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I think this has been posed before, but I couldn't find it in the search...
When taking a look at tonewoods for back and sides, how important is it to get the quartersawn? I seem to recall some pretty spectacular guitars that looked flatsawn.
Do certain woods matter more than others?
How stable is flatsawn?
I've seen some pretty nice specimens at my local wood store and was just wondering how feasable it would be to resaw a piece for a top and back set if it was not quartersawn.
Thanks
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Tops- quartersawed only
Backs- either one works fine
sides- quarter is better, but sometimes flat will work if you are careful.

Al

    Actually flatsawn on most woods will eventually split. The movement is across the grain as with quartered the wood is more stable. You have to watch for runout , quarter and stifness.
john hall

A big factor is the kind of wood. If a species of wood has a tangential shrinkage of 5% or less, it is as good from a shrinkage standpoint as many species are quartersawn. Lots of wood properties info on the web, or check out Hoadly, or get a copy of the Woods Of The World software, or.....

So the bottom line is not flatsawn vs quartersawn, but rather, the properties of the wood in question.

Grant

I'm pretty much with Al on the wood for the soundboard: for stability, stiffness, aesthetics (good bookmatch), I would not stray far from 90° quartersawn wood for a soundboard.

For backs and sides, you may want to consult a chart of radial and tangential shrinkage values, to help you make a decision with each wood specie as to whether it will likely fail over time (due to natural expansion and contraction.) These charts are all over the web, often under the heading of "wood characteristics" or "wood drying properties."

The percentage number in the chart listed as "Radial" is the percentage of movement (from one point to another, like "green" to "6%MC") for quartersawn wood. I am pretty sure that without exception, wood always moves less (sometimes considerably less) when quartersawn than when flatsawn.

The percentage number listed as "Tangential" refers to flatsawn wood. Note how much higher the percentage of movement is for flatsawn wood, sometimes more than double!

(Charts list these ideal figures, and though you can buy some strictly quartersawn wood, the flatsawn wood is usually flatsawn at some point, and rift at other points. So, you will have to look at the end grain of each piece of wood, determine what amount of the board is truly quartersawn (radial), what amount is flatsawn (tangential), and what amount is riftsawn (interpolate between the radial and tangential figures.)

Now that you see how to read the chart for a particular board of a particular species, I think it helps to have something to compare it to. I have seen a number of Quilted Maple guitars, made by pro luthiers, that evidently live a long life "in service" (with all of the humidity swings of the seasons.) Since Quilted Bigleaf Maple is typically as flatsawn as possible (to show off that poufy pillow figure), I use that as a point of reference. So, if I look up a wood species, and see that the percentage of tangential movement is greater than Bigleaf Maple, I would be afraid to use it flatsawn. If it is about the same as Bigleaf Maple (or less), I would not be afraid to use it.

Since we are talking about a change of width of the board, over a spectrum of humidity conditions, the narrower the instrument, the less you need to worry about wood movement. And, of course the opposite is true as well.

A couple of other points would be that many luthiers who have bent flatsawn wood into sides report a much higher rate of rippling - even when using silicone blankets on solid forms. I think most experienced luthiers agree that quartersawn wood bends with a lot less surprises.

Also, it is easy to get a beautiful bookmatch (at the back seam, and the butt of the sides) with perfectly quartersawn wood. You could even cut 3 slices from a well-quartered board and toss the middle one out, and still get a good bookmatch with the other two. But with flatsawn wood, you will want to cut with a very thin kerf and virtually no blade wandering, and then sand as lightly as possible just to get a reasonable bookmatch.

Do I get a can of lard or a hot air balloon for being long-winded? Hope this was helpful to someone.

Dennis

{edit: Grant, you type faster than me!}DennisLeahy38811.0484027778

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Bravo, Dennis!

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Wow! Thanks. Some excellent things to think about...especially with the bookmatching aspect of it.
Thanks, all. Especially Dennis.
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Aside from the bookmatching issue, there is also just the distinctly different look of flatsawn versus quartersawn. It's completely subjective, of course, but if you haven't really spent some time looking at guitars with flatsawn backs and asking yourself whether you like that look, that would be a good exercise.

