Truss rod issues, among other things. . .

[thearabianmage]

The background info: One of my friends, Alec, has this old Epiphone LP Studio (the thin model) that his friend had bought from new, trashed, then gave to Alec randomly one day. It sat around in my other friend's room for a couple years getting trashed even more until Alec decided he wants to keep it.

The situation: Alec wants me to fix up his LP (fret-job, electrics over-haul, hardware over-haul, 'the works' basically) So I just got started on it tonight. I had given the frets a little rub with my leveller to see if there are high and low frets and noticed a slight concave in the middle of the neck (the straight-edge is literally about 1mm away from the frets at its furthest) so I started adjusting the truss rod when I noticed it was really loose. Really loose. So I got my trusty needle-nose pliers to see if it would jiggle out or something. . . And with almost no effort, it did. Well, part of it.

The problem: There seems to be an extension on the end of truss rods that screws on to the actual truss rod. This extension is threaded on one side (the side in contact with the rod) and has the allen-key slot on the other side. In order for me to screw this part on, I have to turn it to the right, and the piece fits nice and snug on the truss rod. But in order to fix the concave, I need to screw the piece to the left.

Can anyone guess what happens when I do that?

If there's a way to fix the truss rod, great. I'll then straighten the neck, give the thing a level and crown, and Bob's your uncle.

If not, should I carry on levelling the frets and just make sure that when I am done, they are all level despite the very slight curvature (which shouldn't make any difference once the frets are levelled, it's just that some frets would then be taller or shorter than others, and I thought something like that would cause problems. . .)

I've read that necks should be slightly concave (I've also read that it's down to the player's preference to have it slightly concave or absolutely straight)

Is it a lost cause? (If so, then why?)

I'm just a bit confused and any help would be very much appreciated!

Cheers y'all

[markb]

Here's some vids walking you through the setup process for a Lester. There's a written guide on the "lifestyle" section of www.gibson.com. If there's that much relief I'd think the truss rod needs to be tightened. Tightening the rod pulls the neck straighter and you seem to be describing a large forward bow.
Go easy with truss rod adjustments. Do a quarter turn at a time, bring the strings back up to tension and measure. Cut string ends make good feeler gauges for this kind of adjustment. You want about .011" or so gap between the first string and whichever fret is halfway along the unsupported part of the board. The videos should cover this much more easily than I can describe it.

http://www.expertvillage.com/video-series/2744_setup-les-paul.htm

[thearabianmage]

Here's some vids walking you through the setup process for a Lester. There's a written guide on the "lifestyle" section of www.gibson.com. If there's that much relief I'd think the truss rod needs to be tightened. Tightening the rod pulls the neck straighter and you seem to be describing a large forward bow.
Go easy with truss rod adjustments. Do a quarter turn at a time, bring the strings back up to tension and measure. Cut string ends make good feeler gauges for this kind of adjustment. You want about .011" or so gap between the first string and whichever fret is halfway along the unsupported part of the board. The videos should cover this much more easily than I can describe it.

http://www.expertvillage.com/video-series/2744_setup-les-paul.htm

Hey, thanks. I'm not exactly sure I explained my situation correctly, though. Cheers anyways!