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In the post polling split vs. sawn bracewood, Howard pointed out that one splits to avoid runout, not to get quartersawn. Thought I would post these two pictures of a small brace to show the difference and why one would want to split bracewood to avoid runout.


On picture shows the end of the small brace. Looks like it would make an excellent brace. Can't wait to use this one!

But look at the top of the brace. Might not make such a great brace afterall. This isn't going to be as strong as a brace that had straight grain end-to-end.

Hope that helps to show the difference.

Yeah, but there's one more plane to be concerned with: flip the piece that's shot from the top
90deg so you're seeing the side. There can be runout in that direction too.

You are not likely to be offered wood so poorly cut. As Jim said, the real issue is with that third face, the side grain, which doesn't have any visual clue to the grain when sawed or planed. When split, the grain lines are visible to a close inspection. A magnifier can help.

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Build log

Alan: The brace end picture shows good quarter cut but still may be loaded with run-out.
Tom

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A person who has never made a mistake has never made anything!!!

I make sure i have straight grain one end to the other always as i mentioned in the other post. The picture you showed has runout running on an angle and that is not straight grain and should be avoided.

I am still having trouble with this runout thing. So in the picture above, since the grain is running at an angle with the sides, that is runout on that face. (This is also called short grain?) But we also need to be concerned about the direction of the wood fibers on the side faces in relation to the top and bottom faces, correct? And the only way to see this if you have quartersawn wood is to split it perpendicular to the end grain? Also, in neck wood, if you are laminating two or more pieces, do you have to pay attention to runout?

Thanks,
Scott

The grain lines can be perfectly vertical, parallel, and run true from the front to the back of the brace, and still have vertical runout, which is undesireable. The grain gan be slanted from the top to the bottom. Some luthiers call this "invisible runout" because you cant' see it by just looking, you have to split a peice and see how it runs, and saw parallel to the split. Otherwise the brace or top is weakened to the degree of severity of the runout.
The way you can see the runout in a top is, when looking at the top of the guitar at an angle, one side is noticeably darker than the other. This is because the endgrain of the invisible runout is reflecting the light darker. Look at the guitar from the opposite angle, and the side that was dark will be light and vice versa, as the endgrain reverses.

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Old growth, shmold growth!

My point exactaly. Both pictures are from the same brace. Nice veritcal end grain, but not something I would want to use.

Actually, Alan, those photos do not illustrate my point. You can see the "grain" (annular ring) lines running out on that stick. They run out on the tangential surface. It's the runout on the radial surface that you can't see (not easily at least), and that you split on a radial surface to avoid.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

One might get wood this poorly cut, depending on where it came from. I agree it's unlikely if purchasing wood from trusted suppliers that knows what they are doing. However, it's very possible that someone may cut wood that looks like that this if simply sawing to get vertical end grain and not looking for the run out....which is why I thought the pictures might be useful in showing why good vertical end grain doesn't necessarily indicate the wood will make a good brace.

In any case, I do split my brace wood to avoid run out. Doesn't take much time and makes for better braces.

Sorry...you're right. I read the post during a break from cleaning out the shop and found this piece, so thouht it might be helpful to see the pictures.

Yes, that would be the side to show, but couldn't get a good picture of it. Thought the obvious defect from the top would make the point about vertical grain not being the only thing to look at.

I was going to split another piece to show how it splits (the piece has a lot of run out), but couldn't find my brick chisel that I use to split the wood. I'm trying to clean up the shop now, so hope I find it in the process.

Another picture of the same brace. I couldn't get a picture showing what I wanted on the side when I did the other pictures, then it dawned on me to show it this way.

Not a luthier here, but I am interested enough to have been reading this forum for some time now (couple of years?), and I felt the need to say that the first picture, illustrating the grain run-out caused me some distress...

Sawing wood is a three dimensional adventure. Yes, you can take a board out of a log, and you can quarter saw it perfectly, and the end of the board will show perfectly vertical grain lines, but..... when you go to rip your bracing strips out of that quarter-sawn board, you need to be sure that you're cutting parallel to the bark, or run-out is almost a certainty. I won't offer an opinion on splitting to reduce run-out other than to say that snowshoes were traditionally made by splitting Ash wood to get straight grain frame pieces, but if sawing for straight grain is what you do, remember to cut 90' to the grain to make the board, then parallel to the bark to keep the grain straight during the rip.

cheers

John

Note : no matter how careful you are with grain orientation, some boards are just too wild in the grain to get anything straight ....they are also some of the nicest ones....
Note #2 : While I am not a luthier, I have been a sawyer for some time now - running a 25hp 30"x20' portable band mill, doing custom cutting.

That's the "invisible runout" that I was talking about. Bad in soundboards, worse in braces.

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Old growth, shmold growth!

Not talking about those lines, I'm talking about the ones you can't see that run from the front to the back or vice versa, at and angle transversing the top and bottom planes.
You can't see them 'cuz they're invisible.

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Old growth, shmold growth!