Mandolin scale length: Is 15" pushing it?

[Jason Rodgers]

I am pert near completely ignorant about mandolins - maybe held and played one once - but I'm drawing up some ideas for a quick mando project to attempt this summer. With the F-ish body shape I've created, this instrument will need a longer mandolin scale: I've started with 14", but 14-1/2" looks good, and 15" might even be better.

I know, I know, this is totally a tail-wagging-dog approach, but I'm not going for something traditional. Besides, I'm a little worried about being able to play something as small as a typical 13-7/8" scale.

Over on Mandolin Cafe, I found a discussion about mandolins with 14"+ scales, and some folks think they're great with lighter strings, and others think it's pushing the limits of playability and the appropriate voice for the instrument.

Anybody tried a long mandolin?

[Mark Swanson]

I think that would be too long, Jason. I have only built standard scale mandolins and the strings seem plenty tight enough at that scale. I can't imagine jacking it up over 1 inch further....
When drawing up new shapes, I find it best to start with a blank page with just the fret scale and bridge on it, and then draw the body shape around that.

[Jason Rodgers]

Yeah, that's how I usually do it, too, Mark. I sketched a design on a sheet of 8x11 paper, then had it blown up at Kinko's. One dimension is pretty critical to the design, but it makes the another the problem here. When I lay it over a centerline with various scale lengths, 15" puts the bridge and body join in the best location. I might have to continue playing around with scaling.

[Randy Roberts]

If kinko's could blow it up, couldn't Kinko's shrink it down to 14" scale dimensions?

[Jason Rodgers]

Yes, but I'm just going to keep on tweaking what I have. It's close, so I'll keep sketching. Besides, it was like $5 for one print!

Doing a bit more searching on the longer scale, I've found that National reso mandos made in the 20s had 15" scales. Also, a couple chaps in the UK, one being Roger Bucknall, make mandos with a 375mm (or 14-3/4") scale. Folks on the Mandolin Cafe suggest D'Addario J-73s (lights) to keep the tension in check. I might not be that far off from something that will work ok.

And c'mon Randy: no quips on me starting yet another project?!

[Randy Roberts]

No Jason, I envy you having so many projects to finish in retirement, you definitely won't be bored.<g>

[Chris Reed]

I've gone the other way, making a couple of shorter than normal scale ukes (11 inch as opposed to my usual 13.5 inch). In theory I could use heavier strings (in your case lighter) to tune them to the normal pitch, but this tends to produce poor sound and intonation problems.

So the answer is to tune higher (in my case) or lower (in yours). So far as I'm aware there's no law demanding we tune to a particular pitch. In your case my guess is that tuning a whole tone lower, using standard strings, would work fine. Transposing by a whole tone is tricky for about a week, and then becomes really easy. And there is the additional benefit of flustering anyon who borrows your instrument!

This is what I did BTW, sizing the uke to match the wood I had available.


IMAG0420 by profchrisreed, on Flickr

IMAG0422 by profchrisreed, on Flickr

IMAG0424 by profchrisreed, on Flickr

[Jason Rodgers]

I like what you did there, particularly on the back. Alas, I'm bound and determined to stretch this thing out and tune it standard. Another "solution" I saw out there on the interwebs is to add a 5th 'C' course and call it a long scale 5-string mandolin, or a short scale 5-string mandola. Or maybe tune it all funny and call it a stumpy cittern!

[Bryan Bear]

If 14.5 is good and 15 is better, is 15.5 best? If so, you could do 15.5" tune down 1 full step then keep a capo handy. 15.5 inches capoed at the second fret is 13.809, pretty close to 13 7/8. String tension would be just about right and you could learn mando with the capo. Eventually you may decide to play without the capo fretting the "open" strings and you'll be glad to have some extra low notes.

[Jason Rodgers]

That's an interesting idea, Bryan. 16" is a mandola (tuned like a viola C G D A), and a little retune and a capo on the 2nd would put it in the mandolin neighborhood. I shall consider.

