This is designed to be a thread to help educate sawmillers and other timberworkers how to harvest and prepare wood for use as tonewood in Acoustic musical instruments.
(Makers of solid body instruments such as electric guitars and basses can afford to be less precise in their requirements because they are dealing with thicker pieces of timber and can laminate timbers for strength and looks. Feel free to disagree though)
There are a lot of people cutting wood, supposedly for use in acoustic instruments because of the value-add, but unless it is done right, the wood can easily end up as expensive firewood. People who know how to properly cut, dry, store and prepare wood for acoustic instruments are in demand and will earn repeat custom.
Acoustic instrument makers are (and need to be, because they are dealing with very THIN wood) quite exacting.
Acoustic instrument makers generally value wood with the following properties:
quartersawn - gives strength, stability and acoustic springyness, and often accentuates th figure in the wood
clear - no knots and twists
tight grain - close spaced grain
no runout - grain runs straight, doesn't split
high figure - highly figured backs and sides often command a higher price
bookmatch - timber than is resawn and opened out flat provides a symmetrical look that is favoured by many makers
dry - tonewood needs to be carefully stacked and air-dried
If an instrument is made from timber that has a high water content, it will shrink as it dries out, and the instrument will crack and fall apart.
Wood for acoustic musical instruments is almost ALWAYS quartersawn, and traditionally cut from split wedges to minimise runout. This is for strength along the grain, and also the flame is usually accentuated this way. If there is any runout, you risk splitting the wood during the rib bending process. Also, if there is runout, a top can crack in unpredictable ways.
Instrument tops and soundboards are usually made from pine species, spruce and cedars; luthiers look for tight, straight, vertical grain. The wood needs to be light and stiff, and spruce is the most popular. But spruce doesn't grow in Australia. Some alternative candidates available in Australia are:
King Billy pine
Bunya Pine
Hoop pine
Australian Cedar
Celerytop Pine
and there are probably others
Backs and sides are from harder woods traditionally, chosen for figure, stability and acoustic properties. Maple, Mahogany, Rosewood are traditional. Blackwood, Qld Maple, Eucalyptus, there are plenty of local candidates (see the http://www.mcguitars.com.au/forum/viewforum.php?f=9 aussie tonewoods forum).
Now, I am not an authority on cutting or preparing timber from trees or fallen logs. I've written about what I and I think other luthiers are generally looking for in timber. I can't speak for everyone though, so I invite you to chime in here with your experience and advice, dimensions, etc so that if someone wants to provide us acoustic timber, they've got somewhere to start from, and we makers have a good chance of receiving good timber properly cut.
Tonewood 101 - So you want to cut a tree into tonewood?
Hey matthew, sorry mate my ears are burning. im glad you posted because some of you are aware of my queensland maple which i have found and i am going to process soon within a month or two. Ive had a heap of experience in resawing and in particular drying valuable quarter sawn timber and normal backsawn timber and the only real worry is really in the backsawn timbers stability and general movement when drying, particularly when cut green. Ive seen some green backsawn timber of beautiful rose mahogany and red cedar do some things to warrant it unusable due to poor drying and milling. In my experience well quarter sawn timber that is stacked to dry properly and 'end sealed' is very well behaved in terms of movement both tangentially and more importantly radially.
There is an interesting read in the following link which has real merit within our native timber to a degree but our humidity range is much lower than the UK figures that are being quoted. I picked up some useful info about spruce and other non native timbers through here.
http://www.chilternsaonb.org/downloads/ ... Timber.pdf
Anyway i just wanted to ease the concern that there may be some loose cannons out there trying to make money where their knowledge dosn't really have the experience to warrant offloading quality. Hope this helps the worry. cheers Andrew
There is an interesting read in the following link which has real merit within our native timber to a degree but our humidity range is much lower than the UK figures that are being quoted. I picked up some useful info about spruce and other non native timbers through here.
http://www.chilternsaonb.org/downloads/ ... Timber.pdf
Anyway i just wanted to ease the concern that there may be some loose cannons out there trying to make money where their knowledge dosn't really have the experience to warrant offloading quality. Hope this helps the worry. cheers Andrew
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matthew
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Hey, my post wasn't directed at you, or anyone else in particular 
But I have had contact with a few people lately with access to what culd be nice timber who are seeking to provide to luthiers and I thought it would be a good idea to get a bit of discussion going so you guys can learn what we do and what we need, and find out the best way to turn that lumber into tonewood.
For example I have a mate here in Sydney who is a tree surgeon and he occasionally finds interesting timber in garden trees. The stuff I wrote above, is the sort of thing I tell him, so he can keep an eye out for me. Nothing yet though
I don't know how many times I've given out "bass" dimensions to people. There must be specs that guitar luthiers use, too.
