When to Shim a Neck??

brunogio

New member
I have a MIM strat that I picked up in April and just got around to setting up on my own. I'm no expert but can do truss rod adjustments, swap pups, and set up the action. Before I bring it to my tech I thought I'd try some things out with it and try to get it playing the way I like.

It's a 94 if that is any help in identifying it. It came with a vintage tremolo with the bent metal saddles with Fender stamped on either side.

In this particular guitar, I lowered the action down all the way and still notice the action is a touch high on the high E. I prefer the action at the 12th fret at around 1mm and this is bit more like 1.5mm or maybe more. There is very little neck relief as well just enough to notice. Also there is no buzzing on the frets.

Is this a good case to shim up the neck? If not, what other tricks are there to try to get this to be a real player?

thanks
 
Re: When to Shim a Neck??

never, visit a good luthier to check and work on the heel if possible
 
Re: When to Shim a Neck??

1mm to 1,5mm on a vintage radiused is just plain nuts....
You'll need a feather to play it.
Nothing wrong with shims.....just another dumb myth from the E Johnson mad school....rubberbands, semitight screws...and so on.

Shimming a neck will increase the tension, make the guitar more loud....that is if your neck is any straight, and with that low action it better be good.....which most MIM's are not!
 
Re: When to Shim a Neck??

By 1mm I mean the string sits 1mm above the 12th fret. That's pretty standard low action from my experience and the way my local tech sets up all the guitars I've brought to him. I also see the same rule of thumb in one of my reference books for guitar setups so I don't think this is out of line.

I'm not too enthusiastic about shimming the neck and just wanted to hear from others on the topic. All of my other guitars are set neck so I don't have this issue with other guitars obviously.

I also have a replacement bridge Wilkinson vintage bridge which I'll probably toss on there as well. Not sure if that will help or not but I believe it an upgrade at any rate.
 
Re: When to Shim a Neck??

Hi guys! Just stopped stopped by to see what you're all up to.

Anyways, regarding shimming Fender style necks: If the little allen screws that adjust the height of the individual bridge saddles are sticking up to high and rubbing against the palm of your picking hand when you play that's often a sign that the angle of the neck needs to adjusted by shimming the neck. Shimming the neck will bring the fingerboard closer to the strings and usually makes the action to low at first so you'll want to then raise the action.

I think shimming the neck (when it's appropriate) tends to improves the tone of most Fenders. Because the individual bridge saddles need to raised afterward shimming the neck, the string tension is increased a bit and the angle of the strings behind the individual bridge saddles is a little steeper after shimming, which causes the strings to be pressed more firmly against the saddles. The result is usually better tone with better sustain.

Lew
 
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Re: When to Shim a Neck??

Playability is more important.

I did take the router to a body's neck pocket to correct the neck angle. There was an improvement in sound over using a shim (hardly surprising). I'm not sure it's worth the risk, though. It can be a tricky route job and it's easy to hack into the side of the pocket. For a small improvement in sound.

I suppose messing with the neck's heel is an alternative, but only after you decided this neck will be on the for the rest of the guitar's life, or after you determined that it's the neck that is "off".
 
Re: When to Shim a Neck??

i only shim a neck if the saddle screws are maxed out in one direction or other.

for example i put a neck on one of bodies, and the string height was super high, and the saddles were almost all the way down, so i put a small shim and the string height is normal, and the saddles are in the middle.

occasionally you need to shim the neck not for height but for pitch, as it needs to be close to parallel to the strings.

ive seen a couple of shims that are metal, which would be better than paper, you want a firm mechanical connection between the body and neck
 
Re: When to Shim a Neck??

I've shimmed many a neck. If you're trying to gain a half of a millimeter, all you're going to need is a piece of thin cardboard, like a piece of a business card that is 3/8" wide and as long as the heel is wide.

The cardboard compresses nicely as the neck is tightened and all will be well. Keep in mind that paper is made from wood, and does transfer vibrations.
 
Re: When to Shim a Neck??

