Why does lacquer crack on guitars?
But what causes the checking? As the two names suggest, these cracks are in the finish (paint) of the guitar and are caused by extreme changes in temperature. But this does not mean guitars should not travel, only that they must be allowed to acclimatize gradually.
Does polyurethane lacquer crack?
A lacquer finish is more brittle and prone to cracks than varnish or polyurethane, but the good news is that the cracks are repairable. Unlike varnish or polyurethane, lacquer doesn’t cure after it hardens, which means that you can soften it with fresh lacquer. A single re-coat may be enough to heal some cracking.
Why is my guitar cracking?
This usually happens when the guitar is allowed to dry out, causing the two halves of the top to come unglued at the center seam. Overspraying (spraying over the existing finish) is an option if you just can’t live with the cosmetic imperfection of a crack, but it should be avoided on any vintage guitar.
How do you fix cracked lacquer?
Spray a wet coat of pure lacquer thinner on a surface that has cracks, orange peel or roughness. The thinner will emulsify the surface and the defects should disappear when it hardens again. You can get the same results by spraying a full wet coat of thinned-down lacquer.
What is checking on a guitar finish?
Finish checking refers to the process of finish cracking that occurs over time due to changes in temperature. A majority of luthiers in the current market use razor blades to achieve a finish checking effect.
Why is my lacquer cracking?
Some of the most common mistakes that lead to cracking include applying the finish too thick (common with conversion varnish), using a hard/brittle finish over a softer/flexible finish, or using the wrong finish for the job.
Does lacquer paint crack?
As it ages, lacquer shrinks and cracks. Usually is is worse where it was applied heavier, some of the custom paint jobs years ago were really bad because the heavy application of clearcoats.
Do cracks in a guitar affect the sound?
Hence, when there is a crack in an acoustic guitar, this will affect the way that the sound is transmitted. So what’s the impact? Well usually, cracks will result in less sustain (how long a note can be heard), and less resonance. Cracks still can impact the tone of an electric guitar, but it’s not as big of an issue.