Tightening truss rod on high tension bass (8 strings)

makz · #1 12-14-2012, 12:34 AM

Hello all.

I have a Hagstrom HB-8 bass (8 string octave courses) on which I have stripped off the truss rod nut for the second time.

The first time I tried to tighten it, the truss rod barely moved before becoming stripped.

I then replaced it with a new truss rod nut and asked a tech to set it up.

Everything was good until yesterday. I decided that I didn't like the setup the tech did after all.

I said to myself: well, I'm fixing this myself, now I know the loose the strings and pull the neck while tightening the truss rod trick, so it should be easy.

On the first try, the truss rod moved easily. I felt lucky and said to myself: it was easy, I'm sure I can still tight it a bit more. I was wrong. I tried the same trick and after three tries, the truss rod didn't move at all and the truss rod nut started to strip off

The bass plays good, but not great, so I think that it cat take a neck a bit more straight, only if I find a way to tight the truss rod without stripping it again.

I think this is being hard because of the tension that the 8 strings put on the bass.

I have setup my other basses myself, including a Hagstrom HB-4 that is basically the same as this but only has 4 strings and this is the first time (well, the second) that I have this problem.

The next time I try this I'm thinking about removing some strings to release the tension, or maybe I will take it to a pro and ask him to put the neck as straight as I like it, but still I want to know how can I do this myself.

Steveaux · #2 12-14-2012, 03:15 AM

Get the proper wrench.

Nev375 · #3 12-14-2012, 03:46 AM

What year model? (Not that I can help, but I'm curious if this isse is on one of the new Hags or a vintage model like my own.) The neck on my '67 has always been rock solid and has never needed an adjustment ever.

96tbird · #4 12-14-2012, 05:55 AM

If the nut stops turning you have reached the end of the threads. Stop! Put a washer or two in to gain more threads for adjustment.

JTE · #5 12-14-2012, 08:03 AM

Do you pretension the neck by manually moving it and while holding it you turn the nut?

That's the correct way to adjust a truss rod. This way you're moving the neck and then only sniffing the nut instead of expecting the nut to move the wood. It saves you from stripping threads and from compressing the wood.

John

makz · #6 12-14-2012, 10:01 PM

Quote:

Originally Posted by JTE

Do you pretension the neck by manually moving it and while holding it you turn the nut?

That's the correct way to adjust a truss rod. This way you're moving the neck and then only sniffing the nut instead of expecting the nut to move the wood. It saves you from stripping threads and from compressing the wood.

John

Yes, I did that :-(

megafiddle · #7 12-14-2012, 10:21 PM

How many threads on the rod are the nut threads engaging?
How many full turns of the nut are there before the nut starts tensioning?

If the nut is only threading on a couple of turns before becoming tight,
it is not engaging enough threads for maximum strength.

Stilettoprefer · #8 12-15-2012, 10:49 AM

Quote:

Originally Posted by makz

Yes, I did that :-(

Well, either the nut was cross threaded (unlikely if you have a good tech), you didn't pull quite hard enough, or you don't have enough threads in the nut. I know my P needs a really strong pull to get it to back bend.

A proper wrench would be good too, if you don't already use one. try slacking all of the strings completely before doing adjustments, too.