jfrog said:
Then I had to perform a repair on it and removed the pickguard. I couldn't believe the difference between the color of the finish under the pickguard and the exposed finish. Those years of exposure to UV rays coming through the window had really faded the finish, although I hadn't realized it was happening.
This happens to some degree even if you keep it in the case. It is not a big deal, unless you have a pristine old sunburst. Most of those are already seriously faded, so if you have one which is not, people actually care.
Myself, I have about 15 guitars or so, and I keep them all hanging on the wall. Partially this is because it is conductive to playing, partially because I like them as decoration (they look cool), and partially it is because I do not have cases for them all (the cobblers children never have shoes and all). All of my guitars where made by me or my father (mostly me, early instruments which I did not feel were up to the standards I want on instruments I sell). We have a humidifier on our furnace which can, during the winter, if I push it, keep the house at a relative humidity of about 35%, which is not near enough. The room with the guitars has another humidifier which puts out about 20 gallons a day, during the really dry parts of the year, which barely keeps the humidity in the acceptable range of 45%-55%. And only if I change the filters about twice as often as they recommend. I check my two hygrometers every day during the winter. During the summer, at least if you don't live in a desert, humidity is not an issue. Basically, you need to worry about humidity only if you live in the desert, or you are heating your house. Up here in Minnesota, the humidity inside of an unhumidified house, during the winter, gets dryer than Death Valley. Not a good thing, at all.
Aside from issues of humidity, the only real major concern for storing guitars is heat. If they get too hot, the glue can soften and start to creep. By too hot, I mean anything over about 105 degrees farenheight. It doesn't really start to loosen until somewhere between 110 and 115, but why risk it. By the way, your car easily gets that hot, in about 15 minutes, in the summer, if left sitting in the sun.
For long term storage of your guitars, what we recommend is that you completely loosen the strings, and keep them in the cases. Loosening the strings relieves a lot of tension, which is just a good idea anyway, and if the guitar gets too hot, this will help keep the glue joints from loosening.
Light
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