Fender neck issue...

[Jono Bolton]

I currently have a Mexican Fender Jazz, and the action seems pretty high to me, and there's a bit of a choking issue as well.

I used to have a Badass II on it, and had the neck shimmed to lower the action but without having a lot of fret buzz. I've since removed the Badass and put a more vintage styled Wilkinson bridge on it. I left the neck shim in and I have have to have the action quite high to eliminate any fret buzz. It's not too bad, but I'd like it as low as I could get it.

I tried taking the neck shim out to be able to lower the saddles, but there was still a fair bit of buzz.

It occurred to me the other night that the only thing I haven't tried is the truss rod. I bought the Wilkinson after speaking to BassBunny, who recommended it and said he didn't have to shim his neck.

I've done that thing whereby I fret the neck at the 1st fret, use my arm to press the strings down at the body end of the neck and measure the string height at the 8th fret, and it doesn't seem to be too high at all, but I also have a Fender set-up manual that my flatmate got with her Tele and has instructions for guitars and basses, and according to that, my action is about 0.5mm higher than Fender recommends as a comfortable string height at the 17th fret (Fender says about 2-2.5mm, mine is about 3mm).

First of all, does all that make sense? Secondly, would it be an idea to remove the shim and put a bit of relief in the neck? Roughly a quarter-turn clockwise? Thirdly, what size Allen Key would I need to undertake such a task? I didn't receive one when I bought the bass a few years back.

Any help would be greatly appreciated fellas.

[johnnylager]

I believe the shim should have just brought the neck up relative to the bridge, to prevent the saddles on the BA bottoming out, right? If this is the case, then as long as you are not at maximum extension on the grub screws on the Wilkinson saddles, you shouldn't need to remove the shim [is it a full pocket shim by the way?].

I set-up my Geddy Lee & KSD 704 Jazzes with very little neck relief [and I think Bernie Goodfellow did too, but don't quote me] so they were almost straight and bizzarely enough, I found this helped with getting the action down. I then got individual string height / intonation sorted to get as low as possible without buzz using the saddle grub screws. I don't mind a bit of clank though!

It may help to give the rod a tweak and only use small [1/4-turn as you said] increments [righty-tighty - lefty-loosey]. Some advocate loosening first to check the rod's working before nipping it up. I'm not being patronising, but don't risk your neck if you are unsure. No idea what size it might be though, some f***ed up imperial size knowing Fender...

Good luck mush...

[Jean-Luc Pickguard]

The truss rod is always the first thing to look at when a bass starts to feel different. - The shim isn't likely to change over time & neither is the bridge (unless bits are loose). The wood in the neck changes its stiffness due to the ambient humidity changing. Adjusting the truss rod counteracts that.

I'd put it back exactly as it was before fiddling with it and then tighten the truss rod about a quarter turn and and see if that makes it any better - if not another quarter turn until it does.

Pressing the first & last frets of any of my basses shows a gap of less than 1mm at the 7th/8th frets and they all play very nicely. 3mm would be unbearable for me.

At least on a Mex fender the truss rod adjusts at the headstock so you won't have to remove the neck.

[Jono Bolton]

Thanks very much guys. I'll have a look at the tweaking the truss rods. I tried to get a set of Allen Keys today but had no luck. I'm going to try Maplin tomorrow.

JLP, I think you may have misunderstood part of what I said. 3mm is the height of the E and A strings at the 17th fret when no notes are fretted, while Fender recommends that it be between 2 and 2.5mm. When doing the fret-at-the-first-fret-and-press-the-strings-at-the-end-of-the-neck trick, the height if the strings seems to be less than 1mm, leading me to believe that the neck is too straight.