Taking neck off bass for several weeks: how much should you loosen the truss rod?

[Thunder Pulse]

I'm going to have the neck off of a bass for several weeks or longer and I'd like to know how much I should loosen the truss rod. Thanks.

[202dy]

Originally Posted by Thunder Pulse

I'm going to have the neck off of a bass for several weeks or longer and I'd like to know how much I should loosen the truss rod. Thanks.

Two answers:

1. When the neck is off the body there is no tension on the neck. There fore there should be no compression on the truss rod. Turn the nut until it is loose.

2. The neck will be off for a couple of weeks. It is a different situation than if it were going to off for months or years. Leave it alone. Reinstall and adjust for set up. Don't worry about it.

Ultimately is doesn't matter. Do whichever makes you feel comfortable. Just understand that there is no reason to adjust the truss rod to some "middle point" which would be well nigh onto impossible to calculate anyway.

[walterw]

Yep, probably not a big deal. If weeks turns into months, it might be worth loosening it, at least enough to lose the backbow and be sitting fairly straight.

[4001]

Loosen it all the way to the point where you can turn it and it starts tightening. But don't tighten it.

Just leave it at 'zero'.

[walterw]

I dunno, with some necks that means leaving it in significant upbow.

I'd adjust it straight, wherever that leaves the rod tension.

It seems like problems happen when a neck is bowed significantly one way or the other and then stays that way for a long time. Leaving it straight should avoid any issues.

[Thunder Pulse]

Thanks for the replies. The 'plan' is having it off for a few weeks, but it could end up being longer, I'm not sure. I think I'll loosen it a bit and just keep my eye on it while it's off. Thanks again.

[96tbird]

Meh, I had my neck off for fifteen plus years with no truss loosening and it was fine. I had no idea, oh to be young again! I will add that when I took it off, the bass was already 15 years or so old. LOL Cool dry location is the most important factor I think. IMO.

[Turnaround]

If a couple of weeks might turn into something longer, why not just be safe and take the tension off the rod. May not be necessary but it will be safe.

[96tbird]

Yes. Just to be safe, do it...

[Oren Hudson]

I wouldn't touch it no matter how long it's going to be off. I own numerous basses and have had many of the necks off for many months and sometimes years with no problems. Think about it. When you loosen the rod, what happens? The tension is reduced. What happens when the tension is reduced? You get more "U" shape. Now if that's what you're after, no problem, but most of us usually try ot get rid of most of the "U."

[Syco_bass]

I leave/have necks hanging in my shop for long periods of time. I did not pay attension to a couple of necks that had tension on the rods, when I went to install them, they were permanently back bowed from the tension. Keep in mind that I live in an extremely arrid climate (AZ) now I store them in a cooler/Temp controled area with what ever tension is necessary to keep the neck in a nutrual/straight possition.

[Turnaround]

Originally Posted by Oren Hudson

I wouldn't touch it no matter how long it's going to be off. I own numerous basses and have had many of the necks off for many months and sometimes years with no problems. Think about it. When you loosen the rod, what happens? The tension is reduced. What happens when the tension is reduced? You get more "U" shape. Now if that's what you're after, no problem, but most of us usually try ot get rid of most of the "U."

Think about it. If you leave the tension on it, what do you get? Back bow. Without the string tension the trussrod will force the neck into a back bow - not a big deal in the short term - depending on a number of factors. But removing the tension means the neck will have one less factor working against it.

[96tbird]

Originally Posted by Turnaround

Think about it. If you leave the tension on it, what do you get? Back bow. Without the string tension the trussrod will force the neck into a back bow - not a big deal in the short term - depending on a number of factors. But removing the tension means the neck will have one less factor working against it.

I have never seen backbow with my necks unstrung. they are straight. You may or may not get backbow if you normally have relief when strung. It would be dependant on the relief you begin with. Anecdotal, non-professional observation but true IME.

[Turnaround]

Think of it this way.

Necks are manufactured FLAT. The truss rod is there so that you can control the amount of bow caused by string tension by adding a compensating tension in the opposite direction in the neck. Having added that tension, when you remove the strings, the rod will pull the neck into backbow.

Or if you don't understand that, try this - a tug of war. If both sides are pulling equally and then one side stops pulling, what happens? Does the first side stay where they are or do they end up going backward?

[walterw]

Originally Posted by 96tbird

I have never seen backbow with my necks unstrung.

i've never seen a properly adjusted wood neck that wasn't!

(by "properly", i mean just about straight when strung.)

[96tbird]

When it comes to relief, there is no properly. It's players taste. I prefer a thin picks worth of relief at the 8th fret. Unstrung my necks are flat.
Anyway, I guess this discussion is adding confusion. Now, I would loosen the truss, I merely said I didn't on one neck and left it for years. Just luck I know.

[walterw]

a "thin pick's worth" is not super up-bowed or anything. (i like it a little straighter, but we're in the same ballpark here.) usually necks at that relief will have some backbow when un-strung.