Understanding Truss Rods

[skibum5545]

I have a bass with a maxed out truss rod. I want to fix this problem, naturally enough and here is the advice I was given:

For the neck problem, I would loosen the truss-rod nut all the way, and take it off, if it will come off. I would then find, or make, a washer to fit in on the threaded truss rod. Usually a washer that's about 1/32" thick will do fine. A thicker washer is usually ok, as long as the truss-rod nut will still screw onto the rod. before screwing the nut back on, I would clean it well, then put a little grease on the nut's threads, and a little grease on the edge of the nut that will touch the new washer. I would then screw the nut onto the rod just a little. It should be left loose now. Then I would clamp the neck into a back-bow, with a special set-up of wood blocks and a clamp. You could also have someone hold the bass body firmly against a table top, while you use one hand to push the neck into a back-bow at the headstock. While the neck is being held in a back-bow, tighten the truss-rod nut to the max.

then stop pushing the neck into a back-bow with your hand, or remove the block and clamp set-up, if you used that method to put it into a back-bow.

Here's my question:

Assuming this works, how does it work? How does putting the washer on give you a larger adjustment range? A diagram would help for a headstock access to the truss rod.

Second, assuming the washer thing works:

Okay, so I finish clamping and tightening down the truss rod. I remove it from the clamps, and the truss rod is holding the neck in a back bow. So, if the truss rod is capable of holding the neck in that back bow because its adjustment range is large enough to do so, why not get rid of the clamps, and just crank down the truss rod nut until the neck is in a backbow, and not risk the clamp thing?

Any help is great!

[pickleweaseler]

Assuming this works, how does it work? How does putting the washer on give you a larger adjustment range? A diagram would help for a headstock access to the truss rod.

The washer trick works in cases where the wood around the trussrod nut has been compressed. I don't know if it will work if that isn't the problem.

[soapbarstrat]

You add the washer because the nut screwed on all the way before you got the neck where you wanted. and/or the nut is digging into the wood, and a washer will spread-out the bearing force at least a little more.

Using clamps just makes it easier to get it back-bowed. You're helping the truss-rod do it's job. because the neck has been used to being in a less than optimal position for who knows how long.

Hey, if it's been working for Erlewine all these years, I'm not going to doubt it.

It's worked for me.

The more I work on necks, the more I realize even maple necks sometimes

give-in to string pull awful easily, and the only thing making them playable is a truss-rod working like a dam, holding back the neck from bowing too much with the string-pull. (or tighter fitting frets to stiffen it )

Another thing I wonder about necks with this type of problem, is how the guitar is being stored when not being played. If the guitar is being leaned against the wall, with the headstock touching the wall, that's no good. It's also not good to use a stand where the neck is supported way up near the headstock. I mod (hacksaw) my metal stands so that the neck support is behind where the 13th-14th fret is . I also like the stands that just touch the body and not the neck. I got one of those that hold 5 guitars