You're right that backsawn isn't so stable, and that's the reason we don't usually use it, at the thicknesses we use it really doesn't hold its shape as well, and shrinks and swells unacceptably.
But I have had contact with a few people lately with access to what culd be nice timber who are seeking to provide to luthiers and I thought it would be a good idea to get a bit of discussion going so you guys can learn what we do and what we need, and find out the best way to turn that lumber into tonewood.
For example I have a mate here in Sydney who is a tree surgeon and he occasionally finds interesting timber in garden trees. The stuff I wrote above, is the sort of thing I tell him, so he can keep an eye out for me. Nothing yet though
I don't know how many times I've given out "bass" dimensions to people. There must be specs that guitar luthiers use, too.
You're right that backsawn isn't so stable, and that's the reason we don't usually use it, at the thicknesses we use it really doesn't hold its shape as well, and shrinks and swells unacceptably.
its amazing the lack of emphasis put on quarter sawn timber within building of fine furniture and instrument construction. In the paper ive linked to above, it states that a board of 225mm wide will shrink up to 5mm radially and 10mm tangentially. This is within the drying process, however when backsawn and quarter sawn pieces are compared, tragically (in instruments), if the guitar or furniture experiences different EMC (equilibrium Moisture Contents) or % change in humidity over a long period, it all very sadly goes horribly pearshaped and impossible to fix the damage that has been done by massive shrinking stress.
If anyone has ever had floorboards that are supposed to be kiln dried, laid in their house(mostly backsawn or off quarter), and have had access to a dehumidifyer, like i did, you will notice it takes two months to wreck some of the boards to the point of irreversable damage. The boards that were quarter sawn were identified easy because they didnt budge.
It (EMC or moisture content) should really be considered before we go spraying the finish on our pride and joy.
If anyone has ever had floorboards that are supposed to be kiln dried, laid in their house(mostly backsawn or off quarter), and have had access to a dehumidifyer, like i did, you will notice it takes two months to wreck some of the boards to the point of irreversable damage. The boards that were quarter sawn were identified easy because they didnt budge.
It (EMC or moisture content) should really be considered before we go spraying the finish on our pride and joy.
Thanks Matthew and Xray. Its a subject that interests me too. There is quite a bit of info available on line about do-it-yourself solar driers and resawing, but not a lot about dehumidifier driers, and unfortunately the two URLs listed in that pdf download are no longer available.
This page includes some basic info about tree felling according to the moon phase (see also http://www.best-eurospruce.com/4.html ), and a bit of basic but useful info about drying with dehumidifier.
http://www.unique-rustic-creations.com/ ... e-wood.htm
BTW, the article advocates using an electric heater in addition to a dehumidifier. That would not be a good idea in Australia except perhaps on cold winter days in Tassy or Vic, for example. Small dehumidifier units such as the one I have in my workshop warm up the air as well as lowering the humidity. Using it specifically to gently dry stickered quarter sawn boards, I would use additional fans to circulate air through the stack. Please note that I have not tried this and won't be until we move back to Oz in a couple of years.
I'd appreciate advice from anyone who has successfully used a solar or dehumidifier drier.
This page includes some basic info about tree felling according to the moon phase (see also http://www.best-eurospruce.com/4.html ), and a bit of basic but useful info about drying with dehumidifier.
http://www.unique-rustic-creations.com/ ... e-wood.htm
BTW, the article advocates using an electric heater in addition to a dehumidifier. That would not be a good idea in Australia except perhaps on cold winter days in Tassy or Vic, for example. Small dehumidifier units such as the one I have in my workshop warm up the air as well as lowering the humidity. Using it specifically to gently dry stickered quarter sawn boards, I would use additional fans to circulate air through the stack. Please note that I have not tried this and won't be until we move back to Oz in a couple of years.
I'd appreciate advice from anyone who has successfully used a solar or dehumidifier drier.
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matthew
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Recently I did a steam-bending workshop with a modern-day pioneer of steam bending Michael Fortune, who does a lot of work steam bending everything from chair legs to telegraph poles (I kid you not).
One of the things he said is that for any type of heat bending, naturally air dried wood is significantly easier to bend than artificially dried wood. He said the high temperatures in kiln drying (don't know about solar kilns) do have a permanent effect on setting the lignin bonds, resulting in a harder wood but much more difficult to bend. Air dried wood is also easier to carve.
You would think that this lignin-setting effect would translate to stiffer (less springy) wood in general. This might have an effect on tone, and judging by the fact that luthiers tend to prefer air-dried wood any day, the effect would seem to be an adverse one.
