Truss Rod Help

[PURPOLARIS]

My truss rod seems to be slipping, if that's the right word. It works fine when the neck is off the guitar and it bows the neck both ways when I adjust the screw but when it's on the guitar, no matter what I do it bows too much and the action is too high. When I adjust the nut the neck straightens for a bit then bows again. Is there a simple fix or explanation for this or should I get a new neck ? I would rather fix it as I really like this guitar. Any info would be greatly appreciated.

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[GreeneKing]

I've never heard of a truss rod 'slipping' like this.

You could try a thin card shim between the neck and the bass in the neck pocket, tucked towards the bridge end of the pocket. It might give the trussrod a hand?

It's what I'd do anyway and may be worth a try before more drastic repair action is taken.

Peter

[PURPOLARIS]

[quote name='GreeneKing' post='559410' date='Aug 3 2009, 05:00 PM']I've never heard of a truss rod 'slipping' like this.

You could try a thin card shim between the neck and the bass in the neck pocket, tucked towards the bridge end of the pocket. It might give the trussrod a hand?

It's what I'd do anyway and may be worth a try before more drastic repair action is taken.

Peter[/quote]


I have done this and it makes the Bass playable for me but I would like the action a bit lower and can't do this without the neck straightening a bit. It seems strange that it works fine when there's no tension from the strings but is too weak to resist the tension when it's applied.

[rslaing]

Take it to somebody who knows what they are doing...............

[PURPOLARIS]

[quote name='rslaing' post='559490' date='Aug 3 2009, 06:29 PM']Take it to somebody who knows what they are doing...............[/quote]


I know what I'm doing except I've never come across this problem before and I have had a lot of guitars (over 100)come and go. I've never come across this problem before. "Take it to somebody who knows what they are doing..............." doesn't really fall into the simple fix or new neck category which was my original question but thanks for trying.

[rslaing]

[quote name='PURPOLARIS' post='559500' date='Aug 3 2009, 06:37 PM']I know what I'm doing except I've never come across this problem before and I have had a lot of guitars (over 100)come and go. I've never come across this problem before. "Take it to somebody who knows what they are doing..............." doesn't really fall into the simple fix or new neck category which was my original question but thanks for trying.[/quote]

Which is why you need to take it to someone who is a specialist and knows what they are doing? It wasn't meant as a criticism.

It needs to go to an expert. Then you can take his advice and either have it fixed or take his advice on the best way forward

[PURPOLARIS]

[quote name='rslaing' post='559535' date='Aug 3 2009, 07:14 PM']Which is why you need to take it to someone who is a specialist and knows what they are doing? It wasn't meant as a criticism.

It needs to go to an expert. Then you can take his advice and either have it fixed or take his advice on the best way forward[/quote]


No criticism taken, it just wasn't a very helpful answer that you gave me. It's easy enough for me to think of that myself :-)

I'm looking for someone on here that's possibly come across this problem before and how it was rectified, after all it's what this site is for, sharing information etc. There are a lot of experts on this site that might be able to help instead of me waiting until Saturday at the earliest to get my guitar to a music shop.

In a nutshell with no string tension the truss rod works fine, under string tension the neck won't straighten, it's as if the truss rod has weakened and isn't strong enough to resist the tension of the strings. I have put it into negative bow before attaching it back to the body and it still bows too much when the strings are tuned. If it means a new truss rod it means a new neck. That is the cheaper option. Simple

[rslaing]

[quote name='PURPOLARIS' post='559550' date='Aug 3 2009, 07:28 PM']No criticism taken, it just wasn't a very helpful answer that you gave me. It's easy enough for me to think of that myself :-)

I'm looking for someone on here that's possibly come across this problem before and how it was rectified, after all it's what this site is for, sharing information etc. There are a lot of experts on this site that might be able to help instead of me waiting until Saturday at the earliest to get my guitar to a music shop.

In a nutshell with no string tension the truss rod works fine, under string tension the neck won't straighten, it's as if the truss rod has weakened and isn't strong enough to resist the tension of the strings. I have put it into negative bow before attaching it back to the body and it still bows too much when the strings are tuned. If it means a new truss rod it means a new neck. That is the cheaper option. Simple[/quote]

Why don't you PM the Bassdoc? He might be able to tell you what is causing the problem.

