I talked with the System3 folks about this because I liked the idea of being able to thin it out more regardless of working temps. They said 'NO NO, don't do that' - part of which may not apply to you. Their concerns seemed to be 2:

1. On bare wood, the acetone would soak into the wood, not be able to evaporate, and weaken the wood. I guess if you were doing a 'top coat' this would not apply

2. According to the tech, most non reagent grade acetone is recycled and not that pure. This would leave some sort of residue - possibly yucky.

Their bottom line to me was - 'you are on your own' if you do that.

: Thought I would experiment a little. I Sanded my System Three epoxy down on a
: S&G recently finished. I then rubed on a very thin coat of Thined epoxy to
: fill in all the scratches from sanding. Now I wonder how long I should let
: the thin coat of epoxy cure before I put my Z Spar Flagship varnish on it.
: I can't find an answer in the System Three Epoxy book, so I thought I
: would ask here since there is a lot of nice people with a lot of
: experience here. Has anyone done anything similar? It seems to work and
: the boat looks good.