String Buzzing on frets 15 - 21. Neck shim needed?

Open strings = no buzz
Fret String from 1st fret - about 12th fret = no buzz
Fret string beyond 12th fret = The strings hit and buzz on all frets from about 15th on down to the last fret.

Think this is a Neck Shim job? If so where does the shim need to go in the neck pocket? T'wards the nut end of the neck or t'wards the bridge end?

The action is set at 5/64 at 15th fret Low E to High E, if that helps.

Thanks,
J:

I'm thinking a shim would make the problem worse. How much neck relief do you have?

To follow what ChicknPickn said, I just fixed a similar problem by straightening the neck (removing relief) and raising the action a bit afterwards.

Alot of Fender style guitars will develop a rise in the fingerboard in the tongue area---I have a tele like that,gonna have to level frets 15-21.

I'm thinking a shim would make the problem worse. How much neck relief do you have?

I would have to check when I get home but I set it per Fender's Spec on Fender website using capo's and feeler guage.

Also, this is a partscaster and the neck has a 2 way truss system, if that helps anything.

J:

I would have to check when I get home but I set it per Fender's Spec on Fender website using capo's and feeler guage.

Also, this is a partscaster and the neck has a 2 way truss system, if that helps anything.

J:

In that case, you might consider a couple of things:

- As Warddix suggested, adjust the truss rod to lay the neck pretty much flat, then work with saddle heights to find a better action

- Check fret heights. One of the best tools ever created for this is a little steel trapezoid sold by Stew-Mac. When you've set the neck flat, you span three frets at a time with the tool, checking to see whether it can rock over a high fret. You move the tool along the neck one fret at a time, checking left-right-center as you move along the neck. You may be shocked when you see how many frets are not as they should be. I know I have been.

- Also, as Refin pointed out, you may need some "fall off" at the upper end of the fretboard. I don't know if you do your own fret leveling and have the tools, but all of these things can turn a nasty action into a nice player.

http://www.stewmac.com/product_images/1lg/3770/Fret_Rocker_Detail.jpg

Thanks everyone,
I'm afraid I'm probably going to have to have a leveling on the frets. This is a Chinese neck on the partscaster. I really want a maple fretboard so I might just get another neck then do a leveling if needed.

J:

I concur with Chicknpickn and Warddix. This is NOT going to be corrected by shimming the neck. I've seen this many times, it's really just an effect of too much relief (bow) in the neck, and at that particular spot it's often thought of as a "tongue-hump."

I guess I'm just repeating what ChicknPickn sez:

Try the trussrod first - it's just an adjustment, no new parts, and you already own this neck.

A fret leveling, while a good idea and certainly an option, at this point may not go far enough to do what's required AND leave any meat on the higher frets, depending on how much of a hump it is.

SO, to fix the issue you have, my FIRST adjustment would be to the trussrod in an attempt to straighten the neck, removing any relief/bow (or at least, adjusting for less). IF you are able to straighten the neck, you are halfway home. There are a few threads here to help you do that properly, do a search.

The BAD NEWS is, on some axes, adjustments to correct the bow where you are experiencing it - right over the tongue area - are not effective, and may just give you an "S" shaped neck. If that's the case for you, work the trussrod to get the neck as FLAT and LEVEL as possible, and then try fret leveling. You may find yourself simply filing down the height of the frets at the 16th and above - you just want to make it so that the tops of ALL the frets are basically level.

Often, while I'm at this, I will actually "overfile" those first half a dozen frets (22 - 16), creating a bit of a "drop off" towards the bridge, as ChicknPickn referred to in his post - IF there's enough meat (height) on them.

NEXT, If you have successfully straightened the neck and and leveled the the frets, it now may rattle almost everywhere, equally. That's because the trussrod adjustment doesn't lower the "tongue-end" of the fingerboard, it actually lowers the NUT end to get the neck level. That's an easy fix - just raise the bridge.

IF it still rattles everywhere AND you have run out of adjustment at the bridge and cannot raise it any farther, THEN you might want to shim the neck. Unlike shimming to LOWER the action, you will want to place the shim at the "open" end of the neck pocket, farthest from the bridge, to create a shallower neck-set angle to RAISE the action.

So, MY steps are: 1) adjust trussrod to remove relief; 2) adjust action at bridge and test; 3) fret leveling if desired/required; 4) adjust action at bridge and test again; 5) shim IF necessary.

AND, don't count on a replacement neck solving all your problems with no worries. MOST new necks are gonna require SOME adjustments right out of the box, too...