Full pocket vs partial shim

[GretschWretch]

Thanks GW just not a fan, don't get me wrong, I can adjust and I have a couple covers on P basses as well as Jazz but it's not natural for me and just feels strange when muting, it forces me to play more forward than I like and pick articulation/mute/feel changes, I even cheat a little by positioning the cover as far back as possible while still covering the bridge...

I took into account your palm muting and recognized that the cover might pose a problem. But in some instances about the only way to prevent one's forearm from getting shredded is the cover.

 

[Turnaround]

Interesting that whenever these shim discussions pop up, whether due to saddles bottomed out, overly magnetic pickups, or whatever, the solution is always to tilt the neck. Why not just raise the neck? Measure how much higher the neck has to be to solve the problem and use a flat, not triangular, full pocket shim of the desired thickness; i. e. a dead flat shim. This will raise the neck but also will keep the neck in the same plane as the rest of the instrument.

There's nothing magical about the neck to body angle. So you can use a flat shim or a partial shim that is a lot thinner to accomplish the same thing. For a given amount of lift at the bridge, a partial shim need only be less than 1/3 of the thickness of a flat shim. A flat shim will show at the outboard end of the pocket, as will a tapered shim. A partial shim doesn't really show. This has a .015" shim:

 

[bassdog]

I tinker with both my parts basses and just added a partial shim to the PJ. I like the way the bass feels and plays with the neck angle changed very slightly.

I have done full shim on this bass before as well. I sometimes go no shim also. Just a tinkerer and a little bored at times. I switch necks around too. Currently a MIM J neck with rosewood board on the PJ and Allparts J neck with maple board on the J. Was the other way around last week. Carry on.

 

[Mrtoodamnsabre]

Got the bass back, a few updates

Cant even see the shim! It’s invisible, sounds great bust most notably somehow they banished the warble from the bass?

so final question is, basically i have another Sabre, an 84 with the electronics of a 79 in it, if I shimmed this bass could I theoretically get the pickups further from the strings?

 

[darwin-bass]

Shim on a micro-tilt neck? Why would you shim a micro-tilt? Needed to raise the nut-end of the neck? Thinking that the micro-tilt erodes tone if it is used to tilt the neck?

 

[darwin-bass]

Got the bass back, a few updates

Cant even see the shim! It’s invisible, sounds great bust most notably somehow they banished the warble from the bass?

so final question is, basically i have another Sabre, an 84 with the electronics of a 79 in it, if I shimmed this bass could I theoretically get the pickups further from the strings?

Lower the pickups. What am I missing here?

 

[mike buzzetti]

Wow everybody seems to be a luthier now LOL! ??

 

[Dave Leighton]

FWIW factory shims were very common on vintage Fenders.

Early 60's looked like this:

View attachment 4634030

Later 60's like this - and were in different colors depending on thickness:

View attachment 4634032

My 81' P came with the red one in the 2nd pic. I assume it was factory. No issues with the neck. Great medium to low action. Had an Ibanez Black Eagle when they first came out, 1976, and I pulled the neck several years later. It had a thin strip of bone, possibly waste from making a nut as a shim. No ill affect on the neck. My 2013 Nash J had a pick being used as a shim. I pulled that because it was unnecessary.

So I personally have not seen the partial shim being an issue. But I'm no Luthier

 

[BassyBill]

Wow everybody seems to be a luthier now LOL! ??

I expect the number of comments just reflects the very large number of bass players we have here on TalkBass, the big majority of whom take a healthy, active interest in setup and maintenance of their instruments and a very large number of whom have a combined experience of many years in such matters, applicable to a huge number of instruments, that they are willing to share to help out others with similar interests. I don’t really see any cause for cynicism or suspicion about it. It’s what the forum is for.

 

[Zooberwerx]

Got the bass back, a few updates

Cant even see the shim! It’s invisible, sounds great bust most notably somehow they banished the warble from the bass?

so final question is, basically i have another Sabre, an 84 with the electronics of a 79 in it, if I shimmed this bass could I theoretically get the pickups further from the strings?

If these guys really came-around on the second attempt as described, I’d give ‘em a shot provided all parties are on the same wavelength.

Riis

 

[DJ Bebop]

Interesting discussion in a way and I agree with other comments that the OP is a bit overthinking the shim issue - and maybe basing that overthinking on a misunderstanding of what's going on.