One of the things he said is that for any type of heat bending, naturally air dried wood is significantly easier to bend than artificially dried wood. He said the high temperatures in kiln drying (don't know about solar kilns) do have a permanent effect on setting the lignin bonds, resulting in a harder wood but much more difficult to bend. Air dried wood is also easier to carve.
You would think that this lignin-setting effect would translate to stiffer (less springy) wood in general. This might have an effect on tone, and judging by the fact that luthiers tend to prefer air-dried wood any day, the effect would seem to be an adverse one.
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Dennis Leahy
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Yeah, I've seen diagrams like that before. In the US, there are standards defined by the American Institute of Architects that are supposed to define just how far off of 90° vertical grain the lumber can be and still be called "quartersawn."
In that diagram J Jones supplied, the flat sawn wood is the most typical way that lumber is cut in American mills, and it is sometimes referred to as "through and through" and would continue with parallel cuts through the entire log. In the top half of the los labeled "Sawn Flat", certainly the first two or three boards are flatsawn, but then (to me) it gets down to rift sawn wood in the next few boards, and that final board in the stack labeled as "sawn flat" is perfectly quartersawn.
I have a feeling that the terms "rift" and "quartersawn" were either labeled incorrectly in some old reference, and newer references simply copied the mistake and carried it forward, or else the terms flip-flopped in their meaning at some point.
A very common hardwood lumber in the US is Red Oak, which has strong medullary rays if the grain orientation is very close to 90° vertical. I have dealt with architects on large commercial woodworking projects that were very clear to specify "rift sawn" wood when they wanted rather boring and featureless grain, and specifically did not want the medullary rays to appear (as they would, if the wood was well quartersawn.)
So I agree with J Jones that simply saying a word that you think is universal may result in something different than what you really want. To my eyes, in that diagram above, the entire lower left quadrant is quartersawn; the center three boards in the lower right quadrant are quartersawn, and the bottom piece in the upper stack is quartersawn.
Dennis
In that diagram J Jones supplied, the flat sawn wood is the most typical way that lumber is cut in American mills, and it is sometimes referred to as "through and through" and would continue with parallel cuts through the entire log. In the top half of the los labeled "Sawn Flat", certainly the first two or three boards are flatsawn, but then (to me) it gets down to rift sawn wood in the next few boards, and that final board in the stack labeled as "sawn flat" is perfectly quartersawn.
I have a feeling that the terms "rift" and "quartersawn" were either labeled incorrectly in some old reference, and newer references simply copied the mistake and carried it forward, or else the terms flip-flopped in their meaning at some point.
A very common hardwood lumber in the US is Red Oak, which has strong medullary rays if the grain orientation is very close to 90° vertical. I have dealt with architects on large commercial woodworking projects that were very clear to specify "rift sawn" wood when they wanted rather boring and featureless grain, and specifically did not want the medullary rays to appear (as they would, if the wood was well quartersawn.)
So I agree with J Jones that simply saying a word that you think is universal may result in something different than what you really want. To my eyes, in that diagram above, the entire lower left quadrant is quartersawn; the center three boards in the lower right quadrant are quartersawn, and the bottom piece in the upper stack is quartersawn.
Dennis
Another damn Yank!
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vandenboom
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...yeah, that's nice, but I prefer this method 
http://www.youtube.com/watch?v=2bVAAx3m ... re=related
http://www.youtube.com/watch?v=2bVAAx3m ... re=related
Arnt Rian,
Norway
Norway
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Dennis Leahy
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Sawing necks
Getting back on track, I would like some advice on sawing necks. I have mastered the quatersawn, book matched back sets and sides and would now like to cut necks and heels out of pieces that are too narrow for anything else. I read on one forum that necks should be 80mm wide and 25mm thick. It also said they should be quatersawn along the 80mm side which is ambiguous.
Others recommend making necks by splitting the timber.
Any comments.
cheers
Stopper
Others recommend making necks by splitting the timber.
Any comments.
cheers
Stopper
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Rick Turner
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Rift sawn is generally considered to be with the grain lines running from about 30 degrees to about 60 degrees to the face of the board. The look of the wood tends to be fairly plain and even boring with no display of medullary rays, "ho-hum" figure, but not the evenness of vertical grain faces.
In lutherie, rift sawn is actually the best cut for guitar bridges. If you align the grain more or less parallel to the break angle of the strings, the bridge will resist splitting quite well, and still be reasonable dimensionally stable.
In lutherie, rift sawn is actually the best cut for guitar bridges. If you align the grain more or less parallel to the break angle of the strings, the bridge will resist splitting quite well, and still be reasonable dimensionally stable.
Rick Turner
Guitar Maker, Experimenter, Diviner
www.renaissanceguitars.com
www.d-tar.com
Guitar Maker, Experimenter, Diviner
www.renaissanceguitars.com
www.d-tar.com
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