Shimming Electric Bolt-On Necks?

[David Edward Helmer]

At work there are a good amount of Electric guitars and basses that have the bridge saddles jammed to the bottom with high action. There is some plastic shim stock here. Can I just use this plastic to shim these? Considering what I have at my disposal here, this seems like the only option. I did one on a mediocre bass and it worked. Acceptable? How will this affect tone and sustain? I am more of an acoustic guy so, I am just wondering what you all think and feel about it.

Thanks!

[Mirabeau Laing]

Use whatever you have if it works. Any tonal differences I would think would be so small that most people won't notice.

[nathan clark]

A non tapered shim at the bridge end of the neck pocket (mortise) is fine for cheap guitars.  If a customer needs this sort of work and they seem fussy (detail oriented) or the guitar is somewhat valuable then I have the conversation of full-pocket tapered shim vs. non tapered shim at the very end of the neck pocket.  I mostly just use scrap hardwood for the small shims at the end of the pocket.

I use math when I change neck angles.  Even with bolt on neck guitars it saves me time.  Here is the formula that I use for strat style necks:

Strat/Tele style heel:
Maximum shim thickness at end of mortise = (xz)/w
Where:
w = distance from fret directly above neck/body joint (opening of mortise) to the bridge
x = length of mortise
z = distance that the neck has pulled forward as measured at the bridge

[Robert May]

I don't like any gaps, so I prefer full pocket tapered wood shims. I make them out of old pallet wood. I double stick tape the wood onto scrap, set it at an angle, then ride my router/sled over it. I don't have a belt sander, or I might use that instead.

[John]

The rise at the end of the fingerboard happens on old Fenders sometimes, shim or no shim. I've use wood veneer for this job probably 90% of the time. I've routed the pocket flat glued in new wood and recut the neck pocket (usually to avoid the dreaded back of the pocket shim) and I've even installed a few tilt adjusters. The rule is: if the action at the last fret is higher than the 12th fret you've got room for a shim.

As far as sustain goes, the theory is that if the neck fits flat in the pocket the guitar will have more sustain. If I notice the wood on the neck pushing out where the screw goes into it I use a counter sink bit with a Tele knob on it to counter sink the hole a bit. The idea is that less is more and the neck sits flatter in the pocket. 

My customers tell me they like the way their guitar feels after a setup. I've never been told that their guitar had more sustain or less sustain.

So while I get the theory, and I even believe in it (a little bit) Shim a neck if it needs it, playability trumps theoretical sustain.

[Peter Laine]

I've read several posts in different places where tone is discussed, they maintain you need to sand all paint out of the neck recess and assure wood to wood contact, ( they also are saying to remove paint from the pickguard cavity)   Myself  I have always used brass shim stock for this but I'm not sure what is the optimum width

   anybody think it is acceptable to carve away the actual wood of the body to effect the change in neck angle?

[Jeffrey L. Suits]

Youtube, "bridgeport neck pocket"  I can't get the url to paste, here.

[Allan Lang]

Here's an easy fix with no gaps, use painters blue tape and make a step-up shim. Neck pulls up too much, use three strips on top of each other closest to the heel, then two, then one, there's your shim with no gaps. Sometimes only a slight tilt-back is needed so use two, then one. You can even cut the tape and make a custom small shim with strips.

[Jeffrey L. Suits]

Actually, "angling neck pocket", gets you right to it.

They're not using a Bridgeport, it's a pin router.

[Peter Laine]

Very interesting,  is this something you would do on a vintage strat?

[Thomas James]

IMHO - No. I would use old factory shims, or something that can be removed. 

[Ned Knepp]

Disclamer: I'm an acoustic person and know very little about electrics.

Why wouldn't you mill out the pocket if it needed it? That's pretty much what happens with an acoustic neck reset. I mean, material is removed to return the instrument to playable. I can't see why anyone would want to return a playable guitar to an unplayable condition by changing something that isn't visible. What am I missing?

[Thomas James]

I was considering vintage value and original condition vs. basic problem solving. Old shims can sometimes solve the problem in the vintage way. Obviously, an owner can do what they choose. I would be concerned about chipping out old finish as well. Strictly thinking vintage guitar show crowd here.