I forgot to bookmark this thread for replies so missed the 'brass plate' and 'sanding the pocket' ideas...not the best IMHO
I concur with the other here and a lot of 'experts' out there. As C1 pointed out, most guitars like this have one, many should do. The 'shim' is particularly small too.
Her is a pic of my strat which is shimmed and clearly shows the 'gap' produced (only evident on the treble side, so only seen if you look for it).
I forget what I used for this ship, possibly wook, maybe a shaved down icey pole stick (ice cream...you know the things)...this is perfectly adequate, quite hard and will compress to shape a little (unlike brass and such).
But this guitar is an exception to most...the bridge...
Here is a new pic of the bridge which most people would consider to be an extreme float on a fender. It is much like the setting Jeff Beck uses and this guitar is devised for this kind of play. Also, because I had gotten quite used to the Kahlers which have even more range than a floyd, silky smooth, does not lift the string and will bend to any extreme should one wish...certainly more than any strings could possibly survive. The main cool thing you can do with the 'up bend' capacity is the 'flutter'...or some of satriani's things...the two string up bend in always with you, etc...
I could not find the JB set-up pic, Dan Erlewine features a complete measurement of JB and SRV guitars and others in his book and guitar player mag and elsewhere.
A more typical floating bridge on a strat is pictured below...
You really don't need a whole lot of room back there, your bridge block might even stop you before you get anything much further (my bridge block is tapered, but big up bends is not the reason to my set up).
Some people 'tune' their tremolo systems to...I forget the vid I have hear about that, but if you experiment enough with your gauge of strings and all that...you can get the B string to up say a minor third or something musically useful. Would take a bit of mucking about of course to get everything right, shim, saddles, height, intonation...but for many this is worth it. You can only really get this kind of thing with shims...at least to get to that stage.
If you want to do guitar work, this book is a gold mine..."Guitar Player Repair Guide" by Dan Erlewine (3rd edn)...not just for repairs but complete setups and a whole range of expert advice...
Ok..got the book out...lets see, page 163...
There is a section following on full sized shims. If you have a bench sander and the skills to do it properly, he show you how...he suggests mahogany, set the neck up with a conventional shim, measure that thickness, attach a thin piece of wood to another flat piece and use the sander to perfectly match the angle of the entire neck pocket, redrill and fit.
However, that is a lot of work really for something that you wont really see. Shimming the entire pocket with a flat shim is far more invasive that angling the neck perhaps 1mm at the back and far less of an effect.
But I have used all kinds of things for shims, typical shims are wet and dry sanding paper, perhaps folded one or twice and only on the body end of course...tilting the neck. Leo even considered this a feature of the guitar and eventually devised the ill fated 'micro tilt' mechanism (though not the greatest idea, a shim is better) so that it can be adjusted with a screw. Walmoth has a really neat side adjusting shim in some of their necks I believe.
Personally, though on fenders the effect is slight, I like a bit of a back angle to the neck. It is probably a result of playing a gibson for 25 years perhaps which has a significant neck angle and it took a while when I went to fenders to get used the their flatness and low bridge.
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Out of 'interest' perhaps is my current project whcih might be considered an 'extreme' shim...
Of course as I am building this guitar, it does not need a shim as I am having to rebuild the entire neck pocket. The angled back bridge is to accommodate the arch-top bridge but not that different than you might find on a Les Paul. You can see I had a full sized lift of 5mm plus an angle of about the same at the back to get the required angle with a fender style neck. No normal guitar with matched parts would need anything like this.
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Adding a full sized flat shim is not really teh way to go and there is no real benefit from using brass...though it is as good a materia- to make a shim out of. A very thin slice, say 5mm wide at the back is a fine shim. If you use a wider shim, it is likely to require shaping into a bit of a wedge.
While we are on shimming, often neck pockets are less than optimal and the sides of the pocket may benefit from some kind of 'shim' to make sure there is no possibility of movement. Dan's idea of screen mesh as both a shim and to provide grip is a good one. The use of sand paper has a similar effect, the grit will grip into the neck and prevent any movement once screwed down tight.
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It is easy to convince oneself what is 'best' or 'perfect'...this is the bane of the perfectionist which I admit I suffer. That is not to say that there is not a few superior methods or solutions to problems or achieving goals. But it does leave many to the mercy of people pedalling their own ideas or products over an elusive and likely subjective notions...the guitar world is full of it of course...'tone' and all that.
An example is this very thing, by tilting back the neck, you will get a better break over the bridge saddles and potentially 'improve tone' and intonation and such. Don't forget that once any adjustments are made like shimming, you will need to totally re-intonate the guitar.
Many fender types are set up far to low and flat to get the bridge to work properly, but this could apply to any guitar.
But the thing is to experiment...this is one of the great things about fender type bolt on necks, you can do almost anything to them and it is reversible!
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Clearcoating...lol..well, that is the factory finish. Again, don't be 'sucked in' tothe oiled finish is better thing. It can feel nice and certainly far easier (the main reason for it's popularit dressed up as being better) than painting to get a nice finish if you want that look. However, any finish that allows the wood to 'breath' as some tout this kind of thing, also allows the wood to absorb. A clear or painted finish will protect the guitar from absorbing moisture and if you think about it, intrinsically keep the wood inside 'dry'. An oil finish not only can allow moisture in...but itself is absorbed into the wood, deadening the air of the pores with a heap of 'gunk'..ooops, oil...LOL.
It's not a bad thing, but there is a lot of BS about it, largely to hide the real motive that a painted finish is difficult and to do well requires equipment, environment and skill to achieve.
My new guitars back and sides are plastic, so...no finish at all, must be good! The top will/has a clear finish that will look a bit like oil, but in reality is a clear varnish that is sanded back to look 'natural'. This will ensure that it is well protected, and if I could get inside the guitar, I'd be protecting that side too!
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But hey, it is a nice look and really, these things make little difference. One of the nice things about this forum is that it tends to cut through a lot of the BS and fetishism that is an intrinsic part of guitar lore.
The wolfgang is a nice guitar, but what were you thinking getting a fixed bridge on an EVH guitar LOL. The fixed bridge thing, along with through body stringing and such is so 2000...I sense the trem is making a comeback...all those memebers who have blocked their trems might have to consider the kinds of mods you are doing here themselves...