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Here is a picture and an explanation of my troubles...



I cut an all new batch of the aged sitka today, along with a batch of adirondack on the left. Sitka appears pink or tan, while adirondack appears whitish-yellow. Notice that all the Sitka braces sheared with little flex, they just cracked and popped, and kept doing it until they were all gone. Notice the pile of adirondack, only two succumbed to the same treatment. Then look closely at all the breaks....

All the Sitka followed runout lines in the grain and so runout in my estimation is part of the problem with these. They also appear brittle, maybe something really related to the fact it's aged wood. So help me think it through, what's more important vitality or age which can induce great sound of a broken in guitar? For some reason, I go with vitality. Any good rap front or back of a guitar might cause this type of fracture.

Back to the Adirondack, now this wood is seasoned, purchased from a reliable supplier, and for the most part possesses resilience and vitality. I had one set of all you see crack and give up on my twisting, flexing torture test. So, my thoughts flittered back to William Cumpiano and Natelson's book. The haunting comment "I only use split braces".   Now, I'm a believer, not a doubter. William learned the lesson well, and taught it himself. Now for me, after today, "I only use split braces in my guitars".

Well, what do you think? The price of my guitars just went up. Bruce

Go look at the prices of some of Bill Cumpiano's guitars....they're lower than you might expect!
Good lesson.
I only use adirondack braces from split billets. That said, I will saw my braces off from the billet parallel to the split face. To me, that seems good enough. Maybe not. Maybe it is.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Ineresting test. Note that the effective thickness of the brace is 1/2 the unslotted thickness but the stiffness of brace is the full height except for were the slot is. Another interesting test you could do is to glue a spruce cap over the notch. This will restore the full height thickness over the notch.

Never the less, the 3" runout is pretty severe. You don't have to spit every brace. You can split each billet and saw the rest of the braces. So far I've bought my braces with a split face already in them so I haven't had to deal with runout or splitting.

The ideal brace has a grain line running from one end of the brace to to other.

Mike that is true. These adirondack came from a well known supplier, yet they have runout too. So, I just ordered some billets, no more sliced stuff for me. That's the point of this post. Runout doesn't just happen in brace stock it's cut in.

So, where you getting your split Adi billets from then? I'm going to split the blocks of Italian I got from rivolta (sawn), and contact them about the possibility of getting split billets, but we'll see..

Old bracewood will be brittle. it will also tend to be harder and stiffer. This takes many years to develop. I think almost any conifer exhibits this trait. I've done demo work on houses I've owned and those old 2X4's are hard as the dickens. Try and drive a nail into it and it splits. Those adi braces are still relatively young, I think if you give those Adi braces about 10yrs they will behave the same way. Got any of that old sitka left?

Yup, you want some? email me.

I told you there was too much runout. That is the result.

Nobody listens to me....

Minimize your runout, maximise the strength.

Mario. Telling some what runout is is one thing. Them experiencing it first hand is something else. Then by ignoring all warning signs, there comes the testing phase.

About all I proved was that old wood may not necessarily be good wood.

Second, even wood supplied by bonafide suppliers may not measure up.

Thirdly, testing hypothesis of stress and strength can be destructive and educational.

So, no, you can't learn it all by listening, sometimes you have to go ahead and try. Only to revisit comments from the elders of our craft and realize that split bracing is superior to sawn bracing.

Never stop making suggestions, because some folk listen faster and don't have mule-thick heads like me.

But you can run fast enough now to sell me any bracestock cut by someone else.... I'm a billet man now.

Sawn bracing can be fine; I'm an avide dumpster diver, always on the lookout for old woods. We don't have garbage pickup, so I head to the dump once a week with out garbage, and alwys run over to the wood section to go through the week's toss-outs before they burn it. I also chase down old home demolition/renovations.

The trick is to split a bit of it both ways to "read" the runout, then decide if it's usable. When you did so and showed us, I knew it was not going to make good top braces; still fine for backs! Backs braces aren't under a stressed load; they only need to hold the back's shape.

BTW, I always, always, destroy one brace, at least, from each billet, to "read" its strength, too. Some woods, even perfectly split both ways, will still have hairline fractures and such.

But you're right that we do have to see for ourselves, too. You did not waste your time with this; you have leanred more about spruce and what seperates good from bad, in one week than most will ever learn. Kudos!