Tape on truss rods and unwanted vibration

[antonius]

I just noticed that when I play a certain interval (7th fret on E and 7th fret on G string at the same time) on my 1975 4001, I get a horrible resonance or vibration coming from within the neck. I don't think the sound of it gets to the pickups but at low level practice volume it sounds and FEELS horrible. I don't get this playing any other notes (single or chords) anywhere else on the neck. I checked and everything else on the instrument is tight and secure.

I had the rods out recently and cleaned them up, but they didn't have any tape on them and so I put them back in without any tape. My questions are:

1. Would putting some tape on the rods eliminate this resonance problem or does it just solve the problem of rattling rods ( I don't have any rattling)? I guess if tape wouldn't help then do I just try to tune out the resonance with slight adjustments of the rod nuts?

2. Does tape on the rods improve perfomance of the rods in any way - by effectively forcing each half slightly apart, for instance? I had to go to lighter low tension strings as I couldn't get the neck straight with heavier strings despite the rod nuts being as tight as I could get them, and after cleaning up and rethreading the rods. Perhaps the rod channels are too deep or something? I'm happy enough with the neck relief now with the lighter strings but I would be interested to gain any insight.

3. On the old style rods is it simply a case of applying a thin strip of electrical tape all along the inside face of each half of the rods?

Thank you in advance for any information and advice you can offer.

[johnallg]

I just noticed that when I play a certain interval (7th fret on E and 7th fret on G string at the same time) on my 1975 4001, I get a horrible resonance or vibration coming from within the neck. I don't think the sound of it gets to the pickups but at low level practice volume it sounds and FEELS horrible. I don't get this playing any other notes (single or chords) anywhere else on the neck. I checked and everything else on the instrument is tight and secure.

I had the rods out recently and cleaned them up, but they didn't have any tape on them and so I put them back in without any tape. My questions are:

1. Would putting some tape on the rods eliminate this resonance problem or does it just solve the problem of rattling rods ( I don't have any rattling)? I guess if tape wouldn't help then do I just try to tune out the resonance with slight adjustments of the rod nuts?

2. Does tape on the rods improve perfomance of the rods in any way - by effectively forcing each half slightly apart, for instance? I had to go to lighter low tension strings as I couldn't get the neck straight with heavier strings despite the rod nuts being as tight as I could get them, and after cleaning up and rethreading the rods. Perhaps the rod channels are too deep or something? I'm happy enough with the neck relief now with the lighter strings but I would be interested to gain any insight.

3. On the old style rods is it simply a case of applying a thin strip of electrical tape all along the inside face of each half of the rods?

Thank you in advance for any information and advice you can offer.

Antony, Lets see:
1. I believe your resonance problem is also a rattling. I'd make sure the truss nuts are at least snugged up and not leaving the rods loose.

2. Taping the rods doesn't improve the performance, just keeps them from rattling in their channels. We're talking the new style rods here.

3. Yes, the old rods only have the electrical tape between the two folds to prevent rattling to each other. The rods need to move independently in order to work. Your rods are vibrating against the wood, thus the suggestion to snug them up (put in some bowing of the rods to press them against the wood so they can't vibrate.

[antonius]

John,

Thank you for your response. The rod nuts were in fact as tight as I could safely get them so I decided to take out the rods and put some tape on them. When I put them back in again the vibration was still there but then I made a discovery when I accidentally touched the E string with my right hand while applying pressure in various places to see if I could cancel out the vibration. It turned out that the vibration was the E string below the note I was fretting vibrating ever so slightly (so minimally that you couldn't see it moving), and making the lightest of contact with the 1st fret. I guess the solution to this is in raising the groove in the nut slightly with glue. I have had the rods vibrate in the past and it made a similar noise so I guess this is why I didn't suspect the true cause of this problem.

[johnallg]

And there you have it. Dale posted this - if you have an old bakelite nut, file it to make powder and mix with superglue and ill in the slot then refile to the depth you need. If it is a white nut, use baking powder.

[antonius]

Thanks John. That is what I will do. I think I've read too that you can mix charcoal with the glue too. I don't know how I managed in the past before all this help, advice and information was available on the internet.