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I’m working with plates that are just a bit too narrow to fit in the body outline. The top is cedar and the back is Honduran Rosewood.

I have been planning on adding wings to the lower bout from the off cuts at the top. Originally I was thinking that I would just flip the top part from the same side over so that the coloring on the grain lines matched up. As I thought about it I am wondering if under finish if this would make the joint visible from the reflection in certain lights. I have seen some tops where under light one side looks darker than the other and when you shift it the light and dark side look like they flip flop.

If I need to keep the grain orientation the same to avoid this contrast, I can just cut from farther up in the upper bout and keep everything oriented as it grew in the tree.

What is the proper way to do this?

John,

Cut out the profile and take the piece from the upper right and move it to the lower left and vice versa. Keep all pieces face up. this will put the runout in the proper orientation.

Steve

Thanks Steven. That makes sense.

Steve,

I don't think what you're writing is entirely correct (but not 100% wrong either - you just skipped a step).

You have three options:

Take from upper right and "slide" down to lower right keeping it face up.

Take from upper right and move to lower left but rotate 180 degrees while keeping it face up.

Take from upper right and move to lower left, rotate 180 degrees and flip.

(I had to make a prop to make sure I had it right - I recommend doing the same just to make sure!)

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The reason some two piece tops look darker on one half is because of runout. It appears dark when you look into the "end grain". If there is no runout, you can make the glue joint practically invisible

The procedure as I described will match the run out of the pieces. Without the 180o rotation, the runout will be opposite.

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http://banduramaker.blogspot.com

Here are a couple of Pics of the back and how I was thinking of orienting them.
Before moving them.

I have the blue on one side and green on the other.

Does this look OK or do I need to rotate them? Basically I just shifted one side top to the other side bottom without flipping.

Don't make it complicated. Take a piece from the outer edge of the right top, and use it on the right bottom. Don't flip it, don't change sides.

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The way you have it, if there's any runout, it will be in the opposite direction the way you've got it and show up as a chatoyance effect you're trying to avoid.

Woody B's suggestion is what I'd do (option 1 in my list).

Edit: my list is assuming a book matched top. Option 1 works in all cases.

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http://banduramaker.blogspot.com

Thanks everyone.

I'll stick with option one. I was going to do that for the top anyway just to minimize the variance in color contrast.

Yep - option one .. slide the piece down, same side, same side up .... works every time. I just did a piece of sinker redwood that way, and its so good that you think the joint is a half inch away from where it really is - you cant even find it without seeing the length mismatch at the end of the jointed pieces.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

All good advice on grain orientation. Frankly, it looks to me that you're going to route those wings off when you cut the binding channel. If anything, you'll have a very very small amount of wing left.