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#1
03-04-2021, 03:56 PM
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Cedar top wood question
I've had some cedar sitting in my shop for probably 15 years now. My wife and I used to own a cabin on a lake on Washington's Olympic Peninsula. Every spring we'd get a raft of logs that floated up to the shore from trees blown down by the winter winds. One year, my lake-neighbor/friend and I hauled several logs from the lake and had them cut into various shapes for different projects we had in mind. Some of it was knotted, but much of it was clear. Anyway, I'd kept it stored flat in my garage for years, then at some point resawed some clear slabs into pieces about 1/4" to 1/3" thick, 8-12" wide, 6' long. Wasn't sure what I was going to do with them, and certainly wasn't thinking guitar.
Earlier this week I was rummaging through the wood pile in my shop and wondered if any of that cedar might work as a guitar top. I've built some dulcimers years ago, but never a guitar and am now at a stage in life where I don't feel I have the decades left to become a skilled luthier. Since this cedar has some sentimental value (both the cabin and my friend have passed), I thought it would be nice to have a guitar built with this cedar as the top. So, at some point, I may seek out a luthier to have a guitar built. But right now I'd like to get a rough idea if that even makes sense, so I'm looking for advice. I cleaned up the ends of a few boards and wet them slightly to bring out the grain. As you can see in the photo, none of them are quarter sawn - the closest being the one on the top of the group of four. There are several other boards, not shown, because they aren't close to being quarter sawn. I measured the density to be 0.34 g/cm^3, and the moisture content is 7.6%. I don't know what species of cedar I have, since it just floated up to my cabin. But I know there are a lot of Port Orford cedars there. Is there anything else I can do that might tell me if there is hope for a decent guitar top? I suppose I could try to find a local luthier, but I'm not at all ready to have a guitar built yet. I just want to know if I should hang onto it before it disappears into other projects. Also, how far off quarter sawn does one typically go for a guitar top? 
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#2
03-04-2021, 04:14 PM
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Port Orford cedar has a very specific smell when worked: I call it dill pickle wood because it reminds me of the smell of dill pickles. It isn't a subtle smell.
Western red cedar also has a very specific smell as do some of the other aromatic cedars. Years ago, I used to cut my own guitar tops from western red cedar that I bought from a local lumberyard that specialized in cedar decking material. One board that I bought and re-sawed is, to this day, the best cedar guitar top material I've ever seen. Another board, purchased from the same lumberyard looks great but is scrap. It isn't stiff enough for me to use as guitar tops. One had a tap tone that rang for many seconds, the other a dull thud with no sustain. Both were perfectly quarter sawn, both looked nice. There are a variety of factors that determine whether a piece of wood is suitable for instrument use: being quarter sawn is only one of them. Stiffness can be very important, depending upon what a particular maker prefers, as well as runout. Although tap-testing it doesn't tell one a lot, taping it can give you some idea of how resonant it will be: there can be huge variation between one piece of wood and another, even of the same species. So if you tap-test a piece and it rings nicely and is very stiff for its thickness, even if a little off quarter sawn, it might still be a candidate. It isn't that difficult to find well-quartered cedar, but if you have some that is otherwise good and has sentimental value, if it has the other desirable qualities, it might be viable. The one at the top of your photo is probably close enough that it could be used, but far off enough that you won't see any medullary ray "silk" in the finished top. Last edited by charles Tauber; 03-05-2021 at 10:29 AM.
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#4
03-04-2021, 10:22 PM
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#5
03-04-2021, 10:23 PM
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#6
03-05-2021, 09:32 AM
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Many guitars have been built with not so perfectly quartered wood. Cedar is pretty stable stuff too. It's cool to have wood with a story behind it like that. I would build myself a guitar out of that stuff but perhaps not sell one like that unless the story is part of the sale. But having one built for you will be a nice heirloom piece and can certainly be a great sounding guitar too.
I build what I call my 'barn wood' guitars out of less then ideal wood. Oak and pine from an old barn, nail holes and all. But the instruments are rustic and appeal to certain people.
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#7
03-05-2021, 03:49 PM
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A lot depends on what shape of guitar you want. Well quartered wood has higher cross grain stiffness, and that drops off fast when you go even a little off quarter. Flat cut wood can actually be almost as stiff across the grain as well quartered, but when the grain lines are at 45 degrees to the surface ('skew' cut) you have the lowest cross stiffness you'd get from that tree.
