Intonation off on

[Caleb]

My StewMac Campfire kit mando is turning out to be a really nice instrument. The only issue I'm having is the A course strings. They will be in tune while open, but then when I fret anywhere in the first position it will be a bit off. I've been tuning them again while fretting at the 5th fret, which is working to a degree, but I'd rather not have to do that. Is there anyway to fix this?

I saw a mando player at a retreat last year who had a small wad of yarn up under the A course on the nut to keep them intonated. It didn't look so great, but it was working.

Any advice?

[Crowder]

Is it possible that the top of your bridge is on upside down? The compensation might be off for that reason.

[Caleb]

Is it possible that the top of your bridge is on upside down? The compensation might be off for that reason.
No, don't think that is the problem.

[Paul Hostetter]

If the nut slots are right, and assuming you have real A strings on there (not a second set of E strings - it has happened!), that leaves only the saddle compensation.

Reversing the bridge wouldn't make a lot of difference, assuming it's a standard Gibson clone. Adding wads of anything will certainly not help. Zillions of other mandolins that do work make it clear there's a small detail that's not right. Your task, should you choose to accept it, is to find out what that is.

The center blue image is the "right" way. Sometimes it works better flipped end for end as in the upper magenta image, and sometimes the bilaterally symmetrical one, pale blue bottom, works better.

http://www.lutherie.net/mandolin.bridge.compensation.3.jpg

As you can see, the A and D don't change no matter what.

Check your string gauges for starters.

[Caleb]

Thanks for all the help. I'm off to do my detective work.

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[Clyde Clevenger]

Sounds like a nut ramp problem. The nut has to be ramped down from the fret board side. First nut I made looked beautiful, but I didn't know how to cut the slots properly and I made a mess of the tuning. Only cost me a little pride to get it fixed.

[Caleb]

Sounds like a nut ramp problem. #The nut has to be ramped down from the fret board side. #First nut I made looked beautiful, but I didn't know how to cut the slots properly and I made a mess of the tuning. #Only cost me a little pride to get it fixed.
I hear you on the pride thing. #I finally broke down and took this thing to a shop for a setup, besides what I'd already done. He made it play a lot better, and the A course wasn't doing this at first, but seems to have only started recently. #And I'm using the same kind of strings as when he did the setup work. #But.... I did try some other strings in between the setup work and now, and the lighter tension of the Thomastiks (which sounded terrible on this instrument) might have thrown things out of whack? #I've got a set of Black Diamonds in the chute for next string change, and that very well may throw things off even more. Man, these little instruments sure are picky! Guitars are way more forgiving!
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[Michael Cameron]

Caleb,
# It's that dangedole short-scale : )
c

[Caleb]

Oddly enough, this issue seems to be working itself out. The more I play this thing the more it seems to settle down and sound/play sweeter. I'm still having to tweak the A course every now and then, but it's better than it was. These really are strange little instruments and I'm not going to even pretend to have this all figured out. But maybe newly built instruments take time to settle down. I'm learning...