Playability is more important.

I did take the router to a body's neck pocket to correct the neck angle. There was an improvement in sound over using a shim (hardly surprising). I'm not sure it's worth the risk, though. It can be a tricky route job and it's easy to hack into the side of the pocket. For a small improvement in sound.

I suppose messing with the neck's heel is an alternative, but only after you decided this neck will be on the for the rest of the guitar's life, or after you determined that it's the neck that is "off".

I was wrong, I meant "neck pocket" but wrote "heal"! Sorry.. Wrong angle inside the neck pocket causes problems that some guys try to solve with cardboard shims..
Shims kill sustain and tone because the neck (heel) loses full contact with the body wood (neck pocket) - that's what a luthier told me...I have no experience with shimming...
 
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Re: When to Shim a Neck??

Shims kill sustain and tone because the neck (heel) loses full contact with the body wood (neck pocket) - that's what a luthier told me...I have no experience with shimming...

I don't think that's necessarily true. It sounds logical - but as usual, actual reality is different than your luthier's theories about it.

When appropriate (to correct an incorrect neck angle) and when properly installed, a shim improves the sustain and tone despite the fact that it creates a small air gap under the neck heel.

Having owned a few 50's and 60's Fenders I can tell you from experience that as often as not, there's a factory stock paper shim in the neck pocket of many (if not most!) vintage Fenders.
 
Re: When to Shim a Neck??

Thanks Lew!
So you think paper (cardboard) is the best shimming material?

I had a slightly wrong neck angle in a strat... payed a visit to a lutihier to convert a 3-bolt neck joint (70's style) to a 4 hole and that guy did some minor work on the pocket also and then I asked him about the shimming...
I can tell you this- the guitar sounded really good before and after the procedure..not a big difference soundwise.. he really did the job on the pocket angle btw..
 
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Re: When to Shim a Neck??

I don't think that's necessarily true. It sounds logical - but as usual, actual reality is different than your luthier's theories about it.

When appropriate (to correct an incorrect neck angle) and when properly installed, a shim improves the sustain and tone despite the fact that it creates a small air gap under the neck heel.

Having owned a few 50's and 60's Fenders I can tell you from experience that as often as not, there's a factory stock paper shim in the neck pocket of many (if not most!) vintage Fenders.

Again. I took a Roadstar body that needed a shin. I used it with the shim. I routed the neck pocket to have the proper angle without a shim. Sound improved.

As far as I recall early Fender shims are sheet metal, not paper. And some early Strats and Tele are dogs :)

I also don't buy into "paper is made from wood hence it transports sound like wood" theory.
 
Re: When to Shim a Neck??

Never seen an old Fender with a sheet metal shim. The shims I've found in the Fenders I've owned and worked on have been some kind of very dense paper product. I've seen similar material used as the front and back cover of old notebooks. Here's some pics of factory installed Fender shims. I've seen both styles - the black and the reddish brown. A piece cut from an old credit card works well too - that's what I use these days. I do think that a guitar would probably sound best without the air gap under the neck that a shim causes, but the reality is that Fender guitars often need a shim to get the neck angle right - and if you get the neck angle right so that you can raise the bridge saddles that's good for the tone too. Like I said, installing a shim will raise the neck and move the fingerboard closer to the strings. You'll then usually raise the individual saddle height to compensate and that increases the string angle behind the saddles which presses the strings more firmly against the saddles. Makes the guitar sustain and sound better usually. Lew
 
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Re: When to Shim a Neck??

1 mm action at the 12th fret is ridiculous. I hope that's at least with heavier strings, otherwise you'd have to tap everything since any picking would be too hard lol
 
Re: When to Shim a Neck??

Well turns out the neck doesn't need shimming after all. I have re-set the bridge heights and the guitar plays fine. I am going to straighten out the neck a little and then should have the thing working even better.

Just needed to experiment a bit more. Not owning a bolt on strat for a while now proves that I needed to approach the setup a little different than my Gibsons.
 
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