Here's a handy calculator that gives you string gauge based on your scale length, desired note and tension.
I used it to figure out what gauges of steel string to use on a concert uke and it worked out great.
nice tool Korrigan but i have no idea what tension i should have on the strings so it makes it a little hard to use. i have a 500mm scale 6 string neck i want to use but no idea what to string it with...
It's a matter of taste but I prefer about 20lbs on each string, makes it easier for me to play slide (I tend to push down too hard) and I don't have a problem fretting with that high of a tension.
Usually, short scale gits need heavy gauge strings to tune to the right pitch. Some big string supply store will carry short scale strings(Tenor Guitar).
Mental exercise: capo a standard scale guitar at the fret closest to 20", what are the notes for each string now...which are closest to GDg. use those strings.
thanks JL thats a great help.. my 500mm scale length guitar neck is about the 5th fret on my yamaha pacifica. i use 10 to 46 on that so the smaller scale should be ok with 13 to 56... which is the same set but drop the 10 and add the 56..and should be around the same tension i hope... can always tune it down a half step to e flat....
The capo at say the 5th fret, represents a much higher set of notes. Trying to tune to that pitch would most likely break the strings.
A heavier gauge string(11's or 12's) on a short scale will require less stress to tune to the right pitch.
No, a capo at the 5th fret doesn't change the string tension, it shortens the scale length, which is what the OP is looking to do.
I wasn't saying that a capo changes the tension. I said those notes at the 5th fret are higher than the regular tuning and trying to tune a short scale guitar to those notes would most likely break the strings because of the higher tension. It's hard enough to tune to regular pitch on a short scale with regular strings. That's why most people use a heavy gauge string or get Tenor strings for short scale guitars.
25.5" scale EADGBE capo at 5th fret gives you ADGCEA at the same tension
19.10" scale (5th fret of a 25.5" scale) same strings tightened to identical tension gives you the same ADGCEA.
So I would select strings #6, #5, and #4 ADG and drop #6 to G for GDG at 19" or 20" inch scale and this does not put higher tension on the strings.
Putting a capo or fretting any position on the fretboard only changes pitch and not string tension. The tension when tuning to the set pitch stays the same. The tension on the strings of a 25.5" scale and a 20" scale are just not the same.
I was wrong about about the strings being too tight. I had it backwards. The light gauge would be flabby on the short scale unless tuned to the higher pitch like you were talking about.
My Dulcitar and the 3-string PVC Bass I built are 28" scale with regular guitar strings. They are both tuned to Drop C. Any higher would make the strings too tight and possibly break. Any lower and the strings get flappy. These are light gauge and that helps for longer scale, but a shorter scale needs heavier gauge for the E tuning or just get the right strings for the scale you have.
You could use regular strings on a 24" scale, but 20" scale is going to be a big problem trying to get to the E/A/D/G/B/E tuning. This is why they make the short scale/tenor guitar strings, electric guitar/regular strings and longer scale/baritone strings.
Fender made some 24"scale guitars, and some as low as 22.5". The lower scale guitars always had the heavier gauge strings to get the tuning to pitch.