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hi

just looking for a bit of inspiration for an often overlooked part.

Any cool side struts or ideas

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There was a good discussion of functional considerations regarding side braces in this thread: http://luthiersforum.com/forum/viewtopic.php?f=10101&t=50109&hilit=side+braces

It made me change my approach for side braces on my guitars.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Don't have any photos to share at this time (not at home) but you don't want to abruptly end the struts at the lining because that causes a stress concentration or stress riser.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Looks like the general consensus would be to not have any. That's what I'm taking from this thread when I build mine.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I think the general consensus is that you should have them and should think about how you install them. I have one of those old Martins that don't have them and it has the infamous key crack. So whether you do little strips of linen, simple pieces of scrap cutoffs from your back (which is what I use) or some elegantly scalloped ones like shown here I think it would be a mistake to omit them.

I advocate them or anything that can stop a side crack from propagating. You just don’t want to create another problem.

I’ve been doing fairly heavy stiff side struts like in the photo & feel they benefit the guitar but now I’m starting to rethink them after reading a comment by Bruce Sexauer where he said they can come loose over the years because of the cross grain gluing. He uses the traditional cloth side strips, FWIW.

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I view the side braces primarily as crack stoppers. I used to put four side braces on each side and the braces were about 3/16" thick, butted to the kerfed lining, rectangular in cross section and chamfered a bit on all four edges. After reading the other thread on the topic, I was persuaded that butting the thick-ended side braces to the lining could actually be increasing the risk of cracks if the sides took a good whack. And those would be hard to repair cracks. I wasn't willing to go as far as letting the side braces into the lining so I went with a thinner side brace that's oval in cross section and tapers gradually down to nothing at each end where it meets the lining. The shape and dimensions are based on the side braces in my '51 L-4c. Also based on that thread, I reduced the number of braces to just one in the flat stretch between the waist and the lower bout with the reasoning that that's the weakest section of the sides because of its length and it's flat. That's my story and I'm sticking with it, at least for now.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Nice clean work Jay!

My favorite style is where it's incorporated into laminated linings, where the first layer is interrupted by the side struts which go all the way from top to back, then are capped by the next two continuous layers.

Someone here posted a pic of that recently...

I have been doing kind of a hybrid of that method.
Side struts are full depth, solid lining in between and standard kerfed over the lot.

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My memory is so good, sometimes I remember things that never happened.

That's slick. How thick are the struts?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

That’s exactly how I do it. Here is a lousy picture but it is the only one I can find just now. There are pros and cons to every method and this one is no exception.



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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

75-80 thou. Usually same as the sides

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My memory is so good, sometimes I remember things that never happened.

Bryan,

What do you see as the downside of that, other than the time it takes?

I used to do side braces but now I only do if the sides are really thin, and I rarely use really thin sides anymore. As others have mentioned, that might be a pretty picture in the OP but it's not a good idea to do it that way. I have direct experience with that as one of my guitars developed cracks right at the end of the side brace. So for me so far it's side brace = 1 no side brace = 0. I'll stick to no side braces

Anyone bother with side struts when doing laminated sides? I’ve been doing solid linings on the last few following Burton LeGeyt’s tutorial. On the next build I’m doing laminated sides for the first time. I don’t know that side struts / braces are even needed.


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1) As you say, it takes more time. That is not an issue for me, not being in a production environment.
2) There is some concern that the cross grain brace may create problems with humidity changes. I'm not sure how likely this is but I suspect that, given the narrow width of the sides, an RH problem that splits them will likely have caused bigger problems with the top and back.
3) It has been proposed that the sides shrinking could cause the braces to push on the plates or bindings because they don't get shorter. I'm not sure how much of an issue that really is.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I have been doing the same as J with just one unless the sides are thin although mine go full length and as thick as the linings, with the Linings being segmented.

Bri, that's the first time I've seen your method and I like it! The only thing that seems tricky is keeping the two the exact same height. Any trick to that? Also, being as thick as the sides, do you need to bend them first? Or just use softer wood?

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Pat

I was wondering the same about keeping the heights the same. Looking forward to the answer.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

"Anyone bother with side struts when doing laminated sides? I’ve been doing solid linings on the last few following Burton LeGeyt’s tutorial. On the next build I’m doing laminated sides for the first time. I don’t know that side struts / braces are even needed."

I still sometimes use side tapes on laminated sides. But my method of laminating matched veneer makes the wood act like solid sides so it is still subject to cracking from drops and bumps. I thought about using drywall mesh fabric between the layers in a "rip stop" fashion - but only thought about it and have not done it yet. It seems like it would provide a continuous crack stop to the lay up and not be visible otherwise.

so what thickness would you leave the sides to avoid struts and still be able to bend okay

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Bryan,

To point 3, you could easily leave the 1/16 short of top and back...

The type of damage that jfmkenna showed is why you need to inlet the side braces into the liners.

I used to wonder if side braces causing cracks was simply an academic issue, but then I saw to guitars with just that sort of damage. Both were imports, with rather soft B&S wood and tall sides. They had cracks in the 'flat' part of the side below the waist in about the center of the side, that ran right across the brace in either direction.

Side tapes do a pretty good job of stopping cracks from running. It takes something like 50%-60% more force to break a piece of side wood with a tape on it than one that has no tape, from my tests. Usually the tape breaks where the side does, which seems to some to cast doubt on their utility, but, of course, when you see an old cracked guitar you don't know what it took to do the damage. I have seen them stop cracks. The main problem with them is that air and moisture can break down the glue. I use hot hide glue to put them on, which is easier than Titebond and stronger in my tests. THen I shellac them to keep the air away from the tape. We'll find out in 75 yeas or so how well it worked.

This is kind of timely. A circa 1886 Benary parlor guitar just arrived and it has four side braces, two on each side - thin pieces of BRW between the top and back kerfing. One of them is about half way around the lower bout, the other on the upper bout near the waist. It very effectively stopped this crack from running any farther

What I have been doing is ripping 3/4” off each side prior to bending, typically I cut all my own sides to 6”. I shape these 4 pieces in the bender, if I planned far enough ahead I could do my binding at the same time. The open box in my pic used mahogany thined to around .080”.
After end blocks are glued in and an approximate radius is established, the struts are glued. I then cut the bent linings to approximate length and fill in the solid lining between the struts, but the pieces are not cut at 90 degrees due to the dome. I usually just sand in the angle as it is only a degree or two to get a nice fit to the struts. I plan for about a 3/16” proud margin between the 1/2” wide kerfed and the 3/4” wide solid. Maintaining a consistent margin is near impossible but not really that noticeable since you cannot see all the areas at once nor any of the top. A light chamfer or radius sanded in by hand on the inside edge prior to gluing gives a nice final touch. This does make for 20 more pieces to be glued in, but probaby only adds another hour or so in time.

B

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My memory is so good, sometimes I remember things that never happened.