Official Luthiers Forum!

I truly hope that "The End" doesn't mean that the discussion is being shut down. I still hope to learn something here. Perhaps what is to be learned is that it is, indeed a matter of semantics between sawyer and luthier. I thought that earlier in the thread but when I asked a question about the drawing of two billets and how if we pretended they were braces which one would be stronger, the answer surprised me. It was the opposite of my understanding and made me think that it was not a matter of semantics as I had originally thought. I think I see some feathers being ruffled in some corners; I'm not trying to stir up problems. I, like many of us, want to make sure I understand the terms AND concepts so we can get on with what is sure to be an interesting conversation about wood properties even if it doesn't have any bearing on how guitars are made.

I know see that I could have indeed made things worse with my question because I may not have asked it well enough (partially but not entirely my fault given the apprent disconnect in the way these terms are applied). A poorly asked question will give rise to just as much confusion when answered since different readers will understand the question and ensuing answer differently. For my part in that I apologize. Unfortunately, I cannot upload pics right now to illustrate my question. Let me try with text:

____|||____ this represents my understanding of the strongest orientation where the underlines (___) represent the plate and the pipe (||) represent the grain of the brace. Note that I am leaving the terms quartersawn and vertical grain out of the mix here even though until recently I would have use both interchangeably here.

This picture represents what I think of as the weaker orientation ____=____.

Thoughts?

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Please forgive the double post but the above was already too long to expect anyone to read. . .

One other tearm I am curious about is 'flower' grain. I have never heard it before and I don't know what it means. At first I thought it was an auto correct for lower but then I saw it again. Maybe it has no real relevance here but i'd still like to learn something.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Bryan, I will try 1 more time. There are no SEMANTICS to what I was trying to inform, except what others interjected who are most likely wonderful guitar builders, but are not lumbermen, sawyers or timber producers.
Quartersawn is a process, a sawing process. Vertical Grain is the descriptive name of a cut of product with the growth ring orientation at right angle to the wide face of a board/stick regardless of size. Whether 1 mm x 3mm or 1 foot x 3 feet or 1/4" x 9".
I learned the term Flower Grain from an old sawyer in Australia about 18 years ago. It is the face of a board that will run maybe between or split the growth rings. It would be the narrow edge of VG board or the wide face of a flat sawn board.

The VG cut soundboard has a totally different purpose then the brace so the application of energies and stresses are addressed differently. So whether someone wants to use the flatsawn brace or VG cut brace, it doesn't matter to me.
Grain slope is certainly more important that this orientation. But if ultimate strength is desired, the VG cut is supposed to be the one.
Take it or leave it.

Brent - Thanks for posting the diagram which makes clear your use of the term vertical grain from the perspective of a lumberman. From a guitar builder's perspective, only the brace on the right is described as VG. From your perspective, that's incorrect usage of the term, but in the instrument building world it is the convention and that's how it is. And that's why this thread has been so confusing.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

According to whom? What authority do you cite for this, Brent?

See, the thing is, the people who teach other people how to build guitars say that the diagram on the right, what you call flatsawn, is the proper way to orient the grain of braces that we glue to tops and backs in order to maximize strength for the lightest weight. If you say those people are wrong, then I would like to know the basis for that.

sigh...poor Brent...

sheesh...

Brent is using the term vertical grain correctly...the end

what's obviously confusing everyone here is the term 'quartersawn'...this is a sawyers term and means looking at a log from the end you would cut it into 4 pie shaped pieces of whatever length the log was...

quite wasteful, but does garner more vertical grain boards...

these days most all lumber is cut to maximize yield of usable product from a log and that means most of it is flatsawn...this is many times calculated out by a computer and a human 'approves' of the cuts and lets the machine cut it up...

take that darned brace on the right and rotate it 90*...it's now vertical...you don't need to understand E=mc^2 to figure that out...of course it's not high enough now for a brace, but point made.

if anybody doesn't have their terms correct it's us wood workers...quartersawn does NOT mean vertical grain (though a heck of a lot of people use that terminology)

http://www.simscal.com/6Bracing_SS_handout.pdf

then again, after just reading donparker's post I'm now confused...

yeah, that's the way braces are the strongest, with the grain lines running perpendicular the to plane of the item being braced...like a beam...grain running parallel to the direction the force is being applied...e.g. you have a 4x12 header for a door way, and the grain is supposed to being running vertically as you look at it from the end with 4" being horizontal and 12" being up and down

I'm going to venture a guess and say that when Brent has heard builders talk about VG with respect to braces, he's been interpreting their use of the term VG based on his lumberman's definition of VG. Brent - Please correct me if I'm wrong.

