Archtop Guitar to OM conversion scale?

[Dave Hulse]

I took an old Kay archtop with a 25.5" scale length and converted it to an 8 string octive mandolin. While I really like the sound,there was just too much real estate on the neck to be very playable. After hearing about repairing necks that had been broken, I figured a good luthier could shorten and narrow the neck and make this thing sound nice and be more playable.

I have contracted with a local luthier to do the work and I need to decide on the scale length. Looking at the Sound To Earth web site it seems most of the Weber scales are in the 23 inch range. I see a lot of discussion of 20 to 22 inch scales being nice also with tradeoffs in tone and sustain. Is there much difference between say 23 and 22 inches in an OM fretboard?

I am also having a non-adjustable truss rod installed. Any thoughts over steel tube or carbon fiber. I like the strength of square tube.

Thanks for the input.

Dave

[Audio Artillery]

I figured a good luthier could shorten and narrow the neck and make this thing sound nice and be more playable.

Hmmm... like remove the headstock, shorten the neck, and re-attach the headstock? Sounds messy.

Have you considered installing a zero-fret-style nut behind the 2nd fret? I mean, that's kind of a hack job approach but it's simple enough to do. I guess you'd need to do something about the (lack of) break angle.

The simplest solution of course is to just tune down a full step and capo at the 2nd fret.

[mandobassman]

I would think that tuning down a full step and putting a capo on the 2nd fret would give you very loose and sloppy feeling strings. Plus, that doesn't help the neck width problem.

[Paul Hostetter]

I took an old Kay archtop with a 25.5" scale length and converted it to an 8 string octave mandolin. While I really like the sound, there was just too much real estate on the neck to be very playable.

I assume what you mean is that the frets are too far apart for comfortable fingering. Width is another issue, but fret spacing is more important. Any neck can be narrowed in place.

If you don't own a capo, surely you can borrow one. Most of your questions can be answered by your own direct experience. Capoing at the 2nd fret gives you a scale of just under 23". Put one on there, tune the instrument back down to your preferred pitches, and see what it sounds and feels like.

After hearing about repairing necks that had been broken, I figured a good luthier could shorten and narrow the neck and make this thing sound nice and be more playable.

More playable, certainly, just like putting on a capo. Sounding nice? You be the judge. Whether you call it tone or sustain, or just fret buzz, this is the trade-off.

Is there much difference between say 23 and 22 inches in an OM fretboard?

About an inch. Capo to the third fret and find out what it sounds and plays like. In practical terms you'll probably want to change the string gauges and the setup on a shorter scale, but no amount of internet advice is going to come close to a few minutes of direct experience.

I am also having a non-adjustable truss rod installed. Any thoughts over steel tube or carbon fiber. I like the strength of square tube.

I cannot fathom why anyone with a choice during construction would deliberately not put in an adjustable rod. It's no harder to do than a non-adjustable, and it's so much more useful later on, especially if you're planning on having a narrower neck. How can you predict what that neck will do over time?

[Dave Hulse]

I cannot fathom why anyone with a choice during construction would deliberately not put in an adjustable rod. It's no harder to do than a non-adjustable, and it's so much more useful later on, especially if you're planning on having a narrower neck. How can you predict what that neck will do over time?

I was thinking that there would be more work putting an adjustment in the headstock so the cost would be that much higher.

[Paul Hostetter]

It should be hardly any more work, but consider carefully how much more you want to invest in what was a very modest instrument in the first place.