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Sometimes necks when strung up will change their shape, typically most non straight grained necks will develop a twist. Any successfull repair requires us to replicate the playing position.
This guitar with no string tension applied, is perfectly straight, under tension it twists, so much so that we cannot simply fret dress it out, we need to repair and straighten the fretboard first.
Time to repair approx 4 hrs over 4 days (wood relax/stabilizing times)
This guitar with no string tension applied, is perfectly straight, under tension it twists, so much so that we cannot simply fret dress it out, we need to repair and straighten the fretboard first.
Time to repair approx 4 hrs over 4 days (wood relax/stabilizing times)
One way of dealing with warped necks is adding carbon fibre rods into the neck itself under the fretboard.
Attached link
Attached link
Carry out traditional defret process, as per attached link
Take the defret process all the way to the end, where you have carried out the first initial fretboard leveling.
With the original strings, we tune the guitar back to tension without frets.
Adjust the truss rod to zero relief, we want a straight flat board.
We now place the guitar onto a neck jig, mine is attached to the end of my work bench vee a hinge, it simply folds out of the way when not in use.
My jig laying down
You can also buy commercial versions of neck jigs from most luthier suppliers, this is a commercial version
This guitar suffers severly from a warped neck.
Examination of the grain from behind the neck shows it is quarter sawn, but off the quarter, if tension is applied or the neck is thinned down enough, it will want to twist under load, this neck may or may not be capable of supporting string tension without the assistance of the truss rod, if it relys on the truss rod and the grain of the neck is not straight, then it will naturally twist the fretboard and frets.
My red line is showing the grain direction.
Examination of the grain from behind the neck shows it is quarter sawn, but off the quarter, if tension is applied or the neck is thinned down enough, it will want to twist under load, this neck may or may not be capable of supporting string tension without the assistance of the truss rod, if it relys on the truss rod and the grain of the neck is not straight, then it will naturally twist the fretboard and frets.
My red line is showing the grain direction.
With the guitar strung up, we can see an S shape bend through the neck as indicated by my green line.
Loosen, but do not dispose of the strings yet.
We sit and strap the guitar to the jig, wind the dial indicators up until they touch the underside of the neck, adjust the bezels to make the gauges read zero
All manufacturers jigs are different, so you need to check their instructions.
Once the jig is set, we remove strings and then using a small jack under the headstock, and a strap over the nut - we apply tension back into the neck until the two gauges read zero again, this reading confirms the neck is in the same position as it was with the strings on..
All manufacturers jigs are different, so you need to check their instructions.
Once the jig is set, we remove strings and then using a small jack under the headstock, and a strap over the nut - we apply tension back into the neck until the two gauges read zero again, this reading confirms the neck is in the same position as it was with the strings on..