The lumber man's definition of VG is tied to the orientation of the grain with respect to the wide and short dimensions of the wood. That makes sense so that lumbermen can have a very specific set of terms that they can use to communicate unambiguously with each other. The guitar builder's definition of VG is not constrained by the grain orientation relative to the dimensions because it doesn't need to be, hence the use of VG to describe the standard grain orientation in braces which is perpendicular to the surface of the top or back regardless of the brace dimensions.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Semantics...

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George :-)

Mike, I left all terminology 100% out of my question. Yes, the terminology has been a source of confusion, so I deliberately stayed away from it. Brent says the diagram on the left is stronger. I want to know what authority exists for that, because most guitar makers use the grain orientation on the right. If we have been pooping wrong all these years, as Brent put it, then I want to know why he thinks that.

hence the edit of the post I made while you were making yours...

I'm just going to leave it at this:

the two times I have gotten woods from Brent were very enjoyable...he's easy to deal with and is all about giving the customer what they want...I highly recommend him as a direct supplier of spruce...e.g. he's the lumberman/sawyer/drier/salesman/packs the darned boxes and puts them in the mail...

No it's not. According to Brent's definition of VG: "Vertical Grain is the descriptive name of a cut of product with the growth ring orientation at right angle to the wide face of a board/stick regardless of size."

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Maybe he should put his url in his sig?

so this is the picture Brent posted a few posts back...

hmmmmm....I'm going to theorize here....said thinking is based upon what little I picked up from my father...aeronautical engineer...worked on the C-5a, C 141 projects back in the 60's...

in the case of a wing spar you need flex...you NEED the wing to be able to bend a bit as lift is applied to it from the airfoil...skipping wood, look at a B-52 on the ground...notice those wheels on poles at the end of the wings? gravity is pulling them down...in the air the wings are flexing up due to the lift they are receiving from the air flowing past the wings with an airfoil on them...get it?

this has NOTHING to do with ultimate strength...rather almost the opposite...if a wing under stress can't flex far enough it breaks...or yields to use the proper engineering term...so in the case of an airplane you want flexion as opposed to a stiff beam...a luthier would prefer by far the beam...keeping things in place...not allowing movement...especially on a top where the whole goal is to have as much stiffness with the smallest possible mass

I'll reiterate...strength in an airplanes wing is the ability to flex and not break...strength in the case of a guitar is the ability to resist the forces applied to it by the tension of the strings...two different concepts, 2 different grain orientations..

skipping what is a confusing set of terminology, the grain orientation on the right is the strongest when said word implies rigidity and keeping shape...whether it be a beam in a house spanning 40' or a brace (read beam) in a guitar...

hey...for all intensive purposes I just slapped him up the side of the head on the concept of strength...

I'll stand by my statements of his being a good supplier...along with RC Tonewoods and Colonial Tonewoods whom I have also had pleasurable dealings...any long timer here has read my negative (and removed) reviews of other suppliers...

Well, whatever ya'll want to call it is fine with me. I'm out of it anyway. Ideally a log is quartered and then the quarters rift sawn. That's the most wasteful, but gets the best quater sawn. Unfortunately, you get sections that are like the small chunk with the 45 degree grain and whom ever pointed out that it is kinda usable too. you just set the bandsaw at the right angle and you can quarter that chunk. It does give you a few braces but they get less and less tall. To those that OCD that the QS be absolutely VG, spilt it and watch it wind. I would never have spent the time to throw out all not perfectly VG cut bracing to use for kindling. In the complexity of instruments a few degrees mean nothing.
Yes, I suppose you could buy perfectly flat sawn wood and cut the braces the other way, but eh, it's all semantics. The sawyer has his name and we have ours. Some folks squabble about "rift" sawn...
I'm sure the sawyer here knows what he is doing, he's like my wife...she always comes from the other end. Good enough! Here's a smiley even
OK, next...

Hoo, boy, just when I thought it was all OK, you toss this in...



I don't know anyone that has done that for hundreds of years...(not that I am hundreds of years old, but some days it feels like it)...

Does anyone still split billets by hand for braces?

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wah
Wah-wah-wah-wah
Wah

I thought someone mentioned that earlier in the thread as a way of getting your reference surface to deal with run out?

