13" to 13 7/8"

[Graham McDonald]

As some of you know I am slowly working on a book on the history of mandolins (from a long way from most of the world's mandolins) and currently working my way through the story of mandolins in the US in the early years of last century.

Up until the introduction of the production Gibson mandolins in 1903/4, the standard scale length of a mandolin (a bowlback) was 13". Gibson effectively increased that by one fret to 13 7/8". While I am pretty certain that the bowlback manufacturers didn't increase their scale length, by the 1920s bowlback had pretty well been replace in the US by flat instruments in all their wonderful variety. What I entirely forgot about when I spent some weeks in the US a couple of years back photographing and talking to people about mandolins was checking the scale lengths of the non-Gibson flat mandolins. Apart from the carved Lyon & Healy instruments which went from 13 7/8" back to 13" after a few years in the teens and 20s I haven't seen much mention of the scale of other mandolins. It would be interesting and useful to know how and when the shift from short scale to the longer happened.

I would greatly appreciate any owners of flat mandolins, Regal, Harmony, Schutt, Larson, Weymann, Stradolin etc etc who could measure the distance from the nut to the 12th fret along with the approximate date of their instrument(s)

Thanks

graham

[Chip Booth]

I don't have any specifics but I believe that most if not all of Martin cant top mandolins were made at a 13" scale.

[Eddie Sheehy]

My Martin A style (1925) and B Style(1926) were 13" scales. My SS Stewart(193?) was a 13" scale. I haven't noted the scale-lengths of the Vega Cylinderbacks that I've had, and the only one I have now is a 15" scale 10-string. I do have pics of several different Vega Cylinderbacks that I can share. I have an Eastman copy replica of Dawg's Bacon & Day mandolin and it has a 13 7/8" scale - but I don't know if that's a failthful reproduction or a fit to what they normally produce.

Eddie.

[Martucci]

I'm sorry I can't help with flat mandolins but I do have 3 bowlbacks made by my great grandfather in Philadelphia each has a different scale length they are 13 1/8, 13 1/2, and 13 7/8". They all date between 1895 and 1905 after which he went to work for Weymann. Good luck with your research.

Fred

[Graham McDonald]

Thanks for the info on the Martins. I suspected they never changed the string length from the earlier bowlbacks. The Martuccis are certainly interesting and very rare to find a bowl back with a longer scale than 13", let alone three different scale lengths on three instruments.
So far I have established the Howe-Orme, the Stahl violin bodied mandolins and at least some of the Regal reverse scroll mandolins at 13". Any other measurements welcome.

thanks

graham

[brunello97]

Graham, the Leland flatbacks that I have (and love so well) be they Larson/Vega/L+H made are all 13" scale. I don't have a solid date on them but this line was out +/- 1910. But for my '51 Martin, my non-bowlback flat-top posse has shrunk to the Lelands. I would love to add a '20s Vega or Washburn flattop/back sometime.

Mick

[mandroid]

I have a Leo , Denver made Travel/pocket mandolin, it is 13" scale..

I used to own a CF Martin made Bowl back.

[Jim Garber]

Here are a few:
Levin 1950 Model 46 Classic: 13 7/8"
Bacon Amateur: 13 7/8"
Bacon Artist (1921): 13 7/8"
Leland Piccolo: 10 1/4"
Weymann (Strad-O-Lin clone): 13 5/8"

[Graham McDonald]

Thanks guys,

That is certainly shifting the focus a bit, and not quite what I expected (not that I am sure what I expected !). If I can get some data on a few more Stradolins and some more of the mass market Regals and Harmonys that would excellent. Weymann and Schutt would be interesting as well as unusual approaches.

cheers

graham

[Masterbilt]

I am working on a history of pre-Gibson era Epiphone instruments including mandos.
In 1931 Epiphone introduced the Masterbilt line of archtop guitars and mando family instruments.
From what I know Epiphone was experimenting with different scale lengths over the years. I own an early c.1932 Adelphi model with a 15" scale, and know of a Strand model of that period with the same scale. Some people have suggested that these are mandolas but I am not quite convinced. (Also on their archtop guitars Epiphone used longer scales than Gibson at the time.)
Several c.1933 Epiphone mandos in my database have a scale length of 14". By the late '30s Adelphi models seem to have gone to a shorter scale length of around 13". I know of several '50s Rivoli models with a 14" scale.
It would be interesting to know from other Cafe members who own Epis what's the scale of theirs.
Felix

[Graham McDonald]

The 15" scale is certainly interesting. Orville Gibson was experimenting with a 15" scale on his early mandolins, but was had too many e strings break so went back to 13 7/8", though why that particular length is a question I have been asking myself. The accepted way of calculating fret position these days is to divide the scale length by 17.817 and then add a little for compensation. The old way was dividing by 18 which shifted the fret position a touch, but built in compensation, at least on gut strung instruments. I think I need to find some really early Gibsons and do some accurate measurements on fret positions and try to work out how they worked out where they were cut. There are many stories of mandolins from the '23-24 period not playing in tune, possibly because of the realignment of the spacers in the Gibson gang saw after a periodic dismantlement for maintenance, and the fret slots being cut in the wrong places.

cheers

I am working on a history of pre-Gibson era Epiphone instruments including mandos.
In 1931 Epiphone introduced the Masterbilt line of archtop guitars and mando family instruments.
From what I know Epiphone was experimenting with different scale lengths over the years. I own an early c.1932 Adelphi model with a 15" scale, and know of a Strand model of that period with the same scale. Some people have suggested that these are mandolas but I am not quite convinced. (Also on their archtop guitars Epiphone used longer scales than Gibson at the time.)
Several c.1933 Epiphone mandos in my database have a scale length of 14". By the late '30s Adelphi models seem to have gone to a shorter scale length of around 13". I know of several '50s Rivoli models with a 14" scale.
It would be interesting to know from other Cafe members who own Epis what's the scale of theirs.
Felix

[acousticphd]

I have a Supertone (Harmony/Regal-esque) flat-top I believe to be from the early 1930s. Scale is 13".

