking my Copal back in September. I ground mine first, then soaked in 150 proof Everclear. It is still soaking, having dissolved around 75% of the Copal. I keep it in a sunny window and shake it several times a day. I did make a double-batch, so that might explain the long soaking time. At this rate, it'll be ready in a month or so. It just takes time.

Regards
Ken

I prefer wood to plastic, leather to nylon, waxed cotton to Gore-Tex, and split bamboo to graphite.