Walnut Guitar Back
 

What do you guys think of this walnut back? It's kind of like a top with severe run out. The two pieces look very different in color under most lighting, and when shifting under the light the lighter color side will flip back and forth.
And what about the grain pattern? What part of a log, and how cut, would give that pattern? Would there be any drawbacks to that?https://uploads.tapatalk-cdn.com/201...17b4639479.jpg

That looks like flatsawn with pretty significant runout. The flatsawn doesn't bother me, but I don't much care for the runout.

Walnut is a nice wood, one that I've used for backs and sides. That particular piece wouldn't be my choice for a guitar back.


The "V", or "cathedral", grain is a telltale sign of flat sawn wood. It will expand and contract across the width more than a quarter sawn piece would, making it, potentially, more susceptible to cracking.

The top is under greater stress than the back, which is why minimal runout is structurally required for tops and is less of a structural concern for backs.


Despite the obsession that many have for wood type and configuration, one can make a nice sounding and playing guitar out of nearly anything. "Nice sounding" is, of course, subjective.

With all the work that goes into making a guitar I would never use flat sawn wood of any type because of the expansion and contraction issue related to humidity changes that Charles mentioned: the chances of it cracking at some point in the future is much higher than quarter sawn. Every single flat sawn Brazilian Rosewood back I've ever seen that had some age to it was cracked.

Thanks for the replies and info guys. I really appreciate it. This was a shipped to the store, not seen until pick up thing. I brought it home anyway but this one will have to be returned.

What the OP’s guitar? Is that a J15 like mine I posted about in other recent thread?

It's a J-45 Studio.
I returned it. I was turned off by the excessive runout and concerned about the grain pattern. But I have a different J-45 Studio in the house and really, really like it.

What is runout?

Maybe more than you wanted to know but a good explanation can be found here: http://www.lutherie.net/frankford.runout.html Quite interesting.

solid advise given from a Trade School Carpenter with 45 years of experience
 

Plain sawn, also commonly called flat sawn, is the most common lumber you will find. This is the most inexpensive way to manufacture logs into lumber.