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Old 08-05-2020, 06:21 PM
fregly fregly is offline
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Default How to tell tonewood is well quartersawn?

I mean back and side wood, some call the top tonewood. How do you tell in a completed guitar when you cannot see endgrain. I know it does not matter for all tonewood but for some it is superior. Can you know if the grain is narrow and symetrical? is cross grain a sign, as with spruce?
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Old 08-05-2020, 07:00 PM
charles Tauber charles Tauber is offline
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In some species of wood, the medullary rays are visible if the wood is quarter sawn. White oak, for example, has huge medullary rays.



Maple has smaller, but still visible medullary rays:



mahogany as well:



In many other woods, the medullary rays are not obvious to the naked eye when quarter sawn.

The presence of a "cathedral" or "V" grain is a sure sign the wood is slab cut (flat/plain sawn):



Both quarter sawn and rift sawn wood have straight grain. Often a board will change across its width from quartered to rift or to slab/flat. Here is one example of that, rift or quartered in the middle changing to slab towards the edges:

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Old 08-05-2020, 07:06 PM
fregly fregly is offline
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Wonderful! Thankyou Charles.
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Old 08-05-2020, 07:51 PM
John Arnold John Arnold is offline
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Please ignore the rift sawn diagrams that are prolific on the internet. The end views actually depict radial sawing, where the growth rings are vertical. True rift sawn never has vertical grain. It is usually between 45 and 75 degrees.
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Old 08-05-2020, 08:01 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by John Arnold View Post
Please ignore the rift sawn diagrams that are prolific on the internet. The end views actually depict radial sawing, where the growth rings are vertical. True rift sawn never has vertical grain. It is usually between 45 and 75 degrees.
Good point.

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Old 08-06-2020, 04:13 AM
fregly fregly is offline
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https://www.musicstore.com/en_OE/EUR...GIT0049950-000

So this guitar looks rift sawn at center, and flat at sides. Not optimal for oak.
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Old 08-06-2020, 07:42 AM
John Arnold John Arnold is offline
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Rift center and slab on the outer edge is common on two-piece backs today, because of the smaller size of the trees. Offsetting the heart to the outer edge is practiced because it is more stable, and is generally considered more attractive. The heart (the peak of the cathedral) is where the wood is most likely to crack, and placing it outside the waist wil minimize that.
The appearance of cross silk indicates perfectly vertical grain, but distinguishing 45 degree grain from 75 degree grain is going to be difficult without seeing the end grain. IMHO, once you leave perfectly vertical grain, the functional difference in 45 versus 75 in hardwoods is marginal. In fact, 45 degree grain is the least likely to crack.
Normally, 75 degrees is where the distinction is made between rift and quarter, even though the narrowest boards produced from the quartersawing process will be close to 45. What it does produce is vertical grain on the widest boards, which coincidently will be the most useful for guitars.
A premium is placed on vertical grain for softwood tops, with good reason. Softwoods (AKA conifers like spruce, cedar, etc.) have rectangular cells that will distort to parallelograms if the grain is not vertically aligned. That is why a spruce top that is only a few degrees off-quarter will be markedly less stiff, particularly across the grain. But hardwoods behave differently, because the cells are roughly circular. So the stiffness does not change much with the grain orientation. As a result, the sound does not change with different cuts of hardwood, though the stability is affected. In other words, choose quartered hardwoods for their superior stability and appearance (dead quartered if cross silking is the desired look). But for sound, use your ears.
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