The comments about preferring a partial shim to get more original wood contact make no sense to me as the partial shim would pretty much ensure a "big" air gap in the neck pocket between the places where the neck makes contact with the body and the shim - so LESS contact overall. I guess that this is where the luthier's concerns on the ski jump come from as the neck bolts might pull the neck down to fill the gap, bending the end of the neck into a curve. I've seen that argued by several guitar builders/fixers... For example.
View attachment 4634083

...is that true or not... no idea but it sort of seems a bit plausible, sort of...

My personal preference based only on snake oil, mojo and an understanding of secondary school physics would push me towards a full pocket shim as that should maximise the wood on wood on wood contact area with vibrations being able to pass relatively unimpeded across the whole of the neck body joint and that FEELS more logical to me than a neck joint where vibrations are being transferred across two separate areas with an air gap in between.

Photos from a similar Google search showing the difference between a partial and full pocket shim - for avoidance of doubt...
View attachment 4634084

View attachment 4634085

So on a personal basis (and as the above caveat says, on the basis of personal preference and presumption) my leaning would be to a full pocket shim - and I know many, many, many very well respected luthiers prefer to shim that way so it's by no means an "inferior" solution like the OP presumes (and of course a similar number happen to prefer a partial - no biggie!).

So, yes, we're definitely in the way overthinking it territory by the OP. So if the neck angle is now such that the magnets can be adjusted to stop magnetic interference and wolf tones I'd probably say that the OP should be pleased with a job well done and stop worrying about a "problem" which they seem to have invented in their own mind.

My old school fav, not by me though...

 

[GregT]

All I know is that I've used partial shims for over 50 years with no issue. I've used credit cards, two picks cut in half, plastic, wood, and anything else that worked. Never, never ever had an issue. It is what I'll do for the rest of my time on this earth if it comes up again. It works and it works well. If you make it big enough, and the screw goes through it, it would cause the opposite of a ski jump, if you think about it! "If it's not fixed, don't break it!"

 

[baxter_x]

Here it is, the video I was trying to find where Roger Sadowsky and Michael Tobias talk about neck shimming. At 13:46:


They both explain, neck shimming never ever changed the tone of any intrument.

 

[claudel]

Old school?

 

[Bodeeni]

for me the biggest thing about shimming the neck is string height off the body. And, that is a personal preference. So I might shim the neck differently than someone else. After doing most of my own tech I do not remember shimming because of the pickup height to the strings, but definitely pickup height off the body. I personally do not like everything to flush and like the strings and pickups a bit higher. I might shim if I could not adjust the pickups, but for me it is all different reasons.
As for the ski jumps, most happen behind the neck joint at the taper around fret 14, but I have put a small bend in the very front of a neck with a skinny high shim all the way forward and over excessive front screw tension. Actually bending the heel. Not easy to do, but. Backing off the forward screws a half a turn or moving the shim back corrected it.

 

[-Asdfgh-]

Old school?

View attachment 4636371

Make sure you use tone cardboard.

 

[mongo2]

Make sure you use tone cardboard.

Yesterday I used a few combinations of a couple of white Amazon gift cards and black Amazon gift cards as a quick shim. The white gift cards sound brighter than the darker sounding black gift cards and one each of black and white in combination have a tone that's just right.



YMMV

Seriously, I did use a couple of white Amazon gift cards as flat shims and they work fine. They're a bit smaller than the neck pocket so it looks like the neck is floating above the body. No problems or tone change.

 

[claudel]

Make sure you use tone cardboard.

Zig-Zag has the toanz, bro...

 

[bassdog]

I tinker with both my parts basses and just added a partial shim to the PJ. I like the way the bass feels and plays with the neck angle changed very slightly.

The tinkering continues. Removed the shim. I liked the way the bass felt and played but seems some clanking was part of the package. Not sure why that would be but didn't like it. I suspect just hitting upper frets a bit with the slight angle back created by the shim. Did slight neck and saddle adjustments. No more clank. Plays and sounds good like a PJ should. Sometimes a shim may be necessary, sometimes not. Carry on.

 

[JimmyM]

The tinkering continues. Removed the shim. I liked the way the bass felt and played but seems some clanking was part of the package. Not sure why that would be but didn't like it. I suspect just hitting upper frets a bit with the slight angle back created by the shim. Did slight neck and saddle adjustments. No more clank. Plays and sounds good like a PJ should. Sometimes a shim may be necessary, sometimes not. Carry on.

Ya, that's the one thing about shims...the perfect height and placement is really trial and error.