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I know I have talked to many friends about grain orientation, and the effects/risks/benifits to selecting quarter sawn wood vs Flatsawn vs rift combinations(to flat or quarter). The reality is that many of the woods we prefer to use simply are becoming pretty much impossible to get in a well quartered two piece back. That said, some woods have a very close radial to tangential shrinkage ratio, and probably are very viable even with off quarter orientation. However most of the woods commonly used have closer to a two to one ratio at medium volumetric shrinkage making odd grain potentially more problematic.

So the question that comes to mind. When many of these woods could be selected in a well quartered orientation if a four piece back configuration is used. What are the real downsides to using a four piece back? How are the downsides offset by being able to select well quartered wood? Asthetically I don't really see a four piece back as a compramise, because a well joined quartersaw is very easily matched, and actually many figures(landscaped, spiderweb and so forth) are often drop dead amazing in smaller bits of wood.

So that is the question/ my thoughts. I was hoping I could get some feedback from others on the subject. I know the most common perception is two piece is better than four, even if grain is less ideal. I wonder why that is .

Rich

I have used four piece backs quite a few times, even when I had a board wide enough to make a two. But if the board is quartered on one side and flattenes out tword the other side I would rather just use the vertical grain part and make a four piece back. But I'm so old school I even like that old boring straight grained Brazilian Martin used to use.

Peace, Paul

What are the real downsides to using a four piece back?

I can't of think of any unless you are tryin to sell it. Then you will likely run into a number of traditionalists who perceive it as an oddity.

That said, there seems to be some talk about major manufacturers going to 3 and 4 piece tops to get better yield from the limited quantity of good top wood and I imagine that will eventually be accepted practice, out of necessity if nothing else. But you can make top joints next to invisible too.

As for quarter sawn being a huge advantage in backs, I haven't seen much to back that up. The way most people build, maximizing stiffness/weight ratio in backs isn't nearly as important as it is in tops. In theory, sure, the less a plate moves with humidity changes, the better. But most rift sawn and some totally flat sawn back woods move less with humidty changes than quartersawn top woods do. Seems to me that if "X" amount of movement is good enough for a top, then less than that is certainly good enough for a back.

Figure is a different story though. Too many variables to make generalizations.

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http://www.chassonguitars.com

When I see some dealers selling mediocre flatsawn backs just because it's big enough, it makes sense to have four piece backs. They often have more pleasing figure. Here's a nice four piece macassar ebony back from Bob at RC Tonewoods. At the time there was very little macassar that I could find, so this was a great option.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

That's nice looking Ken!

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

I don't have any problem with multi piece backs. It is much easier for me to find my own wood in 4-5 inch widths than spend 4 times as much to get a 2 piece set I can't touch and see first. Sometimes too you find wood that is just too good to pass up in smaller sizes! Like this Cocobolo:



People don't complain about all those Madrose sets LMI sold. I think if you can make the join either invisible to the average eye or make it decorative you are fine. I do wonder sometimes about gluing up quartered wood to flat sawn wood. Usually it doesn't happen because the grain doesn't match, but that is the only thing I worry about when matching plates.

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

Some claim that a well joined back doesn't really need a center reinforcing strip. Larivee doesn't use one, for example. I use one on my backs mostly because of tradition. Do you all use reinforcing strips on your four piece backs? Do you do it on every join or just the center one?

If you only do the center join and use well quartered wood, the fact that it is a four piece back might be almost undetectable.

If the pieces are wider than 5 inches then the joint falls outside of the waist on my small jumbo pattern and doesn't go the length of the back. So I only put in a cleat in the lower bout between the braces.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

I purchased 2 Santos Mahogany 8/4 boards today from Woodcraft. Each board will yield about 4 sets of backs and sides....That's 8 guitars. I paid less than 200 dollars for these boards...one of which is ribbon striped and perfectly quartered, WITH sapwood, and the other....well the other you can't really tell which way the grain goes....it's the most tightly figured board of anything I have ever seen. If I were to retail the sets that come from this one board, they should fetch about 350.00 each....but......

IT'S ALL MINE MINE MINE MINE MINE......

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

So is the only issue customer perception? Along the same lines why do you think a customer would feel better about a rift to flat two piece back, as opposed to a four piece well quartered back?

So far the responces are interesting to me. In the past I have sold two piece backs and on occasion I have offered a 4 piece. The four piece backs do not draw as much interest, and the value is greatly diminished(although that is kinda good because the price should be lower as availability is better, and wider boards cost much more) vs even a rift sawn back set. A well quartered 2 piece back set in a wood that does not generally grow large and is limited in availability(say a wood like Cocobolo or Zircote) will demand a significant premium.

Personally, I don't hesitate to use four piece backs, I find it much easier to get a great back set that way(and often the matching is so good you would have to get extreamly close and study a set to make a good guess at where the joints actually fall). It is almost impossible to find wood that would be even close to as nice as a set I can make from four pieces vs two piece.
This is a four piece for example;


Peace,Rich

P.S. Sniggly, Santos Mahogany is not Cuban Mahogany(I am assuming you must be thinking they are the same to arrive at those values). It is a wood that can be had in wide widths commonly. It is a very durable wood(much harder than Honduran Mahogany), and has a nice tap from what I have found. It is actually tuff enough that it is used for floors, and is so. You should get some very nice sets out of that wood

"Santos mahogany" is a trade name for Myroxylon balsamum and has nothing to do with mahogany other than the trade name. I buy it as "Balsamo". Sweet smelling, it's harvested for perfume oils besides making good flooring. Heavy!!!! Can be got retail for around $6 a board foot.

Just another South American hardwood with no tonewood history.

