Gelcoat/Clear Coat & Styrene

[Decker83]

When I sprayed my deck boat, I used the styrene that the manufacture said to use with their gel coat.. I used a 5% mix..
I sprayed with a pressure pot and a 1.8 tip. With that setup I had no problem with how much gel I could spray..
I sprayed 5 coats at one time.. Then sprayed the PVA..
I also used a kitchen timer and set it at 15 minutes.. I could spray 1 qt in that time and still have time to clean the gun..
I got a really smooth coat and not a lot of orange peel..
Not hard to do but you must move fast and don't stop until your finished spraying..
Good luck..​

 

[Georgesalmon]

FYI, remember that when you thin gel coat you are also thinning the pigments. As WOG said above you need to get to about 20 mils to get it to cure properly. It will shrink from 20 to 16 or less when it hardens and then when you sand it even less. Not thinned gel coat needs at least 12 mils just to cover what is under it, and white is the worst Thinned will have to be even thicker and then there is always problems with sags and runs. If you use a small amount of acetone hold the sprayer about 18" away from the surface and a lot of the acetone will flash before the gel gets to the surface. If there is a lot of porosity in the surface it is from the acetone and called solvent "popping". Gel coat is already formulated to be perfect with the right amount of styene to cross link and polemerise(sp) with thixotropic agents to minimize sags and runs. When you add anything to it its not perfect anymore. There is nothing easy about spraying gel coat repairs.

 

[super_dork]

Ok, so in order to not have to do any thinning (or very little) I've taken your advice. I picked up 2 of the $9.99 HF Purple guns with the 1.4 mm nozzles. I will be returning them after reading some more. I ordered a 2.5 MM one (similar to what sphelps recommended, but from amazon) http://www.amazon.com/gp/product/B001NOU92G?psc=1&redirect=true&ref_=od_aui_detailpages00. It will also spray metal flake (so it says, will cross that bridge later). That way I don't have to pay $20 for a nozzle for a $10 gun. This one from Amazon was just under $40.