I see your point Mike P. And now I have learned something regarding different strength types. I did know that the sitka would bend much more before failure then other woods, and it's weight to strength ratio was higher then other woods. I'll bet one or more of you analytical guys with measuring instruments could measure the 2 cuts. But based on what the engineering of the aircraft spar, it makes sense and sounds right. I absolutely stand by the terminology of the process and the cuts..
Now the end?
Or is someone able to actually measure 2 sticks of equal size, but different grain orientation from the same stick of stock.
Heck, I think I can round up the stuff for that, I just thought of some weights and aperatis[sp?] I have for a lubrication demonstration I used to do 30 years ago.... And Lord knows I have the board or 2.

But now, I'm gonna go set some gear for Halibut. a few hundred feet of 3/8" ground-line a number of circle hooks, via snap-on gear. with salmon heads for bait. And hopefully tomorrow morn some big flat-ones to bring into the boat.

I do. I split the billet with the grain first and then across the grain to determine the run out.

If the billet has little or no run out, the split across the grain will travel the length of the billet. If the billet you are splitting is VG as Brent defines it with the grain perpendicular to the wide side and it has run out, the split will exit the wide side of the billet before reaching the other end. The more run out there is, the sooner it exits the side and that limits the length of braces with no run out that can be made from that billet.

This is why I could see an advantage of using a flat sawn billet (by Brent's definition) to make long braces.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

When you take the flat-one off the grill it will be VG.

Thanks for starting this thread. It has been a blast. I have totally changed the way I cut braces, and then totally changed back to my old way of cutting braces, all without making any sawdust.

James

This from the USDA's Wood Handbook:

"Annual Ring Orientation
Stresses perpendicular to the fiber (grain) direction may be
at any angle from 0° (T direction) to 90° (R direction) to
the growth rings (Fig. 5–6). Perpendicular-to-grain properties
depend somewhat upon orientation of annual rings with
respect to the direction of stress. In some species,
there is no difference in 0° and 90° orientation properties.
Other species exhibit slightly higher shear parallel or tension
perpendicular-to-grain properties for the 0° orientation
than for the 90° orientation; the converse is true for about an
equal number of species."

Their "T direction" is vertical grain in the usual sense, meaning growth rings perpendicular to gluing surface. "R direction" means the the growth rings are parallel to the gluing surface. As you can see, some species exhibit greater stiffness in one direction while other species have greater stiffness in the opposite and in some species it makes no difference. It is a very simple test to determine the veracity of the claim that "R direction" is stiffer in Sitka spruce. Cut up braces of the same dimensions, one with "R" and one with "T" and measure the deflection. Then, you'd have to decide whether additional stiffness is a desirable property. One can easily see that a diving board that is too stiff won't launch the diver very well or a trampoline that is too non-compliant would not be much fun either.

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Stay with the happy people.
--Reynolds Large

Siminoff has looked at a lot of older instruments and writes that what we would call flat sawn can be stronger. We have seen various people over the years post data that indicates that either fully flat or fully vertical are typically strongest and falling off the vertical (in whatever direction) can lead to less strength. But at the end of the day we are only discussing maximizing the strength from a particular piece of wood. And that potential changes from board to board tree to tree. So, in my opinion, this is an almost irrelevant argument. You carve and otherwise shape your braces to get the stiffness you desire in your top. If you want your grain oriented in a particular direction send the vendor a picture of what you want and I am sure that you will get what you want. I only sold wood that was vertical grain, 3/4" by random widths so it was easy. Every once in a while I would cut some wood for a contra bass maker who preferred the wood in the other direction, we exchanged drawings and then I shipped what he wanted. Here is a thread on bracewood processing I did a couple of years ago.

http://luthiersforum.com/forum/viewtopic.php?f=10117&t=24665

Shane

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Canada

Having not cut a single brace can I be excused for never playing with the excess material and simply flexing it just 'cuz'? I mean who hasn't rummaged the wood pile looking for some scrap and testing the give just to see if you can use it for some weird axe use? I gotta believe some of you guys are doing this instinctively just testing the material? No? Some little off cut that just happens to be pretty close to square?

As this discussion applies to guitar making. To be clear more perfect to perpendicular the better -- this is what I was taught, what I teach and to this day know of no prominent maker or manufacturer that does otherwise -- I certainly could be wrong so lets start a list of those makers that orient braces like the one on the left.

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Ken Cierp

http://www.kennethmichaelguitars.com/