Issues with Fretless Nut Action

[Dubraw-Luthier]

I started setting up a Mexican made fretless j-bass, and when i got around to setting the nut hight i realized that the nut was already so low it was almost none existent, yet i was still getting a reading from the feeler gauge that it was high. The nut was the only part of the set up that had issues, truss rod, string hight, and intonation we a breeze. I was wondering if anyone else had run into a similar problem, or if anyone has suggestions.

[joinercape]

I've run into this a few times over the years, you end up with very little material above the fingerboard. My solution was taken from observing the nut om my double bass....more material below the level of the fingerboard. The first one I did was on a Fender. I simply routed the nut slot deeper and removed the typical Fender curve, making the nut slot flat bottomed. This allowed for more material to be left over after grinding down what was above the board to little more than half the height of the string thickness. I also found it advantageous (sp?) to remove a bit of material from the end of the fingerboard behind the nut so as to allow more string angle. It worked fine, though you should take note oof the string angle before you do that and be sure whatever string tree there is will allow the string to follow the steeper angle. Hope this helps. Most nut problems IME are too little (most common) or too much (rare, but just as bad) string angle, and too tight or too loose slots. Best of luck.....

[walterw]

Originally Posted by joinercape

...after grinding down what was above the board to little more than half the height of the string thickness...

that's awfully high, especially since there's no metal frets to rattle against.

there's no reason for the string slot to be any more than .010-.012" higher than the fretboard, assuming the board itself is straight. any higher just makes the thing hard to play and throws off the intonation of the first few "frets".

or did you mean that the top of the nut ended about halfway up the strings? 'cause that's normal, if irrelevant to playability.

[joinercape]

Yes, the top of the nut needs to be no more than half the strings thickness IMO. Your take on the clearance to the board is fine, could be even closer if the board is good and the player doesn't mind a bit of relief as opposed to a very flat board. I'm used to relief personally from DB, and tend to play harder than I probably should on electric! Good info....JJ