He knows everything.

[skankdelvar]

Not run into this before. Sounds like maybe:

1) The truss rod nut is wound so far in, it's compressing into the wood when under tension. Further tension from strings compresses wood even more - neck bows. Could try dropping a couple of washers in to act as spacers between the nut and the end of the truss rod channel.

2) The rod nut screw threads are stripped / stripping - just enough to let you tighten it yet still let the neck pull back under tension.

Faint possibility - screw holes in neck heel are wearing wide - the neck securing screws are then slightly pulling out of the neck, allowing it to pull upwards? Even the proverbial 'thickness of a bit of card' would be enough - akin to front shimming the neck? Worth establishing that your screwholes are tight.

Either way, it's most likely a truss rod issue and shimming probably won't help.

No offence intended, but I've found if I can't diagnose the problem myself, I probably can't fix it myself. A trip to a luthier would probably be cheaper than a new neck.

Good luck.

Edited August 3, 2009 by skankdelvar

[PURPOLARIS]

[quote name='skankdelvar' post='559593' date='Aug 3 2009, 08:11 PM']Not run into this before. Sounds like maybe:

1) The truss rod nut is wound so far in, it's compressing into the wood when under tension. Further tension from strings compresses wood even more - neck bows. Could try dropping a couple of washers in to act as spacers between the nut and the end of the truss rod channel.

2) The rod nut screw threads are stripped / stripping - just enough to let you tighten it yet still let the neck pull back under tension.

Faint possibility - the neck securing screws are slightly pulling out of the neck, allowing it to pull upwards? Even the proverbial 'thickness of a bit of card' would be enough - akin to front shimming the neck? Worth establishing that your screwholes are tight.

Either way, it's most likely a truss rod issue and shimming probably won't help.

No offence intended, but if you can't diagnose the problem yourself, you probably can't fix it yourself. A trip to a luthier would probably be cheaper than a new neck.

Good luck.[/quote]

Thanks I'll try the washers trick. From what I believe it's cheaper to replace the neck than to replace the truss rod due to the amount of work involved. It's not an expensive guitar or my main guitar so I'll probably stick a 50 - 80 quid neck on if I can't solve it. I'm pretty sure a luthier would cost more than that to fix it.

[mrcrow]

it sounds like its stripped and slips under tension

what part could be gone i dont know ..

[Mr.T]

[quote name='mrcrow' post='559651' date='Aug 3 2009, 09:03 PM']it sounds like its stripped and slips under tension[/quote]

+1... Sounds like a stripped thread.

[BigRedX]

I can remember reading that ideally the nut should be made of a softer material than the truss-rod so if the thread strips it will be on the most easily replaced part. Of course whether this applies in practice on a mass-produced instrument is another matter.

[MoonBassAlpha]

When you put negative relief in the neck, string it (relief goes too far positive), when you take it off again, is the negative relief still there? I think that if it isn't, it is likely the nut has slipped, ie stripped. If it is the nut portion, not the rod then a new nut alone might fix the prob.
You aren't using massively heavy strings are you?
Hope this is some help.
Jules

[mrcrow]

[quote name='BigRedX' post='560065' date='Aug 4 2009, 11:53 AM']I can remember reading that ideally the nut should be made of a softer material than the truss-rod so if the thread strips it will be on the most easily replaced part. Of course whether this applies in practice on a mass-produced instrument is another matter.[/quote]

the most easiest to replace component...from an access point of view should be the softest in general terms
if the nut is easy to get out...then ok
i often wondered how they got the truss rod etc in there anyway....i thought the fretboard would need to come off

[PURPOLARIS]

[quote name='mrcrow' post='562230' date='Aug 6 2009, 08:36 PM']the most easiest to replace component...from an access point of view should be the softest in general terms
if the nut is easy to get out...then ok
i often wondered how they got the truss rod etc in there anyway....i thought the fretboard would need to come off[/quote]

I'll order a new nut and see if that solves the problem. The nut comes out fairly easily so it's no bother. As it is, I've got the bass playable by shimming the neck but the action is higher than I'd like it so I'd really like to get it fixed.