[Jim Garber]

There are many stories of mandolins from the '23-24 period not playing in tune, possibly because of the realignment of the spacers in the Gibson gang saw after a periodic dismantlement for maintenance, and the fret slots being cut in the wrong places.

I never quite heard what the reason was but that sounds like a promising hypothesis. All I know is my luthier compared my 1924 F4 to a properly laid out fretboard and it got really dicey esp up the neck.

[brunello97]

...There are many stories of mandolins from the '23-24 period not playing in tune, possibly because of the realignment of the spacers in the Gibson gang saw after a periodic dismantlement for maintenance, and the fret slots being cut in the wrong places.

cheers

This seems like a classically apocryphal story and worthy of a clear thread and discussion of its own. Hard to fathom how the beginning Loar years could be simultaneously so meticulous and so careless. My hunch is that this has been discussed here a lot in fragmented conversations. I'd love to get some of the big Gibson wonks (Tom, Dan, Joe, Big Joe etc.) to lay this out in a clear, concise fashion.

Mick

[Graham McDonald]

This seems like a classically apocryphal story and worthy of a clear thread and discussion of its own. Hard to fathom how the beginning Loar years could be simultaneously so meticulous and so careless. My hunch is that this has been discussed here a lot in fragmented conversations. I'd love to get some of the big Gibson wonks (Tom, Dan, Joe, Big Joe etc.) to lay this out in a clear, concise fashion.

Mick

The story about the Gibson gang saw has come up several times. I was (is?) supposed to be a universal fret slotting machine with what would have to been 35 or so fine circular saw blades all accurately separated by spacers so as to be able to slot a fretboard from guitar/banjo down to mandolin sized fretboard, just depending on which saw was considered the nut. What I have never tried to work out is if a 13 7/8" mandolin fretboard could be cut on the same machine as a 15 3/4" mandola or a 24 3/4" guitar scale. I shall play around with that this evening. And getting back to my original question, what mathematical formula was used to calculate the thickness of the spacers.....

And then there is the question of what happened in 1923/24 to make the mandolins play so noticeably out of tune.

cheers

g

[Martin Jonas]

I need to take a ruler to my bowlbacks, but I know that my Vinaccia is 13" and that Ceccherinis are quite a bit longer -- 13"-1/4, I think, but I have to measure. I also have a guitar-shaped German archtop mandolin with a 14"-7/8 scale. No idea whether this was intended as a mandolin or mandola. Sobell mandolins are long-scale as well, I think.

Martin

[Jim Garber]

Strange... this Bruno bowlback at Elderly is listed has having a scale length of 13 1/4 inches.

[brunello97]

Strange... this Bruno bowlback at Elderly is listed has having a scale length of 13 1/4 inches.

You guys have got me out (re) measuring all my instruments. I wonder if the Bruno scale is measured 2X distance to 12th fret or measured from nut to bridge? I have found that the location of the cant on US bowls varies quite a bit (construction tolerances being what they were.) If the bridge was set sort-of near the cant but not accurately placed relative to the proper scale, a 1/4" measurement deviation doesn't seem completely improbable.

Some of my MOR Italian bowlbacks seem clearly to have had the frets cut once the fretboard was on the neck (with the thin fbs used, it is hard to see how they would otherwise. Still the accuracy varies widely. Not sure what practice was used in the heyday of US bowls, but the fbs were thick enough that I haven't come across a mandolin where the cut for the fret went all the way through the fb into the neck wood.

I hope to hear more about the Gibson fret cutting story. Hard to imagine a company in business for 20 years (by that time) going so off on what one would assume to be a fairly manageable bit of industrial engineering. (Across the state Henry F was hard at work standardizing auto assembly.) Still, S happens. But during the era of Loar quality control? Interesting story to unfold.

Mick

[Graham McDonald]

Measuring scale length accurately depends on how it was calculated. If you use the modern 12th root of 2 divisor of 17.817 the calculated distance to the 12 fret is almost exactly half the theoretical scale length. But we know that we have to add a few mm to the string length to make it play in tune, which may be why a 13 7/8" scale is often considered to be 14", because it is that far from the nut to the bridge. If you use the older Rule of 18 divisor (rather simpler maths) that extra compensation factor is built in and the bridge will be at the theoretical scale length, but the frets will be slightly closer together. For a 13 7/8" / 352.425mm scale, instead of the 12th fret being at 176.21mm from the nut, the 12th fret is 174.93mm from the nut and if the e string part of the bridge is placed 13 7/8" from the nut, it will probably play pretty well in tune.

I am curious as to when the change from calculating by 18 to 17.817 took place (and 17.835 is mentioned often in the 1960s as the divisor as well) but I can find little information. Attached as a jpg are the first 12 fret positions of a 13 7/8" scale calculated by the 17.817 and 18. in MM I am afraid, with entirely too many decimal points.

cheers

You guys have got me out (re) measuring all my instruments. I wonder if the Bruno scale is measured 2X distance to 12th fret or measured from nut to bridge? I have found that the location of the cant on US bowls varies quite a bit (construction tolerances being what they were.) If the bridge was set sort-of near the cant but not accurately placed relative to the proper scale, a 1/4" measurement deviation doesn't seem completely improbable.

Mick