Fretting A Neck With Backbow.

[CGHbuilder86]

Yesterday I was stringing up a flattop guitar that I built from scratch. It really burned me up when I realized that the truss rod I installed was NOT a double action truss rod. It would correct upbow but not back bow. Well, my guitar has a very slight backbow when there are no strings on it. When you put the strings on it, it pulls the neck into a perfectly straight position with just a little relief. Of course when you take the strings off there is that very slight backbow. Now my question is wouldn’t that turn the simple fret leveling job into a bear of a fret leveling job. After I leveled, crowned and dressed the frets, fretting a string at the first fret would cause it to buzz, every where else it was fretted it sounded fine. I kept on filing all of the frets down except for the first one, (I did not touch the first fret) until there was no more buzz. The guitar sounds and plays great now, except that the frets along the middle of the necks length are a little lower than they should be, but they’re plenty high near the nut. I’m thinking that the reason it was buzzing when fretted at the first fret, and the reason that the frets are to low in the middle of the neck is all due to there being a natural backbow in the neck. Any info, thoughts, or opinions would be greatly appreciated. Thanks!

[Southpa]

Aside from pulling off the fretboard and installing a dual action trussrod, I guess you have no other options. You loosened the trussrod until slack and still had backbow? I'm wondering how you managed to level the frets when you first built the guitar.

Edited November 3, 2004 by Southpa

[CGHbuilder86]

I just finished the guitar yesterday. That was the first time I had put strings on it.

If I was going to take off the fingerboard and replace the truss rod, how would I go about refinishing the edge of the fingerboard, wouldn’t it be hard to make it look smooth?

[darren wilson]

Why not remove the frets and plane the fretboard so it's flat, then re-fret it?

[frank falbo]

First, if you just built it, I would expect the neck to pull into more of a forward bow as the instrument settles in. The way it plays now is not the way it will play in a month. Second, you can correct that backbow without removing the board. If you refret the instrument, you can open up the fret slots with a dremel bit or a wider saw blade, and use the glue in fretting method. You can also deepen the slots. Those kerfs will weaken the neck and allow it to pull into a forward bow under light string tension. A backbow with no tension is not uncommon, and it's perhaps a natural occurence with the fret slots being crammed with tang. Less pressure in each slot will relieve that. And varying the tension from one fret slot to another is a variable way to hone in on problem areas in a neck, such as truss rod dead zones, or hot zones, or wood inconsistencies.

[Setch]

You've missed your window of oportunity this time, but for the next time:

1. Tune it up a fullstep and leave it to settle in before levelling.

If that doesn't work...

2. Heat the fretboard with a heat blanket or regular clothes iron. Once you've got it nice and hot (not hot enough to blister the finish!) clamp the neck to a dead straight beam (I use mild steel square section) with a shim in the centre of the neck to introduce some relief. Leave it overnight to cool and it should be dead-straight or fractionally forward bowed once you unclamp it.