Electric octave nut advice

[Uncle_Nate]

Howdy folks, I have a question that I was wondering if some of you could answer for me.
I'm building a electric octave mandolin with a 19" scale length. My question concerns the nut width and the string gauge.
Right now I have it planned out with a 1 1/4" nut width, is this wide enough?
I like narrow necks, but I'm afraid of the G course causing problems from heavy gauge strings being spaced too close together because of the nut width. Is that wide enough? Or should I go 1 5/16" or even wider? what's your opinion/experience?
Also, I was wondering about string gauges. Whats the thinnest I can go(once again, I am particularly concerned about the G course), without having floppy strings? For the sound/size I am going for, I would prefer as light as possible.
I would greatly appreciate any thoughts or opinions on the subject!
Thanks in advance,

My very best regards
-Nate

[Graham McDonald]

1 1/4" is narrow but doable. My standard is 34mm a bit less than 1 3/8" Pic is attached.

A 19" scale is pretty short for an OM and will need fairly big strings. You could just about use nickel wound mandolin strings and tune it as a CGda mandola at that scale.

There is a string tension calculator (http://www.mcdonaldstrings.com/stringxxiii.html) on my website which will allow you play around with different gauges and scale lengths. What might be useful would be to do a percentage comparison between the total tensions of a light acoustic guitar (.012" top e) and a light electric guitar set (.010" top e) which you should be able to do from the downloadable D'Addarrio tension chart. Then work out what might be an equivalent tension for an 22" electric OM compared to an 22" acoustic one ( which the tension calculator will give you), and then play around with gauges on the tension calculator to find what size strings will work on a 19" scale instrument. After that it is try it and see what happens.

cheers

[thistle3585]

Personally, I was not happy with a 19" scale OM tuned GDAE. I just couldn't find a G string that I was happy with as it was pretty floppy. Someone suggested flatwound strings, but I never got the chance to try them. The OM I am building now is 20.5".

[Uncle_Nate]

Thanks for the advice! That Solves my problems Graham. Greatly appreciated.
Thanks,
-Nate