Truss nut help

[Big Jim]

I was given a poorly put together thin line semi hollow body telecaster kit. I got it straightened (loose neck pocket so the screw holes were drilled crooked causing the strings to be off center) and set up pretty nicely. Only problem I want heavier gage strings (seriously I think they are 7s) and I can’t figure what the truss nut key should be. The headstock says Legacy but I can’t find anything on line with that name and style logo that’s a kit. Has anyone built one of these that can help. Guy said it was purchased about 8years ago

[Big Jim]

Can’t see in clearly probably cause I’m old

[curtisa]

Isn't it just an allen key? It will either be an imperial or metric-sized one.

[Big Jim]

I tried both, every size around there, but I’ll try again

[curtisa]

Maybe there's something stuffed into the head of the nut that's preventing the key from engaging properly - some grime or general flotsam?

[henrim]

Hard to tell from the picture. Maybe you could try to take an other shot in daylight and try to get your camera to focus properly on the end of the truss rod. Without a clear picture it’s all guessing.

The paint has worn around the slot so someone has tried to do something there. Probably with a wrong tool. Maybe the allen key slot has stripped? Or it once was a protruding hex head that has broken? If it is a slotted nut I can’t think it would be anything else than an allen key slot. 

And there’s nothing adjustable looking on the other end of the neck? With the hole in the headstock It would be odd if there was but worth checking.

If the nut is stripped it may be hard to fix without removing the fretboard. But like said a focused picture would be a good start.

[Bizman62]

If there's extra particles or other stuff preventing the allen key to go fully down, a crochet hook might help. Or even a paper clip partially straightened and the very tip bent to an L shape.

Truss rod nuts can be a pita if they've been abused. Using a hair too small key (like a 3/16" key in a 5 mm slot) and not pushing properly down to the bottom can deform the opening of the slot and bypassing that can be difficult.

After cleaning the head try measuring the depth of it. The actual hex slot is about 1/4" or 6.25 mm deep and the housing of it is some 3 mm proud, plus the length of the hole in the headstock. Use a thin pin to find out the max depth and find the biggest key that goes as deep. Some penetrating oil like WD40 might also help.