Shim.. or No shim..

[dmin77]

What are the pros and cons of shimming a JM neck?

Is there a significant difference in the feel of the guitar when it's been shimmed?

I have a local luthier trying to sell me on the idea so I wanted to ask for some advice here..

[Axolotl]

Nothing wrong with shims IMHO. I'm sure most peeps will agree. Keep in mind that Jags and JMs were designed with a shim in mind, as most if not all of them came with shims from factory.

It will allow you to elevate the bridge with fairly low action thus increasing the break angle between the bridge and the tailpiece. This will prevent strings slipping from the saddle and also will increase the sustain a bit. The tension of the strings will be slightly higher on the first frets. If you have some buzzing in the first frets, shimming the guitar may help to get rid of some. In my experience, I feel when shimming a guitar the sound is more open and clear.

Some people say that shims take away the sustain/resonance from a guitar because doesn't allow full contact between the neck and the body. I don't think it would be an audible difference. Besides now you have those fantastic stew mac shims that are full pocket size.

I say go for it, a shim is an easy "mod" that can change noticeably the feeling of your offset and it's easily reversed.

[daemon]

I just went through this recently when I put a gold mustang bridge on my '94 JM. I loved the lack of rattling, but the action was super high, and when I lowered it I was getting buzzing. So, I bit the bullet and bought one of the StewMac shims. I had a hard time paying that much for a thin piece of wood, but it was worth it. As soon as I put it on everything fell into place. I had great action and no buzzing. I didn't notice any other differences. So yea, shim away, shim all day, if you want to.

[JVG]

I'll join the shim party! Some people get wayyyy too worked up about the shim issue, carrying on about loss of resonance and such. I've never forked out for a purpose-built one...always just used thin cardboard. Works a treat. Sounds fine.

Give it a go

Cheers!
J.

[Larry Mal]

I've come to the point where I pretty much shim any Fender type guitar that I have.

[soggy mittens]

pro-shim-life.

[rkharper]

pro shimmer here, none of my screwed in necks are unshimmed.

[Larry Mal]

Especially since Stew Mac now makes those perfect (and expensive) shims, you can make your Fenders have a break angle like what Gibsons have built in and all the advantages of that angle with the ease of use that a bolt on neck provides. The best of both worlds, and I see no reason not to do it.

[dmin77]

Thanks!

I'm gonna shim my necks and see how it feels.
I was hesitant because I didn't know it could be undone so easily.
Indeed, pretty inexpensive to grab a couple from stew mac, too.

Thanks again!

[Mad-Mike]

Whatever gets it to play the best. All of my Offsets are not because they get lower action and play faster/smoother that way.

[AWSchmit]

I would vote that anything with a separate trem and bridge system (Jazzmasters, Bigsby's, etc.) could use a shim in the neck. I usually only shim those kinda of trem equipped guitars though. Unless I'm having an issue with clearance at the bridge or with pickups or hardware that would make higher strings over the body advantageous. Otherwise for tele's and the like I leave them unshimmed. For shim material, since I have a nice little supply, I use thin strips of copper sheet. They are nice and hard, so I know they won't compress and any thought of "sustain loss" can be minimized.

[OV7]

A Stew-Mac 0.5 shim made a huge difference in playability and set-up for my Warmoth. I couldn't get the action right to save my life beforehand.

[spacecadet]

AFAIK all original JM's came factory shimmed. (I'm sure there were a few that weren't, either because they just turned out not to need it or because Fender forgot.) So they're made that way. Even the AVRI's were made that way, because the originals were. Fender finally changed this on the AV65's, which are meant to not need shims. Though some people probably still do it; on mine I'd need to raise the bridge and pickups WAY up if I shimmed it, though.

Ditto for my CIJ, which was clearly made to not need shims. My CIJ with no shims has a taller bridge and pickups than my AVRI with three shims, in order to have the same string height over the neck.

So basically, pre-AV65 American Jazzmasters really should always have shims - they're intended to. Any others, probably not, but if your action's too high and you can't get it lower, a shim is probably the answer.

[zepset]

Definitely use one if the setup requires.

[dmin77]

Definitely use one if the setup requires.

Ordered the Stew Mac shim.. looking forward to experimenting.