The kids and I tried Kool-Aid dyeing last weekend (LB Fishermen's Wool), used store-brand raspberry for the red, grape for the purple, Kelly Green Wilton dye for the green, and some similar type powdered food dye for the blue. It's all a bit INTENSE, I may tone down the whole thing with a packet or two of black cherry! LOL I think it's about 400 yards altogether. The grape/purple is a bit blotchy/uneven, probably didn't stir it enough, but doesn't bug me. Kind of used this technique...
It was funny because my daughter and I were unwinding it into a large hank and were using two chairs but as we were winding it around the chairs, the hank became saggier and saggier, and then I realized the chairs were being pulled closer together as we wound the yarn around them (they had been about 5-6 feet apart). So then we used the legs of the kitchen table because I KNEW those wouldn't be moving.
I haven't wound it into a REAL hank yet since I may redye it. I'm thinking I'll try a felted bag with it.