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I've been looking over some wood at the local woodcraft store - there's a piece of curly bubinga that IS quartersawn that will make some great back and side sets. There is also a beautiful piece of Ziricote that IS NOT quartersawn that I still think would make some awesome sets. I also have a bunch of very nice looking slab sawn Cherry that could be made into some great sets - so the question is, is it OK to use non-quartersawn wood in the backs and sides?

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Mitch

YES!!!!!! Much of the figuring you see in back set is due ro riff, Flat or some other off quarter cut. Quilt is a prim example.

In Manchester, Mitch? I have been eyeing that piece too(ziricote)! I was going to cut a bunch of sides from it. Have you been to Parkerville (Harris)? I haven't had a chance to go yet.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

yep, Burton, that's the place - they just got that Bubinga piece in - there were two pieces of Ziricote there but someone bought one of them - I've been drooling over this stuff for a month now - guess I better get in there and pick it up - If I get there before you, do you want a set?

I haven't been to Parkerville Wood Products since it changed over from being Harris - but the school gets wood from there and it is pretty good stuff. I usually get my hardwoods from CT wood group or Irion in PA.

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Mitch

I believe that Ziracote is split prone, it has been in my experience, so I would be a bit more worried about flatsawn stock (especially for sides). In cherry I wouldn't use it just because cherry's cheap anyhow, and I can get all I'd ever want QS, but I don't think it's especially prone to failure.

For precedent on using flatsawn wood in a high-end guitar, see 90% of the BRW guitars being built this year...

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Thanks for the input Bob - I am making at least one guitar out of the cherry as I've had that wood around for a looooong time and feel this is the right place for it to go - and as you say, its cheap, and until I get more builds under my belt, I can use that stuff up - until the good zoot dries appropriately...

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Mitch

Quartersawn wood should be used whenever possible. It is more stable than slab or rift sawn, and more resistant to checking than slab sawn. The wild figured sets from slab sawing, runout, etc. are not desirable for any sonic or structural reason, despite being promoted by some dealers on Ebay and elsewhere. If you want quilt or birdseye then slab sawn is a necessary evil, but you do run risks of warping and checking.

Ziricote is check prone and ought to be quartersawn; it is available that way from guitar set suppliers like Hibdon, and show the best figure when quartered. Cherry is plentiful, so no reason not to find a quartersawn board. Bubinga likewise is available in wide quartersawn boards.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I agree with Howard, and this whole thing shows how bling and zoot are evidently more important to some builders than making good sounding, stable, long lasting guitars. Just don't be surprised when it bites you in the ass and you have to repair some once spectacular but cracked or warped instruments... I think too many people listen with their eyes. But then again, it's easier to build a mediocre guitar with fantastic looking wood than to build a simple and great sounding guitar...

Well, see there, that's why I asked the darn question in the first place...There was that little voice in my head that said, "Well, you can, but SHOULD YOU?" ...and I think I have the answer...Thanks all that responded...

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Mitch

So true...

I had a guy call me the other day about a BRW stump wood guitar he had bought from a very well know maker. He said there were cracks opening up all over the back and wanted to know if I was interested in repairing it for him. This is on a guitar he paid 11k for. I told him to call the builder.

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Dave Rector
Rector Guitars

With woods like bubinga and cherry that are easy to get in boards wide enough allways go for quarter sawn stock if you can.
as howard said it is much more stable than slaby wood and is inherantly stronger.
allway go for quarter sawn sides if you can becouse you need the stiffnes to stop the wood twisting etc once bent.
With woods such as mad rose it is allmost impossable to get quarter sawn backs and any reputable supplier will sacrafice wide quartered boards for the sides.
Slab backs are not as much of a problem espesialy with the more stable woods like most rosewoods.
i would say leave the cherry for in preferance for quartered stock.
go for the quartered bubinga it will make good solid guitars.

If i cut slab sawn backs i will make sure at least the jointing edge is on quarter that way it will have the strength where you need it most and should help with stability issues.

joel

Is there any allergy problem with Bubinga?

There is also the issue that flat sawn sets won't be well book matched. The grain pattern will be different on each side of the back seam-a streak of color that is one inch from the center seam on one side might be two inches or more from the seam on the other side. It also makes it hard to match the sides at the butt. Stick with quartered or close to it.

Paul

For what it's worth, flat sawn Brazilian moves almost exactly the same amount with changes in humidity as quarter sawn Sitka.

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http://www.chassonguitars.com

Kent, I've seen a fair amount of flat/rift sawn Braz that curls like potato chips before and after joining. That stuff needs a lot of attention. Sure, once braced it tends to retain its shape, but often not.
Why would one bother with that stuff if he doesn't have to is beyond me.
It's always possible to take a bookmatch and eliminate the flatsawn parts by making a 4-piece back.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

From what I have seen with Zircote it is more prone to split with the grain. Well quartered splits in some places(worst ever had strong medulary rays, perfectly quarted), however it is pretty easy to repair and you move on. I have never had problems with flatsawn. I think it is just the nature of the wood to be prone to cracking. It seems like these issues are initial drying issues, after dry and the issues are repaired, the wood seems stable and no more prone to cracking than other woods of similar density.

The ratios between radial and tangential shrinkage are what they are and wood will react accordingly. Longtitudinal shrinkage is slight, but when you start twisting the longtitudinal, as well as rolling from radial to tangial in relation to the face of your surface your going to get the potential for wacky movement. A little off or gradual transitions seem to be less problematic. Of course there is all sorts of wacky grain in figured(curly, quilted, flamed or what have you), and there is also potential for wacky changes there also. Add all the craziest of mixed up random grain patterns and you get burl. All that said people use Burl, crotch, sap/heart, curly, wavy longtitudinal, rolling quarter to rift to flat, all the way to dead on quarter clear vertical grain wood. I guess it all depends on what risks you are willing to take in the persuit of a look.

