Neck shim?

[mamm7215]

Hi all, I've got a bit of an action issue with my Cort C4Z. The action is a bit high for my liking-about 3/16 at the 17th fret from fret top to bottom of E string. Most setup guides say 6 or 7/64 is good here. Problem is my saddles are as low as they can go on E and G strings. Neck relief is about perfect: 1-1.5 business card thick when strings are held to straight edge at 1st fret and where neck meets body. Truss adjustments only get buzzy when tightened so my neck setup is as good as I can get it. The only thing I've not done is shim the neck in the pocket. My question: is this an acceptable fix and does it negatively affect the tone of the guitar? (ie: take away from neck/body mating for sound quality). Thanks.
Also, if it's ok to shim, what should I use? Bus. card-piece of wood....?
Thanks.

[62bass]

Some use a business card, or masking tape. I've used thin edging veneer or thin plastic or aluminium.. It doesn't seem to affect the sound.

[mamm7215]

I took a deep breath and dove in and it turns out there already WAS a small strip of I think vinyl (like seat cover material) about 3/16x1.25" and about the thickness of a business card. Not sure if it would've even affected the tilt but I cut a pocket template and shimmed about 3 business cards thick and that did the trick. Had to make a small relief adjustment but that seems to have gotten it. I may redo the shim with some old business cards I have made out of real wood (I'm in forest industry). Thanks for the replies.
M.

[62bass]

Glad it worked out. I've even used guitar picks in a pinch, sometimes cut pieces from a plastic coffee can lid and once fastened a shim from a slat on a discarded aluminium window blind.

It doesn't seem to change the sound a bit. Of course the purists will disagree.

[Easy Rider]

I'm no purist, but I did find that my bass lost some top end and sustain when I shimmed my neck with cardboard (shoebox lid). I left it on for a while, checking the tightness of the neck bolts once every week or so, to let the cardboard compress, but that didn't help.
I've now replaced it with some aluminum/aluminium (whichever you prefer) sheet and my bass is back to his old self again, no difference with the 'unshimmed' situation.

It may just be my bass, but I still think you should use a hard material for the shim (like metals and hardwoods) just to be safe.

[mamm7215]

Yeah, I'm of the same mindset. I'm going to remove the business card shim and replace it with a hardwood veneer business card I've got. Actual business cards made of real wood. I can cut a template to exactly match my neck pocket. Otherwise, the shim was just what I needed to get my action/saddle setup back. Finding the original shim in the first place leads me to think it was necessary out of the factory to get it to playable.

[jsh008]

I used a dime to shim a FJB, worked well.