Re-stringing a mini classical guitar in 5ths

[ohnoitsalobo]

(Note: jump to bottom to see my actual question)

I found a cute little travel-size classical guitar (scale length 17 inches) at a local music shop where I live in Goa, India. Sounded quite nicely balanced, and it has a built-in bridge piezoelectric pickup. Cost around 6300 INR (US$93.55). As with most good instruments in India, it's imported.

Now, I can't actually play guitar. But I picked up this guitar and messed around a bit, and I realize that the fret spacing is just barely small enough for me to use mandolin finger positions with a little stretching. In other words, no need to learn a new fingering style if I can re-tune to 5ths! So I bought it immediately, of course.

(Before anyone tries to tell me to "just learn guitar, dude", here's a personal note: No, thank you. Moving on.)

Now, what I'd like to do is essentially turn it into a 6-string mandocello. It came with nylon strings, and I've rearranged them to mandolin GDAE tuning one octave below, and futzing around on that is a LOT of fun. So I thought to myself, let me make myself a unique-ish instrument that I can actually learn to play in a reasonable amount of time.

Original configuration:
- classical guitar 17" scale length
- nylon strings
- tuning: E2 A2 D3 G3 B3 E4

Desired configuration:
- 6-string 'mandocello' 17" scale length
- steel strings, low tension
- tuning: C2 G2 D3 A3 E4 B4

I'm fairly certain this is reasonable, but I'm not a luthier myself, and there are none in a very large radius. So what I need is help determining the most appropriate string gauges to use under low tension to get that tuning. I can't get custom strings locally, so using 'standard' gauges would be best if at all possible.

EDIT: I don't mind if it's not exactly CGDAEB - I would prefer if it was, but it can be lower or higher, whatever you think would work best with this scale length and low tension, as long as it stays in fifths.

[Simon DS]

The neck on this import may be really weak or strong, and be designed to be used with extremely light weight or heavy strings.
If you have the name of the import you may find the recommended weight/tensions of the original six strings and have something to go by. Then check out, for example:
http://www.daddario.com/upload/tension_chart_13934.pdf
(At the bottom of the page: mandolas are around 16/17 inches)

[JH Murray]

The tuning you are describing is known as New Standard Tuning. There are string sets sold for NST so you can compare to those.

[Brian Evans]

Part of the issue is this is a nylon string classical guitar type instrument, so steel strings won't work at all. Also, the extreme range of tuning six strings in fifths is a problem (there is a reason instruments tuned in fifths usually have only four strings) You could look at it as a classical guitar with a capo - 17" scale is about like a regular classical guitar capo'd at the 7th fret. So the first two strings (E and B) from regular classical string set will do for the high B, and the high E. I might then try the fourth string of the set on the A3, the fifth string of the set for the D3. I would then get a hard tension sixth string for the low G2. I think it's unlikely that you will get a string to sound good on the low C, that is three notes lower than a normal classical guitar with a 25.6" scale length. I would try it as a five string mini-whatever...

[EdHanrahan]

While many have experimented w/ steel-vs-nylon (mine was the other way around: nylon on a steel-string instrument), I suspect that most such experiments haven't worked: either the nylon was too light to drive the steel-intended top, or the nylon-intended instrument was too weak for the steel strings. "Low-tension" steel, at least, is a prudent approach.

Maybe a more basic question is: What's the ratio of "standard" nylon-tension to equivalent steel-string tension. I'd guess that nylon pulls maybe 25% as much as steel, or even less, but that's a guess.

FWLIW, tiple strings are steel AND relatively low tension AND on a 17" scale, at least for Martin's 10-string. Mine has the high course tuned to B (guitar 7th fret), although some folks may use A, standard ukulele tuning.

(Martin's version of the tiple is sort of a cross between ukulele and 12-string guitar, with steel strings in courses of 2-3-3-2, the lower 3 sets w/ octaves and the lowEST tuned an octave higher, as per ukulele's "re-entrant" tuning... IF anyone can keep track of octaves by then!)

Personally, for 5ths tuning, I'd be more tempted to buy several sets of nylon strings (normally defined as low-medium-high "tensions" rather than actual diameters) and experiment from there. It's just safer.

