I have been playing guitar now for almost 20 years, just for my own I joyment and jamming with friends not on a professional level. Due to an unfortunate set of medical circumstances I am left me with Limited range of motion in my upper body and hands making it very difficult to play full-size guitar.
Seeing what CBG Nation is doing has given me a chance to build a much shorter scale and smaller body guitar. I have a baritone ukulele the body is just to long and to thick to fit my needs.
The baritone uku is a guitar with out the E and A strings. By dropping the E string from the ukulele I have a short scale 3 string guitar. By masking a solid body and adding electronics I can make a CBG with a length of around 20 inches from nut to tale.
The short, 19 to 20” neck the pitch thing means I must tune to “DGB” gives me a short scale guitar with open G tuning. Knowing as much about music theory as I know about rocket surgery my question is. What do I need to know to be able to use GDG tabs?
All you need to do is figure out what gauge strings to use for your desired tuning and string tension.
This is a great tool for that: https://wahiduddin.net/calc/calc_guitar_string.htm
But if you are going to be playing from GDG tabs then why not tune to GDG instead of DGB?
If you want to use GDG tabs, then you need to tune your instrument the same way i.e. GDG - DGB won't work. Baritone uke tuning is D G B E. You can take off the low D and tune it G D G - the standard uke string gauges won't be ideal, as the middle and the high G will be a bit tight but it might work.
I built a 19.1" scale slide guitar with a humbucker to play at my computer station. It is currently tuned to G2-D3-B3 with .042"w, .032"w & .017" strings at 13.1#, 17.0# & 14.7#. By experimenting, I found the low string tensions give an immense amount of sustain. When I was using GDG tabs, I changed the small string to a .022" tuned to D3 with 14.3# tension. In conclusion, according to my experiments, the shorter scale lengths don't require as much tension to have a long sustain.
The OAL of the guitar is 27" so it will fit in a Mandolin gig bag. Locating the pickup close to the bridge keeps the tone from being to mellow. The bridge is bolted to the neck offset. This is one of my favorite guitars and I wouldn't change anything. The teak top is re-purposed from an old sailboat centerboard. The rest of the box is red oak. And, the neck is cut from a re-purposed NASCAR engine shop table top.
G/D/G is simply 1-5-1. Meaning that the G is your root note, the D is your fifth note and the other G is the root at a higher octave. Using a D/G/B tuning is still a G chord being D-5th/G-root/B-3rd. So a D/G/B tuning is a G major chord. The G/D/G tuning is G without the 3rd. You can play it the same way, just having a 3rd instead of extra root.
You can use regular guitar strings on that scale, but you'll need to use heavier gauge strings to tune up to pitch.