Official Luthiers Forum!

Gots me a problem, I do.

I have a guitar almost done, but...

I turns out the truss rod is bust. The nut just spins round round, round round like a record baby, round round, right round.

Theoretically, since the truss rod is not glued in at all, but just nested into a bed of caulking, it should be possible to pull it out and replace it without having to take off the fingerboard.

Is there a developed method for doing this?

Unfortunately, only if you figured yourself one out before you installed your design of truss rod.

Also, it doesn't take much to permanently lock in a truss rod and caulking would be sufficient.

FWIW, here's how I get truss rods out, but the method relies on being able to spin off the adjusting nut (not sure if yours will come off) and spin on the pull bar. Having a neck that unbolts also helps! See the attached pic.

The truss rod design is as per the book, but I install it these days with the adjusting nut only just fully in the hole. In the pic it is extracted a couple of inches (50mm) and you will notice it is also upside down. The reason for that (and for being able to pull it) is so that if you happen to be unfortunate enough to be caught out with a single acting truss rod and a back bowed neck, you can pull the truss rod, flip it, re-insert it, and all is good. Generally, the neck will behave after a couple of months anyway, so you can flip it back the right way for the rest of the guitar's life. To extract the truss rod, all that needs to be done is to spin off the hex socket nut, spin on the similar nut on the end of the pull rod and pull. The washer and the nut on the pull rod are so you can jack it out at least a bit to break any glue bond.

Why not use a double acting rod in the first place, you may well ask. I've got an irrational aversion to truss rod designs that rely on moving parts embedded a long way into a neck, and that covers most double acting truss rod designs. But there is a very neat double acting truss rod design in the 2nd Ed. which has all the motion at the access end and the whole rod can still be pulled in a similar (but not the same) way. However, I still prefer the simplicity of single acting rods.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Just a thought - a large part of that stuff's purpose in life is to stick like sh*t to a blanket and to be a barrier......

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Well, yes, but it isn't actually glue.

We'll see how it goes.

Well, son of a gun...

After removing the tongue and getting the neck off, I was able to get a set of vice grips on the nut.

I put the vicegrips in the vice, and used a stick butted against the neck to gently tap with a rubber mallet away from the vice grips, and...the heat shrink tubing around the rod clung to the truss rod channel, but not the truss rod. The rod itself slipped fairly easily out of it's sleeve which remained intact and in situ.

I then took another rod (after checking functionality) and cut the heat shrink off, and used the mallet to gently force it back exactly where the old one came out.

Surprisingly simple. If it wasn't for the fact that the tongue didn't come off perfectly clean, no one would ever know.

Well done, Ed!

What sort of rod was it?

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

A Chinese two way rod from my old job. First fail out of nearly 200. I guess it broke during fretting somehow. I test them before installing them. My assistant who does the frettingflattened the neck in e normal way, so it was adjusting at one point, but he heard a strange crack and rattle. My gues is a cold weld that severed with the vibrations fro. The fretting hammer.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.