Possible Neck Twist

[Rango Blindheart]

Hello all, just received a Gibson Howard Roberts Fusion III which is in lovely condition but it is hitting the frets on the treble side when I play a barred G major (third position).

I have capo'd it at the 12th fret and at the first fret (to remove any effect of how the nut is cut) and measured the relief at the treble and bass E. There is a slight difference, Bass is 0.15 mm and treble is 0.05. What should the tolerances be on measurements like this please?

Compared to my Strat which is exactly the same both sides.

[StefanoGhirardo]

So far, I've found (on about twenty different guitars, with over a hundred measurements in total) a maximum discrepancy of 0.05 mm, so 0.1 seems a bit excessive. However, I've found that on guitars with truss rods that weren't used much, heavy use over a period of time limited or eliminated the discrepancy. On an older guitar, however, especially when tightening, it's important to be very careful and progressive.

[Sigmund451]

No expert here but Id test it out with a straight edge too in order to double check your variance.
It feels a lot different checking opposite strings. Big round strings can test differently than a thin string.

For instance, it can be easier to see the thin string move when barely bumped vs the heavy string not being displaced as much (in terms of percentage) when it gets bumped. Depending on your feeler gauges, a rounded edge can kind of quitly squeeze underneath a curved surface of a string. A string is fine for general use but to diagnose a problem Id use a different tool. So Im guess Im suggesting the possiblity that your amount of variance between top and bottom just might be less than you have measured.

Also, for us mere mortals it can be difficult to tell if its variance in frets or an issue with the neck.

I would also check the other strings too...not just relying on the hopes that the outisde strings are representative of the whole. Depending on the quality of past fretwork , the outside edges could either be uneven. Its easy to over do them as well as under. Anyway, you dont want to make decisions with a limited data set.

The best advice...since it isnt playing right... is to stop by a luthier if you have one.

[Rango Blindheart]

No expert here but Id test it out with a straight edge too in order to double check your variance.
It feels a lot different checking opposite strings. Big round strings can test differently than a thin string.

For instance, it can be easier to see the thin string move when barely bumped vs the heavy string not being displaced as much (in terms of percentage) when it gets bumped. Depending on your feeler gauges, a rounded edge can kind of quitly squeeze underneath a curved surface of a string. A string is fine for general use but to diagnose a problem Id use a different tool. So Im guess Im suggesting the possiblity that your amount of variance between top and bottom just might be less than you have measured.

Also, for us mere mortals it can be difficult to tell if its variance in frets or an issue with the neck.

I would also check the other strings too...not just relying on the hopes that the outisde strings are representative of the whole. Depending on the quality of past fretwork , the outside edges could either be uneven. Its easy to over do them as well as under. Anyway, you dont want to make decisions with a limited data set.

The best advice...since it isnt playing right... is to stop by a luthier if you have one.

I contacted the store and they are happy to arrange a return.

[deacon Mark]

It could be a twist of a bit, or it could be the way the frets are dressed. What you did is fine but to completely check it you need a fret rocker and go over the entire fingerboard and frets. The neck with more relief under the bass side actually make sense and it easily could be more but not twisted as such. Without see and going over the guitar cannot make any judgement. I can say though that if a person owned and there was this twist action, a fret dressing could easily make it play fine. That would in fact be the first move to get the guitar playing correctly.

[Rango Blindheart]

I think with the barre at the third position causing string rattles that aren't present at adjacent frets then the neck or the frets have a bump or a high point somewhere. Paid towards the high end of what they are worth so don't want to have to start paying to get things fixed.

[deacon Mark]

I think with the barre at the third position causing string rattles that aren't present at adjacent frets then the neck or the frets have a bump or a high point somewhere. Paid towards the high end of what they are worth so don't want to have to start paying to get things fixed.

i agree if you are not happy with it and it needs fixed then yes send it back. However, your way of diagnosing with the barre at the 3rd fret is not something any luthier would consider making determinations about the neck twist. But yes, send it back.