Rich

I don't think that blanket condemnations of "stump" BZ are reasonable. I've seen a lot of the stuff...and I have a bit of it...that is stable and flat and fine.

Wacky beautiful wood is probably best used in plywood...Oh, I meant double backed and double sided...guitars, laminated nicely with epoxy.

Besides working and stability issues aptly described above, I prefer quartersawn (read plainer) wood for aesthetic reasons.
An elegant dark straight grained back and side set will allow you to create any aesthetic you like. Whether it will be one of restrained elegance using a simple binding and purfling scheme, or, a maker's statement with elaborate marquetries or abalone.
As beautiful as some of the figured back and side sets can be, they should not become a crutch which will divert you from developing and refining your design aesthetic.

IIRC traditional birdseye figure is expressed mainly on-quarter.

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The member formerly known as erikbojerik....

Very good points by Rich. Look at a table of tangential (flatsawn) shrinkage values first. If the percentage is relatively low, (say, under 6%), that wood will probably not be problematic to use flatsawn (though the sides may be more temperamental to bend properly and keep flat.) If the percentage is slightly over that, then I would also look to see what the ratio is between the radial (quartersawn) percentage in comparison to the tangential. If they are relatively close, again, I would be OK with using the wood. But anything with a high tangential shrinkage value is just asking for trouble, especially in wide-backed instruments.

As a symmetry lover, I'm also with Paul on the aesthetic "flaw" that flatsawn wood does not bookmatch well.

I would take exception to the word "burl" being included in the list of wood that could be considered for use in instruments, unless we are talking about an incredibly stable wood (low radial AND tangential shrinkage values) with an incredibly close relationship between them. Mesquite is the only one I know. Even with that level of stability, the curly, swirly wood fibers in burl are short, and that makes the wood more delicate. I would say that burl should be reserved for laminated construction elements only.

Erik, Birdseye is flatsawn.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Dennis,
Looking up shrinkage values is a good idea. I have found my woodworkers handbook(USDA) to be a handy resource. If you have a copy (or I am pretty sure you can track one down for free on the web), take a look back in chapter 12 for dimensional change info (post drying, the chapter refers to changes between 6-14% moisture content). Chapter 3 has information on drying values from green to overdry(which is what I see most often).

One wood that I have always been impressed with in terms of stability has been Limba. Looking at the drying tables it tells me it has a radial value of 4.5 and a tangential value of 6.2 (as compaired to Mahogany @ R=3.0, T=4.1). Both have pretty great balance, but Limba still shows higher shrinkage values. From my experience with limba when dry and stable, it has been bullet proof (I would say more so than Mahogany even). Looking back at chapter 12, I noted that Limba has a coefficient of change on the radial of .00151 and tangential of .00187 and Mahogany Cr=.00172, Ct=.00238. Both extreamly stable and low shrinkage numbers, Limba moving a bit less after drying and subject to changes in humidity. So based on a 16" wide board Limba would change .0242" in the radial vs .0299" in the tangential(for every percentage of increase or decrease in moisture content), Mahogany radial .0275" vs tangential .0380" (again for every point of increase or decrease in the moisture content). All looking pretty reasonable. Looking over the tables, I see Tanoak has a much wider ratio and higher shrinkage values. Tanoaks Cr=.00169", Ct=.00423. Using the same 16" wide board change in radial would be .0270" (similar to Mahogany or Limba), the tangential would be .0677"(better than 1/16" per point of moisture change). That could be a very significant difference, and well quartered Tanoak would be much safer, as well as a wood you would not want to have rolling wacky grain in.

Thanks for making me open the book and do a little more homework Dennis . Now I better go grab a coffee, and cut some wood


Rich

Just found the chapter 12.

http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/ch12.pdf

Edit: here is the whole thing: http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/fplgtr113.htm

Hi Rich,

Yes, I have seen that chart before. Someone here on the OLF (was it you?) has corrected me in the past from relying strictly on the 6%MC tangential and radial shrinkage values, citing the same reference. I can see that the values shown in the (much more complete, by species) tables at 6%MC do not have a linear correlation across the board to the values of movement in-service. I sure do wish there was a complete, modern chart showing the values of dimensional change in-service for more than just those 25 species. It would be especially valuable if the chart included all of the common imported species as well as at least some of the "lesser known" species that are starting to gain the interest of luthiers and furnituremakers. In fact, other than Limba and Mahogany, I don't see any other species within that group of 25 that will help much when shopping at my tonewood dealers.

So, when considering Cocobolo, Bubinga, Shedua, Movangui, Satinwood and other species that may be from billets that are off the quarter (or even flatsawn), I have to rely on the 6%MC tangential shrinkage charts.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Dennis,
I think both table really provide you with a good bit of info to work with (after all these are all general propertise, not something you want to take as absolutes). Woods that generally have high shrinkage values in the tangential would be wise to opt for quarter, even if the green to overdry are not going to be spot on they will be fair indicators. If you see a wide difference between radial and tangential it would make sense to opt for as much uniformity as possible. One constant though will be longtitudinal, which will always be slight compaired to cross grain (irregardless of whether it is more flat or quarter). I would imagine that would be a first consideration, as a body will always be longer than wide. Either way I like to rely on how the wood reacts when I work with it and how it reacts after it has been stored for a while. First hand feedback is always the best way to get a better feel for these things, before I decide to use it or not.

I don't think I have ever mentioned chapter 12 before (actually I usually am more of a reader, than poster), you must have been chatting with someone else about this before.

Peace,Rich