FAQ - Why are there air bubbles in my UV coating?
UV curable finishing is a very unique process and there is a slight learning curve when switching from conventional coatings. Our UV coatings are all manufactured to be thixotropic, meaning that they are a bit thick under normal conditions. As the spray gun is activated, it causes the coating to get agitated and thin out a bit, which helps the flow out of air bubbles and allows for leveling. Within seconds of application to the substrate it thickens back up to help prevent sheeting or drips when applied. The viscosity and thixotropic properties have been specifically manufactured with the customer in mind, so that you can use it straight from the container with no mixing.
Although ultraviolet coatings can be applied by brush, the best method of application is by spray for guitars, furniture, general purpose, and ultra resistant for concrete and stone.
Temperature affects viscosity as well. If you choose to brush, you may want to warm the wood slightly with a heat gun and apply a thin application of 2 mils at a time. Do not apply when ambient temperature is < 60 degrees F. Some UV coating fluid temperatures should be between 70 degrees and 100 degrees F.
Agitators have been known to work for some customers that choose to use a brush applicator; This is a machine that vibrates. You can put your smaller UV coating into a bowl and place the bowl on the agitator while dipping your brush in. Afterwards, remove the bowl from the agitator while applying the UV coating. Repeat as necessary.Application Equipment Recommendations:
Spray Gun/tip Options:
- Graco Compliant with HVLP Air Cap with 0.030 tip, 10-15 PSI fluid pressure, 30 PSI atomizing pressure
- Binks HVLP - #92 tip (0.034"), #97P air cap, 10 PSI fluid pressure, 45 psi atomizing pressure