Need Neck Advice - MIM P truss rod issues maybe

scolba · #1 02-11-2011, 02:10 PM

Hey Guys,

A while ago, I swapped with a dude here on TB my Mighty Mite Maple P neck for his rosewood MIM P neck. All things looked good at first...but I didn't look all that close and the project got shelved for a little while. Getting back into it again, and decided I needed to adjust the truss rod to flatten it out a little bit (was trying to solve some of the high action woes caused by a hi mass bridge). When I went to put an allen wrench in there, I realized, hey, I don't know what size. So I look down in the opening and don't see anything resembling an allen "hole". I just sort of see splines.

So my question is thusly. Is there just a nut that is missing there that can be replaced, or is the truss rod, and therefore the neck boned? If it is boned, I will have some more questions, but I'll wait for the first answer first.

Lesson learned on this one, thats for sure.

Thanks guys!

jimbilly · #2 02-11-2011, 04:34 PM

It should take a 3/16" allen/hex wrench.
If it's in there, you should be able to back the nut all the way out and lube the threads, -that's a good idea on MIM Fenders. If it only needs a little adjustment, it probably has a nut in there. I usually loosen it first, and loosen the strings too so as not to 'fight' the string tension while adding truss rod tension.

joeyl · #3 02-11-2011, 04:48 PM

also cranking the truss rod to lower the action caused by a higher bridge is a bad idea, most likely you need a neck shim. You should search on how to check the relief of the neck (that's what you use the truss rod for) and how to change the action of the bass.

scolba · #4 02-11-2011, 05:45 PM

ok, ill double check with an allen that size....i looked again w\ a better light and i might have been imagining things, but im not 100%

Thanks for the other advice...This is actually just part of what i am doing to try and get it setup. I have actually already shimmed it, and that somehow resulted in a little less of a bow, but there is still one that's more than i'd like...so thats why i was thinking the truss adjustment.

walterw · #5 02-11-2011, 06:18 PM

a shim would not affect the bow one way or the other.

if this is a mexi standard bass, you need a 3/16" hex wrench.

if it's a vintage reissue, you just need a big straight-slot screwdriver (and to take it off the body to get to the truss rod).

i like "offset" screwdrivers for this, they have much more control on vintage slotted truss rod nuts.

JLS · #6 02-11-2011, 07:19 PM

"Shimming the neck", seems to have evolved into some kind of an Urban Bass Fix-It-All, Myth...

bassbully · #7 02-11-2011, 07:26 PM

Gezzzzzz he was talking about adding a shim to bring the neck up some to offset the high action caused by the high mass bridge not to take bow out of the neck.You guys act like you repair fighter planes for a living

walterw · #8 02-12-2011, 12:16 AM

Quote:

Originally Posted by bassbully

Gezzzzzz he was talking about adding a shim to bring the neck up some to offset the high action caused by the high mass bridge not to take bow out of the neck.

Quote:

Originally Posted by scolba

I have actually already shimmed it, and that somehow resulted in a little less of a bow...

sorry, and thanks for playing.

Slackerprince · #9 02-12-2011, 12:24 AM

This is what you want:

http://accessories.musiciansfriend.c...ool?sku=360804

Indespensible, IMO.

S

scolba · #10 02-12-2011, 06:38 AM

Quote:

Originally Posted by walterw

sorry, and thanks for playing.

Yeah I wasn't very clear when I posted, sorry about that. I wasn't shimming the neck to try to and change the relief. The bridge saddles are as low as I can get them without actually touching, and the action was still too high, so I put in the shim. I realize, too, that it SHOULDN'T have any effect on the relief, but when looking down the neck before and after, I actually did observe a difference.

I figured since I was asking about the top of the truss rod, I didn't need to mention the whole scenario, but next time I will def paint a clearer picture.

Thanks for the link to that tool! I got a gc gift card I need to burn!!

Edit: whoops...thats MF, not GC....apparently I can't read this morning. Sheesh.

JLS · #11 02-12-2011, 08:49 AM

Yup, you did it right--there are just so many boneheaded ideas about what, "shimming the neck", will fix, that my cranky evil twin will take over, and post, sometimes...

scolba · #12 02-13-2011, 03:01 PM

thought i'd follow-up. I got the appropriate allen, and i was indeed imagining things. there was a nut in there to adjust, so i got it all measured out and adjusted appropriately. Sadly after all that, the action is still too high for my taste, so off to a bridge search.

thanks for all the help guys! I'll have a new thread started shortly for the bridge search.

walterw · #13 02-13-2011, 03:18 PM

Quote:

Originally Posted by scolba

...i got it all measured out and adjusted appropriately. Sadly after all that, the action is still too high for my taste, so off to a bridge search.

OK, now that the neck is straight, if you can't get the height where you want it, don't go looking for bridges, shim the neck.

the shim (credit card or thinner, please) would go at the bottom of the neck pocket, towards the pickups; this should put the neck angle in range for the saddles to go where they need to go.

looking for another bridge is a wild goose chase.

scolba · #14 02-13-2011, 03:27 PM

It actually already is shimmed...about 1/4" thick of an old gift card...EVER so slightly thinner than a reg CC, all the way at the bottom of the neck pocket.

My only option, i think, which is really ok w\ me after reading the High mass vs standard bridge thread, is to go with the Fender Deluxe bridge...pretty much the only thin one that i can find that is string through.

JLS · #15 02-13-2011, 05:33 PM

Quote:

Originally Posted by scolba

It actually already is shimmed...about 1/4" thick of an old gift card...EVER so slightly thinner than a reg CC, all the way at the bottom of the neck pocket.

My only option, i think, which is really ok w\ me after reading the High mass vs standard bridge thread, is to go with the Fender Deluxe bridge...pretty much the only thin one that i can find that is string through.

I'd try thicker shim stock, before I spent $ on a bridge. Seriously.

You really are at the point, where this is called for, and appropriate.

Hopkins · #16 02-13-2011, 06:14 PM

What bridge is on it now?

scolba · #17 02-13-2011, 07:33 PM

I'm not actually sure of the brand. It came in an allparts shrink wrap package, but there isn't a brand on it. It basically looks like a 201 but is string through.

So for a thicker shim, do I need to get something one piece that is thicker, or is it ok to stack what I have now with something thin, a trimmed business card for example, to start?

walterw · #18 02-13-2011, 08:52 PM

either is fine. you might also want to use a thinner shim in the middle of the pocket along with the thicker one at the bottom, positioned (with the aid of a straightedge) so that it supports the neck as well. you'd want the neck supported at both ends of the pocket and the middle.

if you like the idea of a different bridge for other reasons then sure, pursue that. we're only saying don't get it just because you can't get the height right.

Hopkins · #19 02-14-2011, 07:56 PM

Quote:

Originally Posted by scolba

I'm not actually sure of the brand. It came in an allparts shrink wrap package, but there isn't a brand on it. It basically looks like a 201 but is string through.

So for a thicker shim, do I need to get something one piece that is thicker, or is it ok to stack what I have now with something thin, a trimmed business card for example, to start?

If the saddles are the same size as a Gotoh 201 Then they are larger than the stock ones. If this is your case you can just swap out the saddles for the stock ones to get a lower action and not have to use so much shim.

tooloudalex · #20 02-15-2011, 07:28 AM

One thing I've found is that sometimes if you loosen the neck bolts near the body and tighten the other two (near the headstock) down tight it can sometimes (not always) help get that .25 mm your looking for.