by Rick Hill
Q.
Not too many months ago I wrote and asked you a question about conversion varnish. You said that true conversion varnish would not have any lacquer in it. What other questions would one ask to determine if a product that was called a conversion varnish was truly a conversion varnish? What type of facility would a company have to have to use a true conversion varnish?
A.
Another way to determine is to look at the thinner. If Lacquer thinner is recommended, the coating will be lacquer based. If xylol is recommended, you have a better chance of not having lacquer in the product. You can also ask for a sample of their conversion in white, then leave it in a window for a few weeks/months to see if it yellows significantly. Spraying a conversion is as easy as spraying a lacquer. (Conversions are not usually meant to be brush applied.) You need to pay attention to the catalyst ration and the possible recoat windows allowed, but as to a facility, if you have a spray booth and professional quality spray gun you are set. Catalysts in most conversion varnishes are acid-based and will eventually corrode any non-stainless steel spray guns or equipment. If you are thinking of converting, find a local source who can help you with a complete system to use.
Rick Hill is an independent representative and consultant for industrial wood finishes. He has been involved in the woodworking industry for 12 years, and has been known to actually hold, shoot, and clean a spray gun.
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