I got lucky and wandered through a lumber yard recently that had just stacked up a bunch. I spied a narrow board that had amazing flame and pulled it out for bindings. I then started digging and I walked out (well, hobbled out with all that weight) with about 60 bd ft of stunning flame and beeswing figure, 5" to 12" wide. I resawed a few sets and the tap tone is quite promising.

And yep, it sure does smell good. The dust in my shop vac perfumes the shop every time I turn it on.

Here's a closeup of the flame that doesn't do it justice.

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http://www.chassonguitars.com

Oh yeah?...well...I got some Cocobolo too!....

You guys are yucking my yum....

All kidding aside, I didn't think santos was cuban mahogany. It was way way way too heavy.

I shall consider myself on the 'cutting edge' of guitar making then...since it has no tone wood history....I will make tone wood history....I will be the tone wood history man.....errrrrrrr...atleast one of them. One day you will see a picture of me holding a piece of 'mahogany'.....in 'Santos'...Cuba...or...Venebrazanama....with a guitar propped up against my leg!!

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Kent, That looks wonderful. The Santos I have run across has a great look(nice and shiny), I bet that figure really jumps. The bits that I have tapped did seem very promising also(brilliant and focused, but not too harsh). I have been wanting to try it out for years. Only thing that seemed like a possible negative was that it seemed a bit brittle, but I have not tried it yet so I am not sure if that is going to be a problem.

Rich

I shall consider myself on the 'cutting edge' of guitar making then...since it has no tone wood history....I will make tone wood history....

I'll race you! Ah, nevermind, I'm too slow. Besides, I think this guy beat us to it http://www.mangore.com/bellucci_guitars.html

I can't find it now but he did have some Santos Mahogany guitars advertised. I doubt it would be great for classicals though. Too much damping and not enough brilliance. Maybe that's why it's not on the site anymore...

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http://www.chassonguitars.com

Rich, have you tapped guitar sized plates? The stuff I have, I would not call brilliant, in case you didn't notice the last post that I wrote before I saw yours

I would say darker, deeper and less woody than Hondo but less sustain than IRW. And a cinnamon nose and aftertaste...

I think it would make a nice dread, small jumbo or jumbo.

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http://www.chassonguitars.com

I don't know any luthier who has that perception, unless the conversation is about marketing issues. What I think builders should when they go four (or more) piece is explain that they took extra time and effort making additional glue joints in order to give the customer the best quality wood, and make it a small upcharge.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Since we are discussing grain direction (quartered or not)...Here are two examples.T

The darker billet for backs is not quartered...but how could you NOT use it? When you look at the end grain it literally runs in all directions.

The lighter board with sapwood is perfectly quartered but doesn't have near the character of the first. Incidentally both are 'Santos Mahogany'....stuff is really hard.

BTW...I totally agree with Howard...(wish I knew you better buddy). More work equals more pay...that's how I run my business here in Jacksonville.

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Kent, Yep I did see your post. The sets I have are just ruff back and side sets(I haven't thicknessed or trimmed them to a pattern). I found they had a tap that was more akin to sapele, although did not ring as long. Then again, after thicknessing closer to thickness I may find that changes. I have not sampled many bits of this wood though or built with it, so my impressions are based on a very limited sample. It certainly sounds like we are hearing something very different.

To be honest with you, the main reason I even cut up the couple sets I have was because the hardness and density of the wood made me curious to hear what it would sound like. Well that and the wood did not cost much so it wasn't really a big loss if I hated it.

Rich

Rich...to be perfectly honest...that is exactly the reason I bought it. I will get about 8 sets out of my purchase today...at around $20 bucks per set....and that includes backs, sides...even matching fingerboards should I like. I will also admit that I didn't do any research on it and actually thought it might be part of the......'mahogany' family....

That first board sure is going to make some beautiful sets though....can't wait.

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

The darker billet for backs is not quartered...but how could you NOT use it? When you look at the end grain it literally runs in all directions.

I still don't understand exactly what the concern is. Splitting? Nothing splits more easily than than old QS VG BRW (unless it's QS VG Cedar). If you have an axe and a choice of splitting a pile of straight grain wood vs. a pile of stump wood, what will you choose? If you have a 4 x 4 to split into kindling, how will you strike it? Parallel to the grain lines or perpendicular? Splitting is only parlty about differential expansion/contraction. It's also about split resistence.

I went through several sets of my wood wood last night including a piece of QS VG BRW, some stumpwood BRW, some flat sawn beam wood BRW, some flat sawn quilted Big Leaf, and some rift sawn wenge. By far, the piece I would worry most about splitting is the QS VG BRW.

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http://www.chassonguitars.com

Perpendicular.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I agree with Howard. If you look at the end of a piece of firewood, the checks are mostly perpendicular to the annular rings.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Yes, that's why I said 4 x 4 in that example and not green rounds. Properly dried lumber doesn't have those checks. The reason they appear is from the differential between tangential and radial shrinkage in wood that dries too fast. They don't split like that becasue that's the path of least resistence.

My main point is, in my experience, QS VG wood, even though it's more dimensionally stable, is more split prone and once it splits, it's likely to split severely. Also, in my experience, top wood is way more likely to split than back and side wood, even though it's always QS VG. I've never had a back split, including a guitar the guy left in his truck in the desert sun for a week. The top was totaled but the rift sawn back was fine.

Go cut two pieces of brace wood the same size, on QS and one flat. Try to split them. It's no contest. It will be dramatically harder to split the flat sawn piece. That's more true with some woods than others but it's generally true.

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http://www.chassonguitars.com

.....so the fact that I am going to use that crazy looking billet for backs is a good thing. That is what I take from this.

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There is no difference between the man that thinks he can....and the man that thinks he cannot.