'73 Takamine F360 truss rod nut
 

I was given a Takamine F360 (ser.#73110054) that was in pretty sad shape when I got it. Took it in to a luthier to see if we could make a player out of it. It turns out that other than some cosmetic issues it is in pretty good shape except that the truss rod adjustment nut is missing. Curious if anyone here might have specs (bore size, thread, length, etc.) or might know where to look, or who to ask for such info.

Have you contacted Takamine directly or an authorized repair station?

Surely the luthier was able to work it out whilst you were there

Steve

Have not figured anything out yet. Luthier said he had it pretty much narrowed down to 3 possibilities, but with no guarantees. Thought I would peruse the net a bit and see if I can narrow things down a bit before I start ordering random parts and hoping they fit. I have sent an email to Takamine support with no reply so far. I have posted on a couple of guitar forums and registered for a couple more. Nothing so far. I will hammer on this until I get results or give up. Thanks for responses.

I don't understand. He can't reach inside the sound and try threading different nuts on it?

FWIW I also have a 1973 Takamine F360. It's about 2 months older than yours. I took the adjustment nut off and measured it. It's got a single action truss rod and it's metric. It's takes a 5mm hex fitting and is 30mm in length. HTH.

"73 Takamine F360 truss rod nut
 

He did try what he had available. Today after some more discussion the luthier I have been working with ordered 3 nuts and is confident the one of the 3 will fit. He is thinking that the final fix may require removing some material from the neck block and coming up with a spacer, but he is confident that it is doable. It will take some time, but I will post the results here.

Careful. It's not a dovetail joint - or even a mortise/tenon joint. It's a butt joint with 5 wooden positioning dowels. When I had mine reset the luthier had to do the "slip block" variety. You cannot remove the neck without sawing it off the body with a Japanese pull saw.

solved
 

found a direct replacement truss rod nut at: blackdogmusic.co.uk
M6 x 1.0 thread
28mm long - 9mm dia.
5mm allen head drive.
I have about $200 into the restoration and couldn't be happier with the results. Very nice player.