Book matching tops

[irish blues]

Can you explain book matching for guitar top. Maybe I am too anal, but it bugs me when I see a top where the seam does not line up. It would seem that if you take a section, split it in two, it would match up better. Does the grain change alot through the thickness of the wood?

[TSL]

Hi Irish Blues,

There are a lot of variables that affect the way a piece of wood comes out when doing bookmatching. The first is the quality of the saw and blade being used and the quality of the milling equipment. The second is the skill of the woodworker making the cut. Thirdly is the piece of wood. Lets start by assuming that all are ideal and work backwards from there.

Figured wood, flame or quilt tends to grow slowly. What this means is that the figured pattern in the wood changes dramatically in a small amount of space. So in as little as .025 of an inch the shape of a figured pattern could change or vanish altogether.

Say you want to bookmatch a nice maple board that is 1.5 inches thick (after milling) 8 inches wide and 20 inches long. Your finished pieces will be 0.75 inches thick minus the thickness of the blade. But you still have to account for blade flutter and the slight radius the blade will have making an 8 inch thick cut. Now you have to mill the cut surfaces to make them smooth. In doing this you are removing more wood from the center of your cut. Altogether lets say the thickness of the blade .025 plus another .025 for milling is removed. That would make the total amount of wood removed from absolute center .05 inches At this point the change in the grain pattern can be quite large.

This leaves you with two boards 0.7 inches thick by 8 inches wide and 20 inches long to bookmatch giving you a bookmatched piece that is 0.7 X 16 X 20 inches, which is roughly large enough to make an electric guitar top. One way to alleviate the shift in the pattern is to line the figuring in the wood up by shifting the two boards until the patterens line up before gluing them together. In doing this the long ends of the boards end up offset slightly.

That's how it works in an ideal setting. In the best of conditions you still end with a lot of wood worthy of a good coat of paint instead of some stain and a few well rubbed coats of clear.

Hope that helps
Terry

[tom]

one other giant variable is how the woodis cut. if it is quartersawn(vertical grain) like most flame is, symetry is pretty good. some wood has a stronger napp to it so it will reflect light very differently depending which way you are looking at it. with bookmatching, the two halves have the napp running the opposite direction. if the wood is flat or slab sawn, like most quilt, the saw cut will take you through several year rings so you can have quite different looks on the two sides.

[AndyK]

I can go nuts obsessing about how the top matches, how the flames look under different lighting, etc, etc! I passed on buying several R8 flametops because their tops had strange flame pattern, or those verticle lines running through the flames (forgot what they are called).

Life would have been so much easier if Gibson stuck to goldtops only!! :D

[TSL]

Hi Tom!

And I was trying not to get too technical :eek: :D

Terry

[Barry]

I can go nuts obsessing about how the top matches, how the flames look under different lighting, etc, etc! I passed on buying several R8 flametops because their tops had strange flame pattern, or those verticle lines running through the flames (forgot what they are called).

Life would have been so much easier if Gibson stuck to goldtops only!! :D
Make sure always have to correct lighting and you will always have the top you want !!

[irish blues]

Thanks for all the info. I have a better understanding of what I am looking at and I will be less bugged about it......though I will still try to get the best matched top TA has to offer.