Intonation Out on A String only?

[Aaron LaBoon]

Hello

I'm a first time poster to this forum, but have read it and Frank's blog for awhile now.

I have a question that seems like it could be addressed by you fine folks. I have a 1966 Martin D-18 that has had alot of work done to it. That I know of: the neck has been reset at least once, the bridge has been moved (if not replaced), the saddle has been shaved, and the frets have been dressed. When I got it the A string was extremely flat past the third fret. I changed to 3 different string brands thinking that the strings were the culprit. Not the case, all of the other 5 strings tuned up and intonated just fine all the way up past the 14th fret, but the A string was still bad. The first 3 frets are golden, and I can play cowboy chords all day long, but as soon as I move up past the 3rd fret it all gets shot.

I took the guitar to a repairman who said the bridge was in the wrong spot. He made the proper measurements and moved the bridge and still found the A to be flat and exhibit the same symptoms as before. He then built a "shelf" to try and accommodate for the flatness at the bridge. This helped a little bit, but I still can't play it past about the 4th or 5th fret depending on the chord I use.

So, I ask you guys. What could be the culprit? Has anyone dealt with anything like this before?

Here are a few pics for reference:

[Bill Martin]

Yours does look a bit different from the standard...

[Rob Mercure]

I don't know about the better cared for comment - my Martin, a 1979 model, has been a working instrument "through hell and high water" and doesn't look a lot diffferent. But it truly sounds great and too often I play Martins, and other instruments, that have never been broken - they sound like "showroom floor" - which equates to sterile and lack of character to me. When I saw the instrument, barring the intonation,etc. issues, I thought "here's tool that's been worked hard and truly loved as opposed to admired." There's a famout quote from Pete Townsend that I is too "adult" to be quoted here but it's to the effect that that too is to be played and not polished.

This is to say nothing about the other issues but I'm much rather have a ragged looking instrument with a rich broken in sound than a shiny perfect sterile wooden box. I didn't buy my guitar for it's resale value and perhaps too many folk do (nothing personal about your tastes Tim - general comments.).

Rob

[Matthew Lau]

The neck is probably on wrong.
The bridge isn't in the right place, and I doubt it's original.

Could you give use a full frontal shot including the nut?
It would probably give us better info regarding what's going on.

And yes, I agree with everyone else that it's probably the bridge is placed wrong in relation to scale length.

[Jeff Highland]

If all the other strings are Ok then the bridge placement is ok
probably something screwy at the nut end but I doubt anyone will be able to tell without it in hand and with that silly saddle shelf removed