Measuring frets for multi-scale bass

[Bryan Harris]

I can't recall ever seeing this particular question addressed here, and that may be because I'm making a big deal out of nothing, but, that's what we do, right? So, here goes.

I'm in the final stages of a multi-scale (34"-35") 5-string bass. I'm getting ready to measure off the fret slots, and it occurs to me that I'm not sure exactly WHERE on the string path to do the measuring. Because the nut is angled, the string contacts the nut at different distances from the saddle on opposite sides of the string. Obviously, this difference is small, but is it big enough to matter? My thought is to take the measurement from the point at which the distance betwixt nut and saddle is the shortest (the treble side of the string), because that's where the vibration stops, but I thought I'd consult the wisdom of the MIMF before I actually began cutting. In your collective opinion, do I:

a) measure from the treble side of the string,
b) meausure from the center of the string,
c) quit worrying about it, because the difference is so small as to be negligible, and instead spend my time worrying about my fretboard inlay design (which is a question for a different topic entirely)?

Many thanks in advance for your input. This beast is 3+ years in the making, and I'm eager to get her going.

[Chris Reed]

I'd say (b), with a fairly large helping of (c).

The centre of the string is clearly the right answer (that's the average length of the string, shorter one side, longer the other).

Also you can work out your potential error. Assume your thickest string is at the 35" side, and 1/4" wide. Assume spacing between outer strings of 2". At most you're 1/8" out, which is 1/16 of the extra scale length, i.e. 1/16". Thus you are out by 1/(35*16), or less than 1/500 (0.2%). Doubt you'd hear that.

[David King]

If it was a guitar someone might hear it but on a bass never. I'm curious why you're choosing 35 and 34" scales, those two are so close I wouldn't think the the tiny change in string tension would be worth all the extra effort.

[Jason Rodgers]

Draw it out full-scale:
- Fretboard with taper.
- Use WFret or similar app to print out a template of your chosen scales.
- Lay out and mark the treble-side scale along the tapered edge.
- Decide on your perpendicular fret and line up the bass-side scale at that point.
- Lay out and mark the bass-side scale along the tapered edge.
- Connect the treble and bass scale marks (bridge, too).

Or just go play around with FretFind2D.

And consider what David is saying.

[Bryan Harris]

Yeah, I figured I might be overthinking things. And, I suppose, as long as I do the same thing on each string, it'll all work out when I intonate the bridges anyway, right? Thanks for the advice, folks.

Oh, and David, that should have read 34"-35.5", so the difference is 1.5". Not a huge distance compared to some other multiscale instruments out there, but 35.5" is about the most my left hand can comfortably handle, and when I made my original mock-up fretboards (auto pinstriping tape for frets), the 1.5" differential ended up being the most comfortable, at least for now. So, I'm gonna go for it. I can always build more, yes?

Thanks again.

[David King]

As Jason has mentioned the http://www.ekips.org/tools/guitar/fretfind2d/ is an amazing layout tool in terms of refining your scales and deciding where you want the perpendicular fret to be.