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A friend makes band saw boxes. Gave one to a coworker at Christmas. It sits in full sun light.
The glue lines have darkened a lot. The wood, not so much. No stain, water based poly
She has one out of maple in the same office, but not in full light. No color change
I realize cherry will darken, but why just the glue lines? The underside of the box does not show this
Tite bond glue
Should she be using a finish that has a hi uv block?
I have a photo, but need to upload it
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10-14-2017, 09:12 AM
(This post was last modified: 10-14-2017, 09:19 AM by jteneyck.)
That sort of sounds like he didn't get the glue off the wood around the joints (like what happens if you just wipe the squeeze out with a wet rag and don't do a good job) and it's reacting more quickly to UV than the wood itself. All I can come up with.
A UV absorbing finish, like Kem Aqua Plus or GF's HP Poly will prevent light from affecting the underlying wood, and I imagine anything else, for a long while; not forever, however. I did a cherry box 5 or 6 years ago and it hasn't changed at all, although it does not sit in direct sunlight. Also, realize that if wood sits in direct sunlight long enough it will bleach out, even cherry. Cherry first gets darker but it will eventually turn very pale with enough years of strong sunlight on it. How long that would take with a UV finish on it is unknown to me, and it would be a lot longer than using a non UV absorbing finish or no finish at all.
John
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I thought about the glue being on the wood, but this is a bandsaw box- curved cuts in the block of wood. The squeeze out was cut off
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Maybe the glue ducked into the wood on both sides of the joint. I have to think it's related to the glue somehow.
John
