#1
So I got a Epiphone SG (1966 G-400 Pro model) that's a bit difficult to tune. Sometimes as I'm tuning up the string would just go immediately sharp just before the note. It happens most often in the G string, sometimes there's this "pinging" noise just before it gets in tune then it goes sharp.
Yup.
#2
The string has cut nicks in the nut slot that are catching the string. Fold small pieces of fine sandpapers and carefully smooth out the slot. Don’t make it bigger, just smooth it out.
#3
It's the nut. as jpnyc said, you need to widen the nut slots. There are a million and one different ways to do this. A great and very cheap set of tools for doing this are welding torch tip cleaners used for cleaning oxy-acetylene torches. They're basically very small needle files that come in a variety of sizes that are perfect for nut slots. They're only a couple bucks for a full set.

Then after you're done, write a pencil into each slot.
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#5
Quote by T00DEEPBLUE
It's the nut. as jpnyc said, you need to widen the nut slots.


No! Wide nut slots are bad! Wide nut slots cause the string to slide around during bends and the string ends up popping in and out of the grooves it creates when it’s being tuned. Nut slots should only be widened to compensate for strings significantly heavier than the factory strings.
#6
Quote by jpnyc
No! Wide nut slots are bad! Wide nut slots cause the string to slide around during bends and the string ends up popping in and out of the grooves it creates when it’s being tuned. Nut slots should only be widened to compensate for strings significantly heavier than the factory strings.

The nut slots would have to be absolutely massive (relative to the strings themselves) for that to have a significant effect. I'm not telling TS to turn the nut slots into chasms. I'm telling him to widen the slots enough that the string doesn't get pinched. By smoothing out the nut slots, you effectively widen them.
Roses are red
Violets are blue
Omae wa mou
Shindeiru



Quote by Axelfox
Reeeeeeeeeeeeeeee
Last edited by T00DEEPBLUE at Sep 8, 2014,
#7
If you widen the nut slots very slightly, should be no problem. You don't want them wide enough to turn grandpa's Cadillac around in of course...

The welding tip cleaner trick should work, pick the one that fits the slot and just open it up a tiny bit. Try not to cut it deeper, then you have the risk of getting it too deep and creating fret buzz at the first couple of frets. It shouldn't take much at at all.

Some graphite from a #2 pencil might help too, that will lubricate the slot so the string is not as likely to bind. I use it in my tremolo guitars every time I change strings, helps them stay in tune better when using the tremolo arm.
Hmmm...I wonder what this button does...