Acetone has no inherent moisture. It evaporates almost totally.

Anything that has a water base is BAD for epoxy. (not positive about methanol). It screws with the curing and the resin doesn't cure as hard and sandable. I have used denatured alcohol with decent results as well, but nothing like acetone. It is the best I have ever found that leaves a hard sandable cure.

Back to it yes everyone has thier own methods and everybody has theories. The one constant I have found as far as overall weight reduction is thinning the resin....that one is a must on a plane this size. Whatever the weight ends up being with thinned resin, you can add at least 60% more (if you're GOOD) and usually a lot more if you DON'T thin it. Plus it tends to set too fast not leaving enough working time, getting thicker which just compounds the problem even more...like a snowball effect.

If you cut it somewhere bewteen Dean's number and mine (it's probably very close as acetone doesn't weigh nearly as much as resin) that alone makes a world of difference, and the pot life of the mixture is hours, not minutes. However since it evaporates, it doesn't really effect the final cure time. Although I use the fast set hardener, using the 206 MAY require a little more cure time before sanding. You'll know. If you sand it and it's hard to sand, it's not ready. If it just comes off like fine powder, it's cured enough.

-Mike

Edit: oops sorry Dean