mettelus

BobF
This looks promising
 
http://stringtensionpro.com/

That is a cool site. I just walked through other for mandolin and it spits out tensions at the end after you choose length and tuning.

Excellent, it looks like this site will be a big help with my electric dulcimers. I had a bit of guess at the gauges on my baritone model and they are a little slack for my liking.

hi,
 
I think that I have some homework to do and see if I can do something, and play more bass or not!
 
Probably not ... I'm destined for keyboards!

Probably the simplest option to get a mandola more "centred" in D rather than C is knock a thou or two off the standard CGDA tuning string guages, tune to DAEB then it's trial and error until you hit on guages and makes you like. Or just get a banjo/mandola capo that fits the neck and capo up a couple of frets.

Octave mandolins in standard tuning are pretty good in D, but to put a C mandola into GDAE means going up quite a bit on string guage to prevent everything going floppy. You'd almost certainly need to widen the slots in the nut or replace it as well.

Calculating string tension is only worthwhile if you know what tension you are after and why. D'addario do give the tensions for their strings on a "standard" scale length, but that doesn't necessarily transfer to other manufacturers. Then there's perceived tension vs actual tension. It's the core of a wound string that takes almost all the strain, wound cores being generally the same guages as plain strings. The wrap adds mass and has a big role in how "tight" or "stiff" the string feels to play.

I appreciate the ideas. No I haven't emailed the company because I wanted to try and figure it out for myself if possible, but it looks as if it might come to that. If I could get my head around those calculations offered earlier I think I would have it down. Thanks StringMaster for offering to help. I can certainly send you what I know.
 
I put the J72s on the other night and I tuned it to DADG. It seems to be holding that tuning, but there are a few problems.The largest course is .049. That's a  large gauge for that instrument. The strings don't sit all the way in the nut, same goes for the next course, but they did tune to that and it sounds pretty good if you can get past what feels like playing high tension power cables on the first two courses. The action is a little high as would be expected. I would definitely need to do some work on the nut and action if I was going to keep this setup. As it stands, I'm seriously thinking that I might be able to go a few mm smaller on the lower courses...G to D is quite a jump. The tension on the neck is probably really high. I'm looking at what I could do with .040 on that lowest course same for the next onein taking the suggestion by tlw ...a lower gauge. The J72 set is .049 .034 .023 .014
 
Even with those limitations I like the way it sounds and I played it for quite awhile last night. If I mostly use the first two courses as a drone and play the rest.

I've never found a commercial set of strings that really works for me in DADGAD, acoustic or electric. Sometimes there's no real alternative to making up your own sets out of single strings. Costs more though :-(

Looking at D'Adarrio's loop-ended string range then for DADG (low to high) I'd probably start by trying something like
D=0.47
A=0.32
D=0.23
G=0.17 or 0.16

The overall tension may not be the same as a CGDA set, but should be pretty close I would have thought. Should fit the nut slots as well.

 
Thank you tlw.
I broke one of the .049's attempting to tune. The .047 probably would fit my nut better. I'm just glad it was the string and not the neck that broke:) 
 
I'm glad I found someone who uses that tuning here.