B string grabbing at nut?

[dplight]

Last week I noticed that the B string on my C+2 is grabbing just enough to cause the tuning to go flat after a string bend. A little push down on the B string behind the nut brings it back in to tune. With the B string completely untensioned the nut is noticeably to tight when the string is placed into or removed from the string slot. I was temped to grab some sand paper and widen the nut slot first, but thought I'd ask for suggestions before I screw something up. String height is perfect, so I don't want to inadvertantly adjust it. So what to do?

[tom]

does the string make a sound or is pinched when you try to lift straight up? if yes then the slot is too tight. first i would make sure the grove does not have any residue in it. you can clean it out with a gentle razor blade sliding. if after that it's still binding. a slight enlarging would be in order. keeping in mind that you don't need to go deeper, some fine sand paper wrapped around the string might do the trick since it will be bigger than the string it will cut the sides before the bottom. i suspect it will only take a tiny amount, so go slow and re check often.

[dplight]

I'll give the razor blade cleaning a shot first and see how that goes. I don't the nut was this way new (a month or so ago) so it may be that there is some crud in there.

[dplight]

I took a look with a magnifying glass and could see a metalic looking buildup along the sides near the bottom of the string slot. It looks like it probably came off the string as it moved in the nut slot. I didn't have a razor blade handy so I took some 220 grit sand paper and took the metalic looking stuff off. Seems to be staying in tune after bending now.

[tom]

some people use graphite in the nut. i'm not a fan of that as it does build up.

[GuitArtMan]

My favorite nut lube is chap stick - no joke. The stuff is slippery, cheap, can be found just about anywhere (and late night before a gig), one tube lasts forever. I know some guys swear by Big Bends Nut Sauce, but the stuff is gawd awfully expensive. I found a similar product at Radio Shack that was dirt cheap by comparison:

[dplight]

My favorite nut lube is chap stick - no joke. The stuff is slippery, cheap, can be found just about anywhere (and late night before a gig), one tube lasts forever. I know some guys swear by Big Bends Nut Sauce, but the stuff is gawd awfully expensive. I found a similar product at Radio Shack that was dirt cheap by comparison:

I've been playing since 1973 and have never tried any kind of nut lube. Maybe it's time. The problem was caused by some kind of build up in the slot making the string stick. The string kind of snapped in and out of the slot. Maybe some lube would prevent this buildup?