Rickresource Rickenbacker Forum

I've got a J Mascis (the purple one, not the new white) signature Jazzmaster that I've been working on. It came stock with a Tune-O-Matic bridge so individual saddle adjustment is not an option. The issue I'm having at present is that the action is higher towards the body, and I would prefer it to be more even, and would also prefer to leave the neck as flat as possible. I know a lot of offset-waist Fender guitars came with shims, but these were reportedly paperboard; I would assume paperboard would influence the resonance of the guitar, so I'm looking to do a hardwood shim. Most of my local repair shops are using card stock as well.

Does anyone have experience and advice relating to shimming the necks on these guitars? Is finding the right size shim a process of trial-and-error, or can I simply eyeball (or measure) the action at the neck joint and craft my shim based upon that measurement?

Better than paperboard would be a piece of aluminum or brass shim stock (available at hobby and hardware stores in the "K & N" display). This can be cut with scissors; I'd buy the .020" thick. One of these on the forward end of the pocket will handle most cases of lowering the action. Or, you can buy some .101" and stack several. It doesn't take much.

JMs aren't particularly known for resonance and/or sustain, anyway, although the TOM helps.

Thanks, Paul; I had not considered metal shims from the hardware store.

I think I've been blessed with a particularly resonant Jazzmaster; the TOM is certainly a factor in that, as are the larger strings, and the neck is such a tight fit that I also have to use a bit of force to set it in the pocket. If held upright by the neck the guitar stays attached even without the bolts.

Would you choose a metal shim over hardwood? I guess metal is generally more resonant than hardwood...

There's even a third choice--.020 acetate or styrene or ABS, all available under the Plastruct brand name in hardware and hobby stores.

Shimming really seems to help with these guitars. I have an AVRI Jag that I took apart and put back together with a shim and the difference in the neck angle made all the difference. It really took the guitar from rarely being played to a regular player...which lasted all of a week before I snapped a bone in my left elbow...but that's a different story.

What did you use for the shim, Matt?

DriftSpace wrote:What did you use for the shim, Matt?

Probably due to inexperience and basing it off what had been done before on other guitars, cardstock.

jingle_jangle wrote:JMs aren't particularly known for resonance and/or sustain, anyway, although the TOM helps.

What's the difference between a Jazzmaster and a Banjo?

A Banjo has more sustain!

elreydlp wrote: What's the difference between a Jazzmaster and a Banjo?

A Banjo has more sustain!

Not mine.



Novak JM-180 in the bridge and a Novak JM-V at the neck; Warmoth modified Mustang bridge. Amazing combination of screaming hot tone at the bridge (out-screams my Les Paul even!) and that shimmery sweet Jazzmaster neck position tone. None of the typical Jazzmaster ********; I couldn't tolerate that. Commissioned by the guitarist from Surfer Blood, now my favorite guitar.

The difference is, if you leave a Jazzmaster in your car with the door unlocked, someone will steal it, while if you leave a banjo in your car with the door unlocked, when you come back to your car, it will be stuffed with a bunch of other banjos, in addition to yours*....


*ruined variation of a joke heard from John Hall....

paologregorio wrote:The difference is, if you leave a Jazzmaster in your car with the door unlocked, someone will steal it, while if you leave a banjo in your car with the door unlocked, when you come back to your car, it will be stuffed with a bunch of other banjos, in addition to yours*....


*ruined variation of a joke heard from John Hall....

But still a good one...