matching the chayotiance of a four-piece top

[Bob Hammond]

Hello,

In my pile of odds & ends, i found a a very nice piece of spruce that's 5-3/4 wide. I think it could become a good soundboard. As I recall from the Olden Days, that four-piece tops were built up to full width on the lower bout by gluing on the offcuts from the waist as 'wings' at the widest span of the lower bout. Now, the trick was to orient the pieces so that the chayotance of the grain matched. So as I recall, the offcuts were flipped, e.g. the offcut from the waist on the treble side was flipped over and then glued to the lower bout area of the bass side.

Is that how it is done?

[Bob Gramann]

All you have to do is look away for a second and you won’t be able to remember which piece is which in which orientation, so you’ll have to hold it in its intended place and rock the top back and forth to see if the piece belongs there. What you say seems to be right, and with careful marking of the pieces before cutting, you might be able to get the right piece in the left spot, but you’ll have to test it in the light anyway. These rotations used to be easy in my mind. Not any more.

[Randy Roberts]

You got it right Bob, "flip" it to the "other" side.

The other Bob is also right. Whenever I did this, I always had the straight edge of the cut out waist piece to abut to the straight edge of the opposite side lower bout, and the "bump out" of the cut out protruding out beyond the rest of the board to help keep things straight in my mind. With a 4 full length pieces to glue up, all the edges will look the same.

Mark them up however you want to to keep them organized as to who is face up and who is face down and which ends are up or down, and if you are anything like me, you will have 3 glued up right and one going wrong.

Check them with good lighting before you glue them up.

This can also be very handy for backs, not just to get the extra inch or so you need from a not quite wide enough board, but also for visual effect.