When the truss rod is maxed out....

[Slowgypsy]

I had an issue with one of my instruments... it got me to thinking...

When it feels as if the truss rod is maxed out... nut won't go any further, which usually means no more threads left... is it because:

1 - There's no more thread left in the nut, although there's still more thread available on the rod itself.

2 - There's no more thread on the rod, although there's still more thread available inside the nut.

Seems like a simple question, but I was just wondering. I measured the available space inside the truss rod nut in question, and it's 18 turns. Although after about 8 turns it seems to jam up. Which got me wondering if there's just not enough of the threaded part of the truss rod available. Any thoughts?

[62bass]

Originally Posted by Slowgypsy

I had an issue with one of my instruments... it got me to thinking...

When it feels as if the truss rod is maxed out... nut won't go any further, which usually means no more threads left... is it because:

1 - There's no more thread left in the nut, although there's still more thread available on the rod itself.

2 - There's no more thread on the rod, although there's still more thread available inside the nut.

Seems like a simple question, but I was just wondering. I measured the available space inside the truss rod nut in question, and it's 18 turns. Although after about 8 turns it seems to jam up. Which got me wondering if there's just not enough of the threaded part of the truss rod available. Any thoughts?

It more like # 1, but there's no more room in the nut because it's closed at one end. If you need to get it to snug down more you can add a couple washers of the appropriate size over the rod.

[Jim Carr]

Originally Posted by 62bass

It more like # 1, but there's no more room in the nut because it's closed at one end. If you need to get it to snug down more you can add a couple washers of the appropriate size over the rod.

+1

I believe #1 is correct. Besides shimming the nut with a washer or two, you can also use lower tension strings, though washers are cheaper.

I wonder what is the cause of the neck's excess relief? What kind of bass/neck and how old? Defretted?

[Slowgypsy]

Well... in my case it's not reason #1. When I take the truss rod nut off, I can send in a bolt about 18 turns. When I put the nut back on the truss rod, I can only turn it about 8 or 9 turns before it jams up. This leads me to believe that there's simply not enough thread on the truss rod itself.

Yes, the idea of using washers has been much discussed here... and it's a good solution. But I'm trying to get a more compete picture of what's going on here.

And while the thinking on this forum has been that you're running out of thread inside the nut... because it has a closed end... I'm starting to think that's not entirely accurate. That in fact, you're running out of thread on the rod.

Not really sure why this is important, but I'm just trying to get an accurate picture of what's going on with this particular instrument.

The instrument is a mid 90's Fender 62 RI Jazz, original good condition frets, with Thomastik Jazz Flats.

Any more thoughts?

[RMay]

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