Adrio wrote:
my gel coat supply guy sold me an additive that they call "air dry". This allowed me to economize as you suggested as I just added that to the last coat so that it would firm up. The previous coats were just straight gel coat and as you say they remained tacky. I don't know what the chemical was in the "air dry" but he calls his top coat gel coat "waxed gel coat" and the stuff I bought he called "unwaxed gel coat". Somehow I doubt it is simple wax but I can say that when the "air dry" came in contact with acetone the "air dry" sure started to look like wax and I had to agitate things very vigorously in order to mix it all together.
The air dry stuff actually has a wax in it. You can buy the wax additive separately so you can use the same can of polyester resin for laminating and then add wax to the last batch for air curing the top coat.
As far as coloring the scratches (or a whole batch of gelcoat), you can get coloring agents from
various dealers that can be added to gelcoat, polyester, epoxy, fillers, Bondo, etc., etc. You'll need to experiment to find the right color mix.
Wow- check out the videos on gelcoat and structural repair (at the link above)!!!! Everything you always wanted to know about repairing fiberglass hulls.
Unfortunately, they only briefly mention "air inhibited gelcoat" and don't go into the differences, wax additive, etc.