Simple Question - Measuring Scale Length

[drozzy]

Okay, heres the point wher ei think i am way over my head, but i'll persevere and hopefully make a decent bass!

Heres the question, I am making a 34" bass guitar, but and unsure of how to measure this length. Is it to the start of the nut? Which part of the bridge to i start from?

All help is greatly appreciated.

[pilotjones]

It sounds like you haven't gotten a book. You should seriously consider doing so. I was able to borrow the Hiscock book from my local library. Your question is a point of basic understanding in instrument design, so it's quite likely that there are several other things you don't know, that may spoil your build.

34" is the distance from the point the string leaves the nut (the edge facing towards the bridge), to the position where the string hits the bridge saddles, before the saddles are adjusted backward for intonation.

[drozzy]

I have a book, but this is the one point it didnt touch on, and I knewit was from the bridge to the nut, just not the finer specifics of it.

Thanks for the reply, it will prove very helpful

[BassShifter21]

Originally Posted by pilotjones

It sounds like you haven't gotten a book. You should seriously consider doing so. I was able to borrow the Hiscock book from my local library. Your question is a point of basic understanding in instrument design, so it's quite likely that there are several other things you don't know, that may spoil your build.

34" is the distance from the point the string leaves the nut (the edge facing towards the bridge), to the position where the string hits the bridge saddles, before the saddles are adjusted backward for intonation.

Thank you!!! Here, finally, is the answer I have been looking/searching/hoping for. EXCELLENT

[daveman50]

"...to the position where the string hits the bridge saddles, before the saddles are adjusted backward for intonation."

I disagree. I have always understood that scale length is measured by doubling (2x) the distance from (i) the forward edge of the nut to (ii) the crown of the 12th fret.

If you try to measure with reference to the bridge, you will not get accurate results. There is no benchmark as to where the saddles are "supposed " to be -- the bridge can be installed (front to back) within a range of locations.

[ROCKWOOD]

When laying out a new bass, I'll mount the bridge where the saddles
are adjusted to midpoint for the scale I want. This way there is plenty
of adjustment in both directions.

[daveman50]

Originally Posted by ROCKWOOD

When laying out a new bass, I'll mount the bridge where the saddles
are adjusted to midpoint for the scale I want. This way there is plenty
of adjustment in both directions.

Agreed.

[Rodent]

Originally Posted by ROCKWOOD

When laying out a new bass, I'll mount the bridge where the saddles
are adjusted to midpoint for the scale I want. This way there is plenty
of adjustment in both directions.

and in doing so you will lose nearly 50% of your adjustment range since you almost never need to adjust for a length shorter than the scale length (in this case 34")

we did a long thread on the topic of bridge placement some time ago, and no builder could reference a time when they needed to set the intonation significantly shorter than the scale length. giving yourself about a 1/16" adjustment shorter than scale length will easily accommodate for that one time you encounter the freakish anomaly of a string intonating shorter than scale length


the most accurate way to measure scale length is to double the distance from the fretboard edge of the nut to the crown on the 12th fret ... but measuring from the nut to the g-string bridge saddle will net you close enough to grasp that you're working with a 34" scale and not a 34-3/16" scale

all the best,

R

[ROCKWOOD]

Then again Rodent; I've never had to go a 1/4" in the other direction either. Yours is
the first better than a simple safe common sense approach view I've seen. I thank
you for your input!!!

[pilotjones]

Originally Posted by daveman50

"...to the position where the string hits the bridge saddles, before the saddles are adjusted backward for intonation."

I disagree. I have always understood that scale length is measured by doubling (2x) the distance from (i) the forward edge of the nut to (ii) the crown of the 12th fret.

If you try to measure with reference to the bridge, you will not get accurate results. There is no benchmark as to where the saddles are "supposed " to be -- the bridge can be installed (front to back) within a range of locations.

I think you're getting a little too far into words/semantics/etc. here. Double the 12th fret distance is identically the scale distance. This is denoted at the bridge end by the virtual bridge line, which is the virtual point of the end of the vibrating string length if the string did not need intonation setback for various real-world reasons.

Like Rodent said, a a few years ago I started a thread to specifically ask whether anyone had ever needed to move the saddle from the virtual scale position towards the nut to intonate. It was 99.9% no, with one person saying they (I think on only one occasion) had to move the saddle a smidge upwards. And if you allow for the possibility that that person may be mistaken, having possibly mounted the bridge plate lower than intended, then that might even remove that exception.

True, there is not requirement for the bridge plate position. But as R suggested, if you mount it too high towards the neck, you may loose in three areas. First, you are more likely to run out of intonation travel. Second, you can more likely end up with the grubby-string-winding-start-and-silk landing on the saddle. Third, with some bridges you will get an overly sharp break angle at the saddle.

[Rodent]

and here would be that thread: Intonation compensation--Ever gone backwards?

if you read it, you'll note that there's just one person noting they needed to intonate a string less that scale length ... and go figure, it was on a geetar



hmmm ... maybe Mike Watt used a string shim on his E-string because somebody mounted his bridge too close, and he suffered from all three consequences noted above



all the best,

R

[Jazzdogg]

I have never needed to extend a bridge saddle toward the nut, but I did run out of travel in the opposite direction on a factory-made 5-string bass (I had to reposition the bridge), which would seem even more likely if one were to position a bridge with the saddles at mid-span.