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Hello all. It’s been a long while since I’ve been on the boards but I have a tenor uke question that I hope you can answer regarding string location relative to the edges of the fretboard. Do you space your bridge pin holes so that the outer strings run parallel to the fret board edge for the full length of the fretboard or do you slightly increase that gap as you move down the fretboard towards the bridge?

My tenor uke is a 12 fretter and the nut is 1 3/8” wide and I’ve positioned the outer strings 1/8” in from the outside edge of the nut. The width of the fretboard at the 12th fret is 1 ¾”. The plans I am using call for a 1 ¾ “ total distance between the string no. 1 and no. 4 holes in the bridge which I think is fairly typical. However, that results in a noticeable widening of the gap between outer stings and the outer edge of the fretboard as the stings move towards the bridge. Increasing the sting spacing at the bridge so that the outer strings run parallel with the outer fretboard edge results in a total string spacing at the bridge string holes of 1 ¾” which seems a bit excessive.

Any thoughts?

Thank you!

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Doug Mills
Chicago, Illinois

I widen the gap. That looks fine to my eyes.

My number 1 priority is playability, and so the spacing at the bridge needs to suit the player.

A secondary advantage is that I can adjust the bridge location slightly for aesthetic reasons, and still keep the strings over the fretboard

I use a slightly wider gap (5/32) at the 12th fret than at the nut.
I adjust the fingerboard taper accordingly.
Here are my numbers: (sorry the column/ tabs just don't display properly)

In 64th mm
Scale Length 17.000 17 431.8
12 or 14 fret 12
Number of frets 18
Compensation % 0.620 7/64 2.7
String-Fingerboard edge at Nut 0.125 1/8 3.2
String-Fingerboard edge at Body 0.156 5/32 4.0
String Spacing at Nut 1.125 1 1/8 28.6
String Spacing at Bridge 1.750 1 3/4 44.5
Compensation 0.1054 7/64 2.7
12 Fret distance 8.500 8 1/2 215.9
Fingerboard length (1/32 added) 11.021 11 1/64 279.9
Nut - Comp. Saddle Dist 17.105 17 7/64 434.5

FingerBoard Width at Nut 1.375 1 3/8 34.9
FingerBoard Width @ Body 1.734 1 47/64 44.0
FingerBoard Width @ Hole 1.840 1 27/32 46.7

When I am laying out an instrument (usually a guitar but just did this for a tenor uke I am making), I determine the nut width I want and the string spacing at the saddle. I use the number for my saddle spacing as the width of the fretboard at the 12th fret. That defines the taper. It sounds like your plan is no different here.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Thank you for the advice guys. I think I have it dialed in now - a slight widening of the gap as the stings move towards the bridge.

_________________
Doug Mills
Chicago, Illinois