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fretboard rise at the neck joint

mcontour

Supporting Member
Apr 27, 2008
677
644
Happy Valley, Oregon
Hi Folks,

I am unable to get the action as low as desired on my G&L L2K due to a rise in the fretboard at the neck joint. I'm not talking about any kind of breakage or warping.

Is this a common issue?

My trusted repair shop tells me that I need to defret the neck, plane the fretboard, and reinstall new frets. This sounds kinda severe to me. Anyone gone through this before with a successful outcome?

Thanks.

Michael
 
Hi Folks,

I am unable to get the action as low as desired on my G&L L2K due to a rise in the fretboard at the neck joint. I'm not talking about any kind of breakage or warping.

Is this a common issue?

My trusted repair shop tells me that I need to defret the neck, plane the fretboard, and reinstall new frets. This sounds kinda severe to me. Anyone gone through this before with a successful outcome?

Thanks.

Michael

It's a common condition, sometimes referred to as "ski jump". Essentially the neck starts to bend right where the body ends. The only way to "cure" the condition exactly what you've been told. On the brighter side, this condition usually happens to instruments with some age to them, and when properly fixed is usually permanent.

Happened to my Fender AV 62 RI Jazz. Got it fixed and that instrument became much better than it was. A very happy ending.
 
Something to try while you decide...

I've used a "reverse" shim to make some ski jumps more playable. The shim is placed at the headstock end of the neckpocket. You'll have to remove any other shim or microtilt adjustment and adjust the saddles.

If the saddles don't go low enough you can try a flat full neckpocket shim (in conjunction with the reverse shim) to raise the neck heel.

Afterwards I do a general setup with trussrod adjust.
 
you could just get the frets leveled without re-frettng, but you might end up with a paper-thin last fret.

+1

If the hump is small enough, a fret leveling will do the trick. But before taking the last few frets down to nothing, a good tech will recommend at least a partial re-fret and planing.

I also had a tech take almost all the relief out of the neck, perform a slight fret leveling, and the hump disappeared. Kind of the opposite of the shim theory, but it worked.
 
Please explain how fret levelling can be the opposite of shimming.

I didn't say fret leveling was the opposite of shimming. I said that removing much of the neck relief was the opposite of the "reverse shim" outlined above by mongo2. As the neck gets flatter, the hump becomes less pronounced. Combined with a fret level, this can cure the issue on some necks.
 
you could just get the frets leveled without re-frettng, but you might end up with a paper-thin last fret.

This would be my first choice as I rarely venture beyond the 12th fret. The cost is realistic as well. A reverse-shimmed neck with wonky relief will still have wonky relief although in a different planar relationship with the strings and body. Think of it in these terms: the "lift" involves roughly 1/5-1/6 of the neck so we reverse-shim to establish a quasi-normal posture of that portion with the body / string profile. That action, in turn, throws the remaining 80% out of whack. What do we do to compensate? We tweak the truss rod to straighten out the balance of the fingerboard. Problem is that a properly installed trussrod has a more profound effect in the region of the 7th-8th fret and virtually none near the lift. Sidenote: this is one of the better reasons to check relief from the 1st to 17th fret instead of the 22nd...it removes the heel from contention. In some cases, once relief compensation is performed, you'll find segmental faux-relief still exists from 17-22 (should be flat) when assessed with a straightedge, with the balance of the fretboard threatening to form the dreaded "S" curve.

Riis
 
This would be my first choice as I rarely venture beyond the 12th fret. The cost is realistic as well. A reverse-shimmed neck with wonky relief will still have wonky relief although in a different planar relationship with the strings and body. Think of it in these terms: the "lift" involves roughly 1/5-1/6 of the neck so we reverse-shim to establish a quasi-normal posture of that portion with the body / string profile. That action, in turn, throws the remaining 80% out of whack. What do we do to compensate? We tweak the truss rod to straighten out the balance of the fingerboard. Problem is that a properly installed trussrod has a more profound effect in the region of the 7th-8th fret and virtually none near the lift. Sidenote: this is one of the better reasons to check relief from the 1st to 17th fret instead of the 22nd...it removes the heel from contention. In some cases, once relief compensation is performed, you'll find segmental faux-relief still exists from 17-22 (should be flat) when assessed with a straightedge, with the balance of the fretboard threatening to form the dreaded "S" curve.

Riis

Agreed, entirely
 
Not sure where you are at, but heard this can be due to moisture getting in through the neck screws and swelling the wood of the heal forcing the ski bump. Have always put in a few drops of varnish in each neck screw hole to delay the process in my humid enviroment. Agree a defret and planing the only real way to cure once the swelling is done.
David
 
Not sure where you are at, but heard this can be due to moisture getting in through the neck screws and swelling the wood of the heal forcing the ski bump. Have always put in a few drops of varnish in each neck screw hole to delay the process in my humid enviroment. Agree a defret and planing the only real way to cure once the swelling is done.
David

No, that's not the cause.
 
No, that's not the cause.

I've heard several rationales as to why the "lift" occurs, including:

*Aforementioned mounting screw / humidity theory (-).

*Compression of the heel by truss rod hardware.

*End-grain exposure coupled with the size of the heel itself in bolt-on configurations. Plausible but doesn't fully explain why lift occurs in neck-thru configurations.

*Varying rates of contraction over prolonged periods amongst different wood species & cuts (i.e quartersawn, flatsawn) used in neck construction. A good example would be a slab of rosewood glued to a flatsawn maple neck. For that fact, even a multi-lam build of the same wood may demonstrate severe ridging over time for the same reason. Phil Kubicki has acknowledged this for some time and has a "cottage industry" re-treating his 37 piece Ex Factor necks.

Riis