Is the foil a good permanent solution? Yes, Locking nuts get shimmed all the time, outside of a bad fret problem, their are two possibilities here, defective locking nut, or nut slot cut too deep, you can replace a bad nut easily, but "uncutting" and recutting the nut slot is going to cost a "FEW" dollars more, so shimming the nut up a few thousandths is just a quick easy fix, not perfect, but it is a fix. I have a question for anyone who has taken a guitar or two to the repair shop, Has the friendly repair guy ever invited you to watch him fix your guitar?
Another case for nut shimming, you buy super cool locking nut guitar with super cool low action, play it 5 years day and night, wear out the frets, get a fret job, and have those new super Mammoth Magnum Ultra high jumbo frets installed, the locking nut is getting shimmed or fret 1 just became the zero fret.


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Pay no attention to the man behind the curtain, He's only fixing your guitar.............