4 Tips about Spray Guns vs. Cup Guns

130354G830 2.0 HVLP
Spray Gun
Product # 130354 

130295G100-6 Professional Cup Gun
Product # 130295

1. Cup guns will spray gelcoat straight out without having to reduce the gelcoat first.

2. Spray guns depending on the tip size may require reduction with Patch Booster or Duratec.

3. Cup guns are generally used for mold application.

4. Spray guns are generally used for re-finishing parts.

5 Tips on Various Fiberglass Coatings Solvents

1. Acetone is good for cleaning polyesters, but not epoxies.


2. Lacquer Thinner tends to be a good solvent for cleaning surfaces to remove wax and oils.


3. Isopropyl Alcohol 99% (water free) is a mild solvent that is recommended when using Epoxy Table Top Resin and cleaning new epoxy surfaces.


4. Mineral Spirits works well with paint and polyurethane enamel.


5. Styrene reduces polyester, iso and vinyl ester resins for better wood penetration.


4 Tips on Boatyard Polyester Resin

1. Boatyard Polyester Resin may or may not contain wax. If it contains wax, laminates will dry tack-free. If it does not contain wax, the surface will have a tacky feel unless sanding aid is added to the final coat.

2. This is an economical laminating resin for repairs on boats (not recommended for use below the waterline), autos, etc.

3. This a non-spec resin. It is a mix of different types of polyester resins, according to what is manufactured that day. Boatyard resin contains varying ratios of orthopthalic, isophthalic, and low profile resins and should be sanded between cured laminations to enhance the bond.

4. The ideal temperature is at 77°F. Best results for this product can be obtained at temperatures between 70°F and 85°F, in a clean, dry, dust-free environment.