Gelcoat Gun
Choosing the right tool for the job is paramount to your success. Not all gelcoat guns are equal. Consider the size of the job before you purchase a gelcoat gun. Fiberglass gelocoat repair can be accomplished quite nicely using a cup style gun. These gelcoat guns typically use a quart sized replaceable cup. With this type of gun cleanups are a snap.
For bigger jobs many professional grade sprayers add the convenience of external mixing and adjustable spray angles to insure proper mix of catalyst with resin/gelcoat. These gelcoat guns tend to be a bit more expensive but if you have a big job in front of you the added expense pays for itself. All Gelcoat dump spray guns require an air compressor that can output between 60-100 psi. For the most efficient use of the gun, always make a careful check that all parts are the proper size and type, and are in perfect working order before operating. In order to assure the least amount of contamination of the Gel coat, moisture and oil traps should be installed and drained daily (minimum) on all air lines at the spray booth. Traps must be installed on the lines at least 25 feet away from the air compressor. Do not even think about spraying below 65 degrees F or over 80. If you live in a warm climate and you have to work in temps above 80 degrees you can switch to a slower kicking catalyst, and mix in the lower end, say 2 percent.
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