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will varnish check the same as laquer when warmed to quickly from the cold?

just a simple yes or no, anybody?

If by varnish you mean polyurethane, then no. Poly is fairly flexible. I'm not too sure about water based poly, though.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

The problem is that there are too many variables to answer the question as posed. 'Varnish' is a whole family of things; reactive finishes, usually based on an oil and a resin, that harden by polymerization in the presence of air (traditional varnishes) or water vapor (polyurethane). 'Spar' varnishes, that have a high proportion of oil in them, are very flexible and unlikely to crack, while 'rubbing' varnishes tend to be more brittle. Much will also depend on how the finish is applied, how thick it is, and whether there is some sort of undercoat or sealer present, and what that is. Given enough provocation, even the wise will crack....





sorry....

thank you

As an example, my first classical about 50 years ago was a Hagstrom Espana. Driving to a lesson in MInnesota with the heater barey working, the guitar got very cold. Upon arriving at the lesson, I opened the case and the finished crackled as I watched.