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Hex Nut Stripped on Bass Guitar

Q: I recently purchased a used 5-string Cort Curbow Bass Guitar and the neck has a little to much relief in it (forward bow). I knew what would have to be done so I removed the truss rod cover and proceeded to find the correct allen wrench to fit and come to find out someone most likely has already been trying to adjust the truss rod and have stripped the hole and it is rounded off inside and I have had no luck in finding away to tighten the truss rod. If you would and don't mind, could you maybe suggest any possible remedies for such a problem? I really like this guitar and would love to be able to repair if expense is not to far out of reach. Thanks Kindly, Jeff

A: Go to your local auto parts store and get the next size up Allen wrench and a 12" flat bastard file. File the new wrench into a taper from very slightly larger than the old one at the end up to the new size about a 1/4" from the end. Then jam it into the hole until it grips.
Now, here is the essence! The nut is stripped because something stopped it's foreword progress! Somebody tried to make it tighter and stripped the hole. Use your new minimal grip in the hole to back the nut off. Righty tighty, lefty loosey, turn it left and take it off. Inspect the nut carefully, shining bright light into the hole. It might only be stripped near the end and a custom filed wrench, that went all the way in, might be the solution. The sweetest solution would be to be able to buy a new nut. Sadly there are only four or five replacement nuts available, and they tend to not fit whatever guitar you are working on. The first step would be to go to Stew- Mac and order all the nuts that look like they might be the right one. The next would be to go to a good hardware store and get creative with nuts and spacers and washers etc.
If you are lucky, the nut stopped working because it came to the end of the truss rod threads. Find, or make, washers to stack on the rod, giving the nut more threads to pull on. If you are unlucky the nut may be at the end of the threads because the rod pulled out of it's seating pin at the other end. Or, the rod broke in the middle or there is some other inaccessible deformity in the rod. Very generally, modern truss rods work well and never break, so look for simple solutions first. The Allen wrench that came with the guitar may have fit poorly and the hole might not be completely shot. You might also be able to cut a slot in the end of the nut and tighten it with a screw driver.
Stare at it, go to bed thinking about it, put one hand behind the neck and one on the peghead and bend the neck straight and see what happens at the rod. The rod nut should move smoothly and easily. If you don't figure out why it doesn't, your new nut will strip too.

Steve Mason

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