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I realized this afternoon that I made a big mistake when I cute up my brace stock and braced my back. This if the first time I have done the bracing from rough stock, and so something was bound to happen. I just wish I would have caught it before I glued everything down. I oriented the braces wrong on the back, so now I have run-out on the ends of the braces. Does this warrant removing the braces and starting over? The pictures below will hopefully give you a better idea of what I am talking about. If I need to take off the braces any tips on the most efficient way to do so? Thanks for any input.

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--Kyle Burner--

Yes, I'd remove them and put new braces on.

Use a small block plane to get most of the material off, then go to a scraper to get the rest.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Well, for back braces, I'd leave them as they are. The only way your mistake might do tricks on you is if your guitar receives a hit from the back. Otherwise they will hold.

If you really want to take them off, the best way is to gradually chisel them out.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Hey Rod, I heard somewhere that 'great minds think alike'.

Does that mean we're both dumb?

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

No Alain, I'm pretty sure you're much smarter than I am.

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My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Awwe! You're too kind...

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I'd remove them.......

According to Somogyi, wide grain spruce is actually stiffer when flatsawn, while medium and narrow grain are stiffer quartersawn. Interesting! I can see if I can find the article tomorrow, and see what he defines as wide vs med vs narrow.

I would remove them too , a heated spatula will soften the glue ( assuming you used some type of wood glue )and slip right in between the braces and your plate . Jody

Not long ago, I believed that orientating the grain like that would make the brace more split prone. Like most people, I thought wood splits more easily parallel to the grain (tangentially). Turns out, that's not necessarily true. They might be less split prone when flat sawn like that.

After milling up some samples from the same board I found that flat sawn (like in the photo) splits less easily. And looking closely at the pieces I broke, there were a lot of little fibers (medulary rays?) that span across the grain in that orientation that keep it from splitting. Give it a try.

I looked through Hoadley (Understanding Wood) and did a bit of searching on line but have not come up with much to quantify that. My guess is that it differs from one species to the next but I'm pretty sure this holds true for spruces and cedars and anything with lots of medulary rays.

As for stiffness, mostly what Lars said. Somogyi found that in less dense and medium dense (subjectively defined) spruce, flat sawn was stiffer than quartered. In dense spruce, stiffness was similar no matter what grain orientation.

This all begs the question, why did it become standard to use quarter sawn bracing?

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http://www.chassonguitars.com

The generally accepted notion that it is more stable than flat sawn I think. I always thought that it was the main reason quartersawn is used throughout a guitar more than stiffness.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Bouchet used flat-sawn stock for one of the top UTBs. I've seen at least two older Martins (0 & 00 18 style) with flat sawn stock for the back braces, one even had a flat sawn neck. IMHO it doesn't matter for ladder braces.
If in doubt why not wait a few days and see if the back keeps its radius OK, as it should?

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

I have done quite a bit of restoration work on instruments dating back to the 18th and 19th century even a couple from the 17th century, there seems to have been no great urge to use QS braces on their instruments then and guess what, they have survived centuries just fine, indeed traditionally soundboard braces on lutes (including mine) were made flat sawn, tall and thin. You could argue that in fact they are QS but glued on the flat sawn edge, and I have seen 17th century ones that as good today as when first glued on.

Anyway, back braces are generally structural rather than tonal, so if they are holding the dome OK, I think I'd just leave them, check on them in a hundred or so years I bet they'll still be fine.

Up to you though.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

For plates, yes. But for braces, dimensional stability doesn't really matter.

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http://www.chassonguitars.com

I've always thought that one reason for using QS braces is that they would glue better. Glue penetrates and bonds better to the softer earlywood part of the grain then to latewood. On a QS brace the latewood makes narrow (usually) lines that run along the gluing surface, while on flat sawn surfaces the latewood can go all the way across the brace and extend for some distance along the length. This would make a weak patch in the glue surface. I have to say I have not put this to a rigorous test yet; if I've noticed differences in the course of repair work it may be that I was primed to see them. I wonder if the Forest Products Lab has done anything like that?

Alan, I've seen plenty of two and three hundred year old flat sawn braces and bridges that were still glued just fine, I've noticed no difference between flat or QS as to whether they have come unglued. That said, they were all glued with animal glues, I don't know if the same would be true for PVA or Aliphatics.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Quarter sawn is better for strength it's like a beam,hard to bend .Rift sawn is like plywood,it bends easier.That is why neck wood is almost always quartersawn.I don't want my braces bending as they are for support.So i always use quartersawn for braceing

Kyle, I did the same thing you did on my first. The two bottom braces on the back were flatsawn. When I was looking at the end of the chunk of wood I saw the marks made by the saw and thought it was the grain. I didn't realize it until I had to cut the top two back braces. I glued them in anyway not knowing if I'd have enough brace wood to finish.

Thats been about five months ago when I glued them in and glued the back to the rims and they still are holding their radius just fine. I also used hide glue but I don't think using Titebond would matter.

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

This is why this forum is so valuable. Thank you all for your responses I braced the back almost a week ago and it is still holding it's shape so as far. Being that it is still holding the radius I am starting to think I may go with the braces as is.

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--Kyle Burner--

I'd leave em be. Especially on the back I don't think it'll matter that much. On the top I'd suggest QS orientation, but here again you'll probably b fine regardless.

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John Mayes
http://www.mayesluthier.com

I have seen many older martins that are the same way. this is your guitar and if you are the kind of guy that this will eat you up , them pop them off and replace them. It is easy to do at this point and you can do it that it won't be seen
john hall
blues creek guitars

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I wouldn't mess with taking them off and replacing. But as someone said, if it bothers you change them. I doubt will have any problems on them as back ladder bracing. Top, would replace them.

I think you're fine....

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Well there you go Kyle - I was rong...... But this is why I wanted you to post this on the forum because I thought it was a gray area that could go either way. Build on dude

No hesh I don't think you were wrong, after reading all this and thinking I think it is a very gray area. The back will probably be weaker given the orientation grain, but given that the back is holding form I think that the strength of the braces will be sufficient for their purpose. More than one thing went wrong yesterday with the build I guess we all have our bad days. Just gotta keep moving forward and learning from all my mistakes.

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--Kyle Burner--