Acetone is great for making quality hash oil. Usually it goes do three successive extractions on your plant material and then filter out the plant matter. Distill off the acetone and you have hash oil. I want to know if you can do the same thing except instead of using plant matter, use some old bubble hash. Old bubble hash gets hard to work with sometimes and a nice oil would be fun. I am no organic chemistry buff, but does the hash being run through acetone effectively dissolve the oils in the solvent and then when the solvent is distilled off the oils/ resin glands that gave the bubble hash its grainy structure would now be in a liquid form. I guess the ultimate question is, is my thought process right? and how much yield would be lost on 3th to 5th bag hash off an 8 bag kit. effectively a 120-73 micron range.
Check the Rec Use Section. There are some stickies that deal with hash. I suggest you check out the "QWISO" hash, as it is the same kind of extraction you're talking about.