Heating precatalyzed lacquer

What is the proper temperature to heat precat lacquers to? March 20, 2001

Q.
We are heating Sherwin Precat Lacquer T77F37 in our spray operation. The temperature we run it at is 110 degrees. Is this too hot?

Forum Responses
I did a large job with Guardsman precat lacquer. We were using a finish heater at the time, so we went ahead and used the product like a regular lacquer. After six months, the finish got little cracks in it. Guardsman said that by heating the product, it was made too hard and could not take any stress. I don't know if your product will do the same or not.

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Watch that temperature. I would drop it down to about 100 degrees F. If you have an area in the system that may have a heat spike in it, that is well over 120. If that is the temperature shown at the heater, you should be fine.

Bob Niemeyer, forum technical advisor

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I used to spray SW pre-cat in a lacquer heater and never had any problems. However, there are coatings that are designed to be heated. I love using a lacquer heater. It's an easy way to reduce viscosity without adding solvent. So you get a faster build.

What you have to look out for, if you lower the temp, is the temperature falloff from the tip of the gun every 1" from the surface decreases the temperature very rapidly and if you don't have enough heat to start with, you lose any advantage.