[Andrew Jerman]

I absolutely love my 14.5" scale mandolins, especially my five string. I can tune them either CGDA or GDAE. I think 15" is too long for a mandolin player to transition from a standard scale.

[Jon Whitney]

I haven't played mandolin for more than a few minutes but I did learn that mandolin chords are already a stretch at least for my hands. You have to cover 5-7 frets instead of the usual three or four for a guitar or banjo. A longer scale might make this impossible to chord - though I suspect you'd be OK on melody still.

[Jason Rodgers]

While these instruments might not look it (yes, plural - I plan a flat top and an arched top), my idea is to learn some Irish tunes. So, melody is my first intention, but being able to tune to mandola (or cittern/bouzuki tuning) is a secondary possibility.

I am about to sit down to the full-scale sketch again, and I will give 14.5" and 14.75" a try and see how it looks.

Of course, I realize that folks will now want to see the resultsr of all this speculating. I have a pile of other projects (as always), but this is meant to be a modular design that can be hammered out quickly. We'll see...

[Bryan Bear]

. . .this is meant to be a modular design that can be hammered out quickly. . .

Famous last words. We'll keep updating this thread with requests for progress updates <G>

[Chris Reed]

I haven't played mandolin for more than a few minutes but I did learn that mandolin chords are already a stretch at least for my hands. You have to cover 5-7 frets instead of the usual three or four for a guitar or banjo. A longer scale might make this impossible to chord - though I suspect you'd be OK on melody still.

Tenor banjos and guitars are often tuned in fifths, just like a mandolin, with something like a 23 inch scale, and play chords a lot. The proposed scale would certainly be playable with practice.

[Jason Rodgers]

Yeeeaaaaaah, that's what I was worried about, Bryan.

Right, Chris, and 23" is also an octave mandolin, which I considered, too. I'm not overly concerned about too much space for my needs. Folks have played with all sorts of scales and have made it work.

Well, after another session with the paper and pencil, I'm gonna go with a 14.75" scale for this iteration. I have been staging some woods and I'll start making sawdust tomorrow. Dang, I should get my act together at more opportune times: every piece of wood will be reused from scrap. This smells like a Challenge!

[Bryan Bear]

How about a progress report?

Too soon? <G>

[Jason Rodgers]

Ha! Actually, as I'm a teacher on summer break, I'm getting a ridiculous amount of work done. Well, at least to me it's a lot of work. To everyone else it's probably just another weekend in the shop.

Anyhoo, yes, I can report progress. Since these mandos will have solid frame-style bodies, yesterday I jointed and glued up some old Doug fir stair treads (from a remodel on our house), and today I cut them out and sanded them to nearly final shape on the OSS. In the meantime, I've steam bent a top for the first instrument using the technique presented here http://www.mimf.com/phpbb/viewtopic.php?f=5&t=2165. I even contacted this builder and asked a few follow-up questions. The back that goes with it will be bent later when the top has dried and comes out of the clamping form. The top and back of the second instrument have been jointed and glued and will be thicknessed and braced in time. I should probably dig through my stash and figure out some stock for necks next. All of this is being documented, by the way, and I'll put up a full run-down when they're complete.

Progress, woo-hoo!

[Clay Schaeffer]

Hi Jason,
One thing to keep in mind is that the "breaking pitch" of a given material (plain steel?) remains the same regardless of the gauge of the string. As you increase the length of the string you get closer to the limit for a given pitch. Have you tested whether a 15 inch S.L. will come up to the standard high e string without breaking ?
Getting too close to breaking pitch (more than 90% ) makes for a lot of string changes. <g>

[Jason Rodgers]

No, I haven't tested this myself, Clay. I'm totally going off of other people's experiences. I am backing off to 14.75", and that seems to have worked for some folks. It might be pushing it, still, but if these instruments crash and burn, I'll only be out my time plus tuners, frets, and strings. If anything, the necks will be bolt-on and I could always make new necks for shorter scales. This is all about experimenting!