[Simon DS]

-or you could stick beautiful inlay onto it, with a gibsan label, say you don't know where it came from and sell it on ebay for $2500.

[ohnoitsalobo]

Thank you all kindly for your replies! This is a learning experience.

The neck on this import may be really weak or strong, and be designed to be used with extremely light weight or heavy strings.

Well the neck is not at all thick, so I'm going to assume it's built for low tension. See my reply to Brian Evans below about the steel strings.

... or you could stick beautiful inlay onto it, with a gibsan label, say you don't know where it came from and sell it on ebay for $2500

I could really get away with this
South/Southeast Asia is notorious for knockoff instruments (some of which can sound pretty good if you're lucky or are able/willing to work on them a bit)

The tuning you are describing is known as New Standard Tuning. There are string sets sold for NST so you can compare to those.

Thank you! I had no idea this was a thing. Spent half an hour Google-ing it and I think I should be able to manage with a bit more futzing around. Since my guitar is so small, I could theoretically achieve the high B where others have failed, but at worst I'll either tune it to G as is shown, or keep the instrument as a 5-string 'cello. Thanks again for this.

Part of the issue is this is a nylon string classical guitar type instrument, so steel strings won't work at all.

You may be right. I use standard guitar strings on my mandolin, so I used some of the spares to test out on the guitar. At low tension, the strings buzz quite a bit, but if I increase the tension to stop the buzzing, the action is too high and the notes detune horribly as I fret them. At best I'd need to adjust the nut and the saddle, with no guarantee if it would work. I don't think it's worth it, so I'll mess around with nylon strings only for the foreseeable future.

Personally, for 5ths tuning, I'd be more tempted to buy several sets of nylon strings ... and experiment from there. It's just safer.

After a little messing around with steel strings, I agree - see my reply to Brian Evans above. My gut (string? ) feeling is that ukulele strings and classical guitar strings are close to interchangeable, so I'll experiment with those next and see what is to be seen.
I hadn't heard of a tiple before, thank you for that. I'll see if that provides any insight for my endeavor. Thanks!

[ProfChris]

Tenor ukulele scales are usually 17 inches, and I think guitaleles are 17 inches too (but you should check that).

And yes, uke and guitar strings are interchangeable. But there are (roughly) three different kinds - nylon, fluorocarbon and synthetic gut (from Aquila). Each type has quite different thicknesses for the same note and different feels, so you might not want to mix then up. I'd start with nylon, as its cheapest and pretty much every string you want is available. Except perhaps C2 - I suspect your current E2 string struggles to work properly, and a C2 string would be scarily thick!

[ohnoitsalobo]

An acceptable level of success has been achieved!

All I have is my crappy laptop mic, but you get the idea from the recording. a.mp3

The tuning is C2 G2 D3 A3 E4. Forget having all 6 strings, it'll take me quite a bit of effort to get used to just the one new string. I managed to find a slightly heavier nylon 6th string, and that seems to work for the C2. It's not extremely strong, but I can hear it pretty alright when I'm practicing at home, and thanks to the built in pickup, when I take it outdoors I'll always be using it with a sound system, so that shouldn't be much of a problem.

Thanks guys!

I'll keep experimenting though, let's see what else sounds good

[ohnoitsalobo]

Well, my 'mandocello' sounds pretty alright to me. Not great, but I don't really care about greatness in this case, it's a fun experiment.

Next question, to ye mandolin-makers:
I want to double-string it like a proper mando-family instrument. I can go to the local music shop and get a new nut made and the bridge and tuners modified for 8 strings, but these guys are not actual instrument makers, although they generally do a good job servicing instruments, and have been known to modify instruments upon request.

Now, I know this can be difficult with nylon strings since they vibrate much wider than steel. But let's give it a go anyway since the neck is probably wide enough to handle it. I'm sure there must be calculations to figure this stuff out just right, but I doubt the local fellows have as much experience with these things compared to actual luthiers.