Speaking for myself, I would rarely go with flatsawn even if I knew the wood I was working with wouldn't be likely to present stability problems.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

I also prefer quartered for stability reasons, but some types of figure, like birds eye maple, only show up when the wood is flat sawn. Other types of wood are hard to find in big enough quartered pieces, so you settle for flat sawn, think BRW. I have made both maple and mahogany guitars with flat sawn backs and sides, no more problems than usual, they are all still going strong, 6 Norwegian heating season after! I agree with Grant, it is "not flatsawn vs quartersawn, but rather, the properties of the wood in question".

One of my professors when I went to architecture school used to say: "If I have to chose between beautiful and practical, I always chose beautiful!". His houses were always highly practical by the way, but he had a good point, and it certainly makes life more interesting.

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Rian Gitar og Mandolin

Guitars need to be very efficient in carring a load. Wood must be exploited for the most strength with the least amount of weight.
Beauty and variation of grain is most accomplished by cutting off quarter . Stability ( shrinkage ) cupping and humidity influence are all design factors. So with the idea of design you have to look at what problems are you designing into the instrument.
   Waterfall graining is a result of flatsawn most of the time. If you understand that you run more risk of cracking using flat and that humidity influences will cause seasonal movement and you design for that you may be okay but eventually the wood will win and it probably will crack. I admit some flatsawn wood is very eye appealing but I won't use it. Pretty wood isn't allways strong wood.
   Nothing is more dissapointing then having to rebuild a commision because you selected material that wasn't stable enough to carry the load.
john hall
   

There is obviously a lot of personal prejudice in this area, which is fine. One must do what one is comfortable with. There is also, not meaning to step on any toes, a lot of opinion based on a shortage of knowledge. So, again I stress, get to know your wood. That is what made the old masters good, they understood the wood. Use it right and treat it right.

Flat sawn vs quartersawn is a gross oversimplification. It takes a huge tree to get totally perfectly flatsawn wood the width of half of a guitar back, much bigger than it takes to get a perfectly quartersawn piece the same width. So backs cut from trees that are too small to cut fully quartersawn backs are never very flatsawn, except for an inch or two of width, at most. Wood sold as quartersawn can be close to 45 degrees off (yes, I know that this is often called rift sawn, but the term is rarely used in the lumber trade except for speciality cuts such as rift sawn oak, which is showcasing the grain pattern more than anything).

Perfectly flatsawn mahogany (which can be found) is as stable as quartersawn rosewood, and more stable than quartersawn maple. Some species, noteably wenge and padauk, are prone to splitting along the growth rings (ring shake), and may actually be a bit less prone to cracking if cut a bit off quarter. and, so on and so on..... So again I say, get to know and understand wood and then don't let "is it quartersawn?" be the first question you ask.

Grant

Very well said, Grant.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

There are some excellent answers here to a good question. I am impressed.

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Joe Beaver
Maker of Sawdust

"It takes a huge tree to get totally perfectly flatsawn wood the width of
half
of a guitar back, much bigger than it takes to get a perfectly quartersawn
piece the same width."

It's exactly the opposite....

One can mill very nice well-milled slab-cut 9" wide boards from a
relatively
small tree that would never yield quartersawn material of the same
widths...

BTW, slab-sawn spruce tops have been used in the past, but is sure
isn't
something I'd recommend....

I remember seeing a very cool violin in the Ashmolean Museum in Oxford,
England, that was built from heavily-bearclawed slab-cut spruce.
The resulting top was just too cool, with the claw marks all over that
top just like you'd see in the cambium of a nicely figured bearclaw tree...
Cool look...

Here's a pic of a slab-sawn Curly Sitka top resawn from a billet that only
had a few inches of width, so it got slab-sawn just for grins.....
The bi-coloring is sun staining and not in the wood....

