I've been playing around with tri- colour gum. I've got a good yellow, and blue, but struggling with red. I've tried a few brands of alizarin Crimson, as well as red pigment from Guerra (too much grit in it). The results are always washed out look. What have you been using?

. I mail order from Opus for my framing supplies, gum printing and general art-store type stuff. We have almost nothing locally. They've been great to deal with.