setup issue?

[Justin Carvitto]

I've had a mandolin of respectable quality for 5 years. Just recently there's been a tuning issue. I"ll tune up the G's, on the nut just fine, but by the time I fret the C note on the 5th, the strings are .25 off. It sounds aweful. This is not the issue with the other strings open or fretted.

What I've done to try and solve the problem:

1. Adjusted the bridge matching up the octave's on the 12th for the G & E
2. Adjusted the height of the bridge.
3. Changed the strings.
4. Checked the tuners/tailpiece
5. Checked for any separation along the neck and fingerboard.
6. Checked for sinking in the top.

could there be anything hidden that I'm not thinking of?

nothing has worked yet.

Justin

[Michael Lewis]

Is the nut chipped under the G strings? Is the saddle worn and in need of freshening up? It's hard to tell from here.

[Ivan Kelsall]

Do the G strings go sharp or flat ?.One of the first things i'd do is to check for worn or 'sprung' frets. By 'sprung' i mean a fret that's sligthly come out of it's slot. Get a 12" steel rule & place it on edge along the fingerboard & look for any frets in the 5th fret area that might be up or down. If a fret has lifted only slightly at one end,it could affect the strings there without affecting the other
strings.I had a similar problem with an old pre-war Banjo years ago.It was so old,the neck wood had dried out & the frets were begining to loosen. It's only a long shot but worth checking. If a fret is unduly worn,then the string fretted at that position,will most likely touch the next fret along & note sharp.
If you find that you can't solve the problem yourself,then pay a visit to a good luthier.If the mandolin is as you say,of 'respectable quality',then it's worth it. These guys know of things we've never even thought of - good luck,
Saska

[Justin Carvitto]

It was the saddle.
Touched it up and put new strings on it.
Good as new.

Thanks Lewis.

justin