Interesting look, surprisingly stiff, but not something I'd recommend
using...   

spruce38811.5709259259

[QUOTE=Grant Goltz]
Flat sawn vs quartersawn is a gross oversimplification. It takes a huge tree to get totally perfectly flatsawn wood the width of half of a guitar back, much bigger than it takes to get a perfectly quartersawn piece the same width. So backs cut from trees that are too small to cut fully quartersawn backs are never very flatsawn, except for an inch or two of width, at most.

Perfectly flatsawn mahogany (which can be found) is as stable as quartersawn rosewood, and more stable than quartersawn maple.

Some species, noteably wenge and padauk, are prone to splitting along the growth rings (ring shake), and may actually be a bit less prone to cracking if cut a bit off quarter. and, so on and so on..... So again I say, get to know and understand wood and then don't let "is it quartersawn?" be the first question you ask.

Grant[/QUOTE]

It's unrealistic to expect "flatsawn" wood to be perfectly "flatsawn" with growth lines perfectly parrallel to the surface and hold this as a "standard". We all understand and accept the way sawn lumber is converted from stems. Flatswn lumber (by grading standards) is way more available than equivalent widths of quartersawn. That's why quartersawn lumber is narrower in width and more expensive.

Perfectly flatsawn mahogany (which can be found) is as stable as quartersawn rosewood, and more stable than quartersawn maple.

I think a more accurate statement would be, "Perfectly flatsawn mahogany can be as stable as quartersawn roseewood and can be more stable than quartersawn maple." We select acoustic instrument wood by species for common traits and characteristics, but we select individual pieces of wood for specific characteristics. Not all flatsawn mahogany is stable nor is all quartersawn maple not stable.

Some species, noteably wenge and padauk, are prone to splitting along the growth rings (ring shake),

Ring shake is a defect found in tree stems where the growth rings separate while the tree is living. (Not to be confused with heart shake.) Many causes for this defect. Some species (wenge and ziricote for example) are more brittle and prone to cracking when quartersawn, but it is not due to ring shake.

Giving the different expansion rates of flatsawn and quartersawn woods in the same species, one should think twice about mixing grain directions in the same instrument. Quartersawn sides and flatsawn backs will expand/contract at different rates (so will mixed species)

Bottom line, it's a choice a builder makes when designing a project. An acoustic box is a frame of .80-.100 thickness, held together by a thin, heat sensitive glue line with strings under tension taking the box to near destruction stress and holding it there. Why settle for anything but the best materials that stack the odds in favor of success?

I agree with Grant. The largest board you can cut from a tree is straight through the center. It will be quartersawn. Aperfectly flatsawn board of any size would require a very large tree. I'm not a woodsman but that seems right to me.

Ron

_________________
OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

As has been said, you have to know your wood. Still, there are a few useful generalizations that can be made.

_Dead_ flat sawn wood can be quite stable, but has to be cut from really big trees or made up from narrow pieces. The big stability problems I've had seem to come from changes in the grain direction: quartered in the center and flat in the wings can be a very bad cut, particularly with some woods, like BRW.

Skew cut, with the ring lines at 45 degrees to the surface, is the most resistant to splitting, but has the lowest cross grain stiffness. I like to use skew cut for end blocks and bridge pads, and also for harp soundboards, where the grain lines run across the top. Quartered padauk has wonderful cross grain stiffness, but can only be flexed a little bit before it cracks. Ditto redwood, in my experience.

It seems as though the medullary ray lines weaken the bond between cells a bit, and that might account for some of the splitting problems with flat cut wood. I can't recall ever seeing a bird guitar back more than about 25 years old that didn't have splits meandering all over the place. So much fun to fix....

[QUOTE=old man]   The largest board you can cut from a tree is straight through the center. It will be quartersawn.   I'm not a woodsman but that seems right to me.

Ron[/QUOTE]

That would be incorrect. Pith and juvenile wood MUST be removed. You'll have two smaller quartersawn boards either side of the pith and juvenile wood. And if it's an exotic (rosewoods, wenge etc) the sap must be removed also further reducing the usable width.

