Uptuning (I need some advice)
 

I just bought a Kremona 3/4 size classical because I'm 91 & can't handle a full-size or steel strings any more. It's now tuned E to E but I want to uptune it 3 semitones to G to G. It has no truss rod so the neck *might* get screwed-up, but that's a risk I'm quite willing to take.

QUESTIONS:
1- To reduce the possibility of harming the neck, should I use low tension strings or...?
2- On the other hand (and never mind the risk of harming the neck), would medium tension strings be more likely to give me better resonance at G to G tuning?
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P.S. It's a bit frustrating that guitar makers assume that a 3/4 size guitar is only for kids. As a result, I searched long & hard trying to find a 3/4 size, all-solid-wood, nylon stringed guitar. No success, so I bought the Kremona (solid top, B&S plywood) & it turned out to be pretty good for a low-priced instrument. Made in Bulgaria, I think.

Body size or scale length?
 

I’d be surprised if tuning normal tension classical strings up a tone and a half would cause serious damage to the instrument’s neck, but to be on the safe side you could do this incrementally: bring up to F, wait a few days, then measure relief and action.

Depending on how stiff the neck and top are, you may well find the playing action rises as string tension pulls the neck forward and rotates the bridge. That’s a good argument for increasing tension in semi-tone increments.

Low tension classical strings are usually only slightly lower in tension than typical normals, roughly 80 vs 85 lbs total tension, but certainly worth trying if increasing the pitch on your normal strings introduces too much relief.

I’d be interested to know the scale length of your guitar; measure the distance between the front of the nut and the centre of the 12th fret, then double that.

Was your reason for going with a 3/4 guitar to have a shorter scale length and/or smaller body? There are high quality classical instruments available which might fit the bill; some Torres size instruments are considerably smaller than their modern counterparts and have a reduced scale length.

Hope that’s of some use.

Many many thanks for your VERY helpful comments!!! :)

Scale = 580mm/22.83"

Both. I am 91 so I want an easier playing guitar: (a) nylon VS steel strings, (b) smaller body for my slightly arthritic arms, & (c) shorter scale for my slightly arthritic hands.

Aloha from Hawaii :guitar:

A Wee Lowden is definitely not a kids guitar - probably the highest-end small guitar there is.

You should also check out a Taylor GS Mini - definitely not a kid guitar and super high quality - especially the "mahogany" version.

And Ed Sheeran had played a Little Martin for a very long time (until he got a signature Wee model from Lowden then his own line)

This information might be useful:

Terz Pitch and Scale
The Terz guitar is tuned a minor third higher than a regular guitar, the same tuning as if you put a capo at the third fret of a normal guitar (e.g. open strings are G-C-F-A#-D-G). It has a much shorter scale length, typically 530-560mm, compared to the Torres 650mm scale, or even the period 625-635 scale. Italian Terz guitars were tiny in size, whereas Viennese Terz guitars adapted the Stauffer model, with its pronounced upper and lower bouts, to the smaller scale.
Tranposed Terz Music
Even though Terz guitar is tuned three notes higher, you play ordinary guitar music on it, except it sounds a third higher than written. Music written for normal pitch guitar may sound strange at the higher pitch of a terz guitar. Most people do not realize that a normal guitar in fact sounds an octave lower than the music is written. Because the Terz guitar sounds a third higher than the music is written, the guitar parts for duets with Terz and Normal guitar are written in different keys to account for the transposition. For example, if Guitar 1 - Terz is A major, Guitar 2 - Normal is written in C major. The Terz guitar in that case is actually playing in the key of C, although the music is written in A. Dr. Buckland was able to find several previously unknown Terz works by finding duets with mismatched keys, off by a third.
The advantages of a guitar with a root a third higher than a normal guitar with a capo are easy to see. A capo 3 reduces the number of frets available by 3, so that the highest note that can be played at the 12th fret is C# instead of E. The capo is confusing, since the frets are no longer at their original points, for example the 12th fret is no longer a point of reference, whereas a Terz guitar maintains the original frets. Modern editions of 19th century guitar music which claim it can be played with Capo 3 on a normal guitar are often not realistic, given the often frequent 12th position jumps and other idiomatic fingerings.
Terz Guitar Strings
The Romantic Terz Guitar was used for classical music and strung with gut strings, though today Nylon can be used instead. La Bella makes strings today specifically for classical / romantic Terz guitar, though I found their 2001L strings work fine as well. This web site has a section on Terz Guitar Gauges. DO NOT tune your normal guitar a third higher - this will cause too much tension and can damage your instrument. A terz guitar is 56-57cm scale, and even so, it still often requires lighter strings. M. Ophee sells string sets of very light gauge, so that you can string a 650 scale guitar as terz if needed - this is useful if you have an instrument not in service and need to play a couple of terz pieces but don't want to buy a terz guitar.

from https://www.earlyromanticguitar.com/erg/terz.htm

You could use a capo on the first, second or third fret and slacken the strings to get concert pitch with lower tension. And the frets would be closer together so less stretching required.

Kindly keep us informed; some of us are not so far behind you. - Stevo

Uptuning (I need some advice)
 

You should go to GSI…Guitar Salon International, and look at Wolfgang Jellinghaus Torres 77 (lower bout 11.7 inches and scale length 610 mm), or La Canada 17 or 17A (lower bout 13 inches and scale length 640 mm). Very nice guitars, I have the La Canada 17 Maple back and sides, and love it.https://uploads.tapatalk-cdn.com/202...b30533a60c.jpg
https://uploads.tapatalk-cdn.com/202...d9e4fbc026.jpg

Increasing tension that much is more likely to pull too much belly into the top-- south of the bridge, if not a challenge to bridge attachment. I used an online string tension calculator to find that you will be increasing total string tension by 40%. Play around with it, and check my work. Link below.

I used these inputs for the calculator, which may or may not reflect your setup of a 3/4 size guitar, which I know nothing about, so I used more (toward) conventional sizes inputs.

Scale length, 630mm. String gauges, .043"to .028 (a preset in calculator, I forget the in between gauges, but all standard.) Tension: 83.9 lbs at standard tuning.

Change to tuning G2, C3, F3, Bb3, D4, G4. New tension, 118.7 lbs.

http://chordgen.rattree.co.uk/tensiontool.php#

Since the OP has a 580mm scale, (580/630)^2*118.7=100lbs. This would be calculated with regular tension strings like d'addario pro arte nylon.

I’d look for lower tension since you mentioned arthritic hands. Email Strings by Mail. I’m sure that they would know the lowest tension.

Not sure about the numbers but Dogal Diamante felt very light.

I have a 3/4 size guitar that I tune up a fourth from A to A. I use the A,D, and G strings from a regular set of strings and tune it normal tension. For the higher three strings, I use the G, B, and E strings from a regular set and tune them up a fourth. So my guitar is tuned A-D-G-C-e-a . It is very playable and fun to play. I have tuned it this way for years and it has not broken.