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Hello folks, I know I have asked this question in the past and it has been brought up by others, but I just want a final opinion. At our local lumber store, there are a few boards of hemlock with killer bear claw and quartered as quartered can be with amazingly tight grain. I'm really thinking about buying some and cutting it up for soundboards as I wanted to used bear law Sitka. Thanks everyone!

Quit thinking about it............ do it!

The problem with sawn planks is that you don't know which way the invisible grain is running. If it's short the top could be substantially weakened.

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Old growth, shmold growth!

Well I'm no master at seeing run out or anything but these boards are long and looking at the side the grain runs straight along most of the boards 10+ feet long

You cannot detect runout by looking at the growth rings on the edges of a QS board. If it were spruce you could determine runout by looking at the resin canals, but hemlock does not have them.
Your best bet is to split a sliver off of the corner on both edges. The reason you need to check both edges is that if the tree had spiral, the runout will be more pronounced on one edge. Assuming either edge can be joined, you should always pick the edge with the least runout to join together.

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John

The grain I'm talking about you can't see. You have to split the board.

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Old growth, shmold growth!

I see what you mean. I will check that out

You can see it without splitting the board if you make a 5$ investment in an inexpensive loupe and use it to look at the flat sawn side of the quartersawn board.

That's a good idea. I was actually thinking about getting a loupe anyway. I'll start seeing if I can detect runout without splitting it. If I can it would have saved me purchasing a $25 perfectly vertical tight grain Sitka (which I strongly suspect is Douglas Fir) for brace wood.

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Old growth, shmold growth!

"Splitting" also can be done by starting to tear off an even less than 3mm thin splinter from the edge. No big damage on a plank at a lumber store, but maybe your local tonewood dealer would not be happy if his customers ripped off splinters from his top wood.

I'm assuming this is Western Hemlock we're talking about, not Eastern? The Western I've tested follows the usual rule that relates the density to stiffness along the grain for soft woods, so you can work with it on the basis of density with some confidence. That is, if it's about the same density as Sitka or Red spruce, you would make it the same thickness you'd use for those woods. The Eastern hemlock I've looked at was more like a hardwood: 'way denser in relation to it's stiffness than most softwoods, and based on that it would be a poor choice for a top.

If one was to cut a small sample off each end of a billet, big enough for a top, and the grain pattern was similar at each end, would that not be an indication of runout or lack there of?

Depends on the kind of runout. If you did that you could see if the grain was vertical at each and which would tell you if there's any twist. I'lltry and dig up some pictures to inicate what I'm talking about.

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Old growth, shmold growth!

Okay, here's a couple of braces as seen from the SIDE of the brace. The ends of the grain show the vertical grain annular rings (though you can't see them.)

The one with multiple splits shows the direction the grain is running in. As you can see, it is slanted and "runs out" the top of the brace. You can't see it from the top, as it's invisible, and you usually can't see it from the side. These braces are creamy white on the side because of the perfect vertical grain, otherwise you would see light and dark blotches or lines as the annular rings intersected the sanded face in places, but the dark blotches or lines wouldn't correspond to the direction the invisible grain is running. This type of grain runout presents a possible weakness to the brace as the brace is more likely to split along the grain. I've seen braces fail where they've popped along these weak lines.

The brace that I split and prepared myself from a billet splits right along the center.

If you picture these as tops, the one with runout will reflect light darker on one side of the guitar than the other.

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Old growth, shmold growth!

Douglas fir should be easy to identify. The smell is very distinctive.

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John

kinda musty like an old attic?

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Old growth, shmold growth!