Looking at the picture I posted up top:
The nut is 45mm wide, with the existing six notches just a hair under 8mm apart.
The fingerboard is 45mm at the nut (of course) and 58mm where it ends at the sound hole.
The six existing holes in the bridge are just a hair under 11mm apart.
Nut to saddle length is 17in.
The tuning will be C2 G2 D3 A3 E4, doubled. As for string gauges, just pick up a standard classical nylon set, probably medium or hard tension (for the low C to sound strong). I'm using the 1st, 2nd, 4th, 5th, and 6th strings (E4, A3, D3, G2, C2, respectively).

So.
1) Can double-nylon-stringing be done? My gut feeling is yes, although it may not be ideal on the low strings. If not, please feel free to educate me.
2) If it's possible, can I get a calculation/estimation from the experienced makers over here as to the ideal string spacing (bridge and nut), given the dimensions I've supplied? Then I can get the local shop to modify it to those measurements and give it a go.

If you've read this far, thank you, you're awesome! :-)

[ohnoitsalobo]

I want to double-string it like a proper mando-family instrument. I can go to the local music shop and get a new nut made and the bridge and tuners modified for 8 strings ... The tuning will be C2 G2 D3 A3 E4, doubled.

So I meant 10 strings. Not 8. Stupid me, late night forum posts always with one stupid mistake, lol

Reiterating for my own benefit, as well as for newcomers to the thread:
It was a mini classical guitar when I bought it (see pic in first post);
It is now a 5-string mini-mandocello with nylon strings, and sounds acceptable;
I'd like to double the strings like a proper mando-family instrument, so I require advice on string spacing for the nylon strings, since there are no luthiers to consult locally.

I realize that it may be difficult to double the C2 string due to how wide it vibrates. If there is no way to do it, I can keep it as a single C string, or take it off entirely for the sake of the other strings. So I'd like it to be a 10-string (5-course) nylon mandocello, but I would be satisfied with keeping it as a nylon octave mandolin if y'all advise against doubling the low string.

Thanks :-)

[Ronny Stecher]

A couple years back I bought a 6 string Yamaha Guitalele for ~$75. I loved it. It was tuned like a guitar capoed on the 5th fret. The strings couldn't handle the tension on the frets and the strings separated on the lower frets. I tried a few different types of nylon strings even the treated/coated strings, but they also wore down in quick time. I was so giddy I did a mini sampler video of it, but later added the issues in the comments to advise of the issue.

https://www.youtube.com/watch?v=-VMh0paFNm8

[ohnoitsalobo]

It was tuned like a guitar capoed on the 5th fret. The strings couldn't handle the tension on the frets and the strings separated on the lower frets.

That seems like a fair concern. Thanks for the warning, I'd definitely be worried if I was tuned up that high - my little experiment here was tuned to regular guitar tuning when I bought it, and in its current state the overall tension is very definitely below rated tension for both the instrument and the nylon strings. Especially considering the scale length is 17in compared to a standard guitar's 25in or so.
Using standard nylon guitar strings tuned in 5ths, it works out like:

E4 --> E 1st string, full tension
A3 --> B 2nd string, tuned down two semitones
D3 --> D 4th string, full tension
G2 --> A 5th string, tuned down two semitones
C2 --> E 6th string, tuned down four semitones

So what I want to do is double the strings while keeping the pitches the same, to make it closer to a mandocello or octave mandolin, with nylon strings. To do that, though, I need advice on the string spacing for a new nut. I'm willing to bet this can handle the tension. If not ... well, only one way to be 100% certain :D

[ProfChris]

Last year I built this ... thing, I guess.

You don't really want to know the thinking behind it, though the Martin company had a hand in its genesis.








The important point is it's a 15 inch scale instrument, double course, nylon strung. Taropatch ukulele stringing with the 4th string in octaves using a wound string for the lower note.

It works fine without buzzing or other string interference.

Spacing between courses is 2.5mm for the thinnest strings, 3mm for the fatter ones, measured string centre to string centre. Each pair of courses is spaced at 9 mm. So the four courses occupy 30mm in total, and the nut is 36mm.

Your 45mm nut means you can add in another course using my spacing and still have 3mm either side. Or you could reduce the course spacing to 8mm, allow say 3.5mm between the thickest strings (though I suspect 3mm is enough) and have a little extra space either side.

Short version is, it will work.