Why do old Fender headstocks.....

[Fishin'Musician]

turn orange? I see this kind of thing a lot, where the headstock face turns orange but the back and sides of the headstock, the back of the neck, and the fingerboard don't. My '71 Tele is like this, as is my '73 P bass.
http://i7.photobucket.com/albums/y274/gglaesemann/orangeheadstock.jpg

[whaiyun]

I think it has to do with UV rays hitting the finish and causing it to darken, but the board n neck don't because of continual play? That's my best guess

[railfanespee]

I believe the effect is due to the fact that the front of the headstock is finished in nitro and the rest of the neck is in poly. Fender switched to thick poly finishes around '68, and one of the "advantages" of poly is that it is much more resistant to wearing. But if memory serves, the headstock decals Fender was using didn't get along with poly finishes, so the front of the headstock was finished in nitro. Nitro is much more prone to aging, yellowing, and checking, which explains the color difference. Eventually (not sure of the year though) the process changed and all of the neck could be finished in poly. Look at an early American Standard, for example, and the headstock face will be just as aged as the rest of the neck (in other words, barely yellowed at all).

[billywade]

^this

I've heard it referred to as a "bar tan".

[DB Cooper]

I just read this article on Fender paint (http://home.provide.net/%7Ecfh/fenderc.html) last night...wow is all I can say! Highly recommended if you really want the scoop!

[supa-fuzz]

^Good reference, been to that site before, wouldn't say it is the entire gospel, always inconsistencies with vintage instruments, but good rule of thumb info.