[QUOTE=Arnt] One of my professors when I went to architecture school used to say: "If I have to chose between beautiful and practical, I always chose beautiful!". His houses were always highly practical by the way...[/QUOTE]
Yes, but did he mean practical, as in "cheap & expedient", or as in "elegant & functional"? I bet it was the former. Functional simplicity can be extremely beautiful. Flashy gaudiness can be quite ugly.

Looks like there are many opinions on this subject and many different interpretations of terms.

When I say "perfectly flatsawn" I mean tangential grain from edge to edge. That takes a big tree. I have seen it in Honduran mahogany. "Slabsawing" is a process, not a product. From small logs it produces a mix of near vertical and tangential grain, with a lot somewhere in between. A cut totally through the center of a log produces almost all vertical grain, and yes, it must be made into two boards to get rid of the center. I thought that was obvious    So far as sapwood goes, it is mostly a matter of personal preference to use it or not. In most species it is perfectly OK. I know that not everyone would agree with that, but that is based on opinion, not fact.

A back that starts out vertical grain at the center and runs out to near tangential grain at the outer edge is not a "worst case scenario". The vertical grain portion will still have the shrinkage of vertical grain wood and the outer edge will have a bit higher shrinkage. But since that represents a very small percentage of the total width, it should rarely be a problem.

Quartersawn sides with near flatsawn backs is never a stability problem, since the two have no influence constructionally on each other. If that were a problem we had better start worring about what kind of tops we put with our sides

Grant

Just a point of interest. A perfectly quartersawed neck blank 3" X 4" is actually perfectly flatsawed then turned 90 degrees.

Al

[QUOTE=A Peebels] Just a point of interest. A perfectly quartersawed neck blank 3" X 4" is actually perfectly flatsawed then turned 90 degrees.

Al[/QUOTE]

Yep! That's what I say too. One man's quartersawn is anothers flatsawn. It all depends on your perspective. Or as we say, how it's lying....

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Joe Beaver
Maker of Sawdust

"Yep! That's what I say too. One man's quartersawn is anothers
flatsawn"

Yep...
Just ask a violin maker about how neckblocks should be sawn....

"When I say "perfectly flatsawn" I mean tangential grain from edge to
edge."

Oh, OK...

Well, I guess I'm more concerned with whether or not it's properly
slab-sawn...

In other words, do the resulting grain lines form "puddles" or
"horseshoes"...?

That's the key to whether or not you're going to have problems down
the line due to poor milling of a given log....

I agree with that, but, to get a perfectly flat sawn board of some size you would have to take a cut parallel to the sap wood, and it would have to be a huge tree. Seems to me.

Ron

_________________
OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

[QUOTE=CarltonM] [QUOTE=Arnt] One of my professors when I went to architecture school used to say: "If I have to chose between beautiful and practical, I always chose beautiful!". His houses were always highly practical by the way...[/QUOTE]
Yes, but did he mean practical, as in "cheap & expedient", or as in "elegant & functional"? I bet it was the former. Functional simplicity can be extremely beautiful. Flashy gaudiness can be quite ugly.[/QUOTE]

Carlton, I think he was joking a bit; I guess should explain the context...

As you say, functional simplicity can be quite beautiful, I agree with this with all my heart. But my professor was actually quoting HIS professor, Fredrik Konow Lund, who was an architect caught between the neoclassicism of the 1920's and the new modern movement where function was EVERYTHING and "form follows function" was the new slogan. I guess his comment was a tongue in cheek comment directed towards some of the more militant members of the new movement. Konow Lund's architecture was a wonderful mix of old and new in very a distinctive, personal style, but as I said both quite functional and beautiful. There is a book about him titled "Arkitekten som moret seg" (the architect who enjoyed himself), I guess that is a pretty good description of the guy. He did not want to follow any set of rules too rigidly, and I guess that was the essence of this message, and perhaps the main thing we can learn form him.

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Rian Gitar og Mandolin