A guitar that is wide in relaition to it's length, like a Jumbo or Dread, seems to work better with better quartered wood. Someting that's narrower, like a 12-fret 0 or 1, can be just fine with wood that's a bit off. Off quarter wood does have one other useful property; it's more resistant to spitting than quartered wood in some sense. It may not take any more force to split a skew cut top than a quartered one, but the skew cut top will put up with a lot more deformation or shrinkage before it splits. Flat cut wood, alas, tends to be more splitty. The other issue with flat cut is that wood shrinks differently with respect to the grain direction under humidity change. For a given moisture loss you get the least shrinkage along the grain, and most when the wood is flat cut ('tangential'), with the quartered shrinkage ('radial') being in between. If you cut something like a 2x4 near the middle of the tree (do they cut them from any other part these days?) there will be curvature to the ring lines on the end grain. As the wood shrinks the differential between the radial and tangential shrinkage will tend to make the ring lines on the end straighten out, so the piece cups. With well quartered wood the angle of the rings changes only slowly across the piece, and you see little, if any, cupping. Since the ring lines follow the surface of the trunk, flat cut wood that will show no curvature of the rings on the end would need to be cut from a tree of infinite radius. By definition, there can only be one tree like that in the universe, and it would take forever to cut it down. Most flat cut wood will cup across the span of a top.
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#8
03-05-2021, 07:01 PM
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Having been a "cedar rat" in my youth - salvaging Western Red Cedar from down logs & helicoptering them to a road landing. I can say based on your location & the grain appearance of your planks that it's Red Cedar...And given the tight grain & years of air drying that it's worth using it for a guitar soundboard...Find a luthier and have them pick the best piece...Sounds like a fun project!
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#9
03-05-2021, 07:16 PM
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Nearly all the Western red cedar I have cut for soundboards came from cedar siding that I bought at building supply retailers in the early-1980's. Back then, it was relatively easy to find old growth vertical grain boards that had enough clear areas to make perfect guitar tops. Times have changed.
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#10
03-05-2021, 07:34 PM
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#11
03-06-2021, 08:13 AM
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quarter sawn
KevinH, The gentlemen whom I learned from and all of my reading say guitar tops are made from quarter sawn wood. I often brought found wood to the shop to ask the luthier about. His response was and is, "Why do you want to start with a handicap?"
I continue experement with student grade wood. I have a fantastic baratone uklele with a western red cedar top made from old siding. It is quarter sawn. Those are nice pieces of cedar and a very cool find. They look too far off quartered for a good top to me. Best regards, Maurice
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#12
03-06-2021, 03:07 PM
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One of the best 14 fret Martin D-28's I have ever played is a 1937 with 45 degree grain in the center of the top. The grain gets more vertical toward the edges, but it is still not 90 degrees, evidenced by the lack of visible cross silk.
A cross grain stiffness test will tell the tale, and would weigh in the decision of what size guitar and what bracing would be appropriate. The reason coniferous woods rapidly lose cross-grain stiffness when the grain slants even a few degrees is related to the rectangular cell structure. These rectangles align with the growth rings, and a force that is not parallel will tend to distort the rectangles into parallelograms. Think of a house of cards. Hardwoods do not exhibit this property because the cells are more randomly arranged, and tend to be circular.
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#13
03-07-2021, 07:48 AM
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the one on top
I dont build expensive Instruments. I would certainly try the one on top if the face is ok.
John Arnold , What wood was the Martin 14 fret?
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#14
03-07-2021, 11:02 AM
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The D-28 has a red spruce top. But when I evaluate top woods, the properties of that top (particularly stiffness and density) are much more important than the species.
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#15
03-08-2021, 07:17 PM
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I like Cedar
Regarding cedar in general, my first new guitar (birthday present 30 years ago) is an economy Seagull S6dlx, cherry plywood back and sides, solid western red top. It has inspired two of my family members (Martin and Taylor owners), to buy ones like it.
The Port Orford smell will allways remind me of pencil shavings from back when a pencil was a quality item. Last edited by mauricemcm; 03-08-2021 at 07:27 PM. Reason: P.S.
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