Truss rod rattle

RelayDuzzy

Has anyone here dealt with this problem before?  I've been noticing a weird kind of buzzing at certain frets, actually down to specific notes in different places along the neck - mainly the F and G notes. After a lot of checking to make sure it's not down to fret levels/action/neck curve, I've come to the conclusion that it's the truss rod.  I reckon it may be a bit loose inside, and the frequency of some notes coincide with its own natural frequency, and cause it to vibrate when plucked.  It's a bit of pseudo scientific guess work on my part, but that's what I reckon!  I did some searches on the internet, and the one solution I came across was dripping some hot wax into the channel by drilling a hole through one of the fret markers and warming up the truss rod with the use of a solder iron.  Anyone tried something like this before or other solutions?

SteveRobinson

What make and model of guitar are you talking about? 

FelineGuitars

Yup - injecting chair doctor glue that swells the wood down the truss rod channel 

Removing a fret and drilling two carefully placed holes at the edges of the truss rod channel and using a syringe with a blunt needle to inject silicone (like the bath sealant type)around the rod

BillDL

I realise this is probably obvious and most likely has been considered, but if the truss rod isn't being used to counteract string tension it would be worthwhile ensuring that the nut is at least snugged up without actually tightening it enough to move the neck.

ICBM

BillDL said:

I realise this is probably obvious and most likely has been considered, but if the truss rod isn't being used to counteract string tension it would be worthwhile ensuring that the nut is at least snugged up without actually tightening it enough to move the neck.

This. The very first thing to try is tightening the rod slightly. Even if the relief is perfect, you can usually move the rod a little without affecting it much, and that’s sometimes enough to cure a rattle.

Barney

ICBM said:

BillDL said:

I realise this is probably obvious and most likely has been considered, but if the truss rod isn't being used to counteract string tension it would be worthwhile ensuring that the nut is at least snugged up without actually tightening it enough to move the neck.

This. The very first thing to try is tightening the rod slightly. Even if the relief is perfect, you can usually move the rod a little without affecting it much, and that’s sometimes enough to cure a rattle.

I had exactly the same problem and this is what done and it sorted it 

WezV

yeah, often taking the slack out the rod can cure a buzz, but some do remain after that and need a little more work

you can also use wax (heat the rod gently so it coats it), or thinned wood glue put down from the adjustment on some rods.

Benm39

Can't help thinking there should be a song/ tune called the Truss Rod Rattle...

RelayDuzzy

I forgot to add, this is a guitar I made with help from a guitar maker, so allowance for some amateur crafting is needed! 

The relief is already exactly as I wanted it, so I didn't want to adjust the truss rod further, but I will try turning it a smidge to see if it helps.  Having said that, I picked up the guitar this morning, and the weird rattle is not there.  So looks like expansion/contraction of the wood or rod due to the temperature is a factor.  Next time it happens I'll adjust the rod to see if it helps.  Better to try the non-invasive approach before doing neck surgery.

Roland

RelayDuzzy said:

... looks like expansion/contraction of the wood or rod due to the temperature is a factor ...

Also, don’t discount humidity changes which also cause wood to swell or shrink.