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| Anyone not use side struts? http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=30294 |
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| Author: | PeterDeWitt [ Sat Dec 11, 2010 7:12 pm ] |
| Post subject: | Anyone not use side struts? |
Does anyone not use side struts to reinforce their sides? I am leaning towards not using them on an EIR guitar. Wanted some feedback before deciding to do so. Thanks, Peter |
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| Author: | Jim Kirby [ Sat Dec 11, 2010 8:05 pm ] |
| Post subject: | Re: Anyone not use side struts? |
What is the reason for not using them? Even if they never come into play, should they not be there? A real devil's advocate question that I don't know the right answer to.. Neither of my factory guitars (Larrivee L-09 and Larrivee Parlor have either back strips or side reinforcements, and neither have suffered for it, but would it have hurt for them to be there? I certainly haven't been so bold on my own builds. |
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| Author: | bluescreek [ Sat Dec 11, 2010 8:12 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I do use them . I prefer brown ribbon . |
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| Author: | PeterDeWitt [ Sat Dec 11, 2010 8:13 pm ] |
| Post subject: | Re: Anyone not use side struts? |
Yep, that is why I was asking, Jim; definitely not trying to start a debate. Like you said, I don't see them on every guitar and despite that, I have not seen a split side before personally . . . so I was just wondering if anyone had consistently not used side struts without issue. Peter |
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| Author: | Mark Mc [ Sat Dec 11, 2010 8:56 pm ] |
| Post subject: | Re: Anyone not use side struts? |
Side splits are one of the more common injuries that a guitar can suffer. It is easy to happen when it falls off a stand, or one of your kids/wives/alternate personalities isn't watching where they are going around the house, or you are gigging somewhere... And the fact that most factory made guitars don't have them is just for economy - and your hand built guitars will look that much more 'special' if they have this little bit of attention to detail. I like to make them with thin strips of spruce, like mini braces, tapering into the kerfing at the ends. But if you don't like the look of them you can certainly live without. |
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| Author: | woody b [ Sat Dec 11, 2010 9:00 pm ] |
| Post subject: | Re: Anyone not use side struts? |
The side struts I see alot of people using could do more harm than good. Ones that stop at the linings could actually cause cracks where they meet the linings. Wood expands and contracts across the grain. If a side shrinks a little due to low humidity the side strut won't shrink, since the grain is running the other way. IMHO cloth side struts are the only way to go, if you're going to use any. They were never intended to prevent cracks, just to keep a crack from spreading. |
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| Author: | Mark Mc [ Sat Dec 11, 2010 9:21 pm ] |
| Post subject: | Re: Anyone not use side struts? |
That is an interesting theory Woody - about the side strut causing a crack. I guess that it could happen - but has anyone ever seen it? I don't like the look of cloth ones as much, but they might be better for this reason. And you are right in saying that struts do not prevent cracks - just stop them spreading along the grain. |
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| Author: | gozierdt [ Sat Dec 11, 2010 9:30 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I like using wood side struts, and often laminate the struts out of 4 or 5 thin strips of alternating light/dark wood. I inlet the struts about 1/8" into the linings to avoid the stress-riser issue if the struts run just short of the linings. |
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| Author: | Jim Kirby [ Sat Dec 11, 2010 9:34 pm ] |
| Post subject: | Re: Anyone not use side struts? |
The ones I'm building now have the strut running all the way from top to back, or as continuations of transverse braces. it seemed like a logical extension of the problem of inducing a stress concentration at the end of a terminated side brace, but it's still an open question in my mind whether the right answer is to do nothing at all. At a different level - we are building guitars for sound, right? If customers decide to do something stupid and break them, that is their problem, right? Is it up to us to reduce the risk of them being broken? Just for discussion purposes, of course. |
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| Author: | bluescreek [ Sat Dec 11, 2010 9:40 pm ] |
| Post subject: | Re: Anyone not use side struts? |
they don't really ad much strength . They are more for crack control . I use them in design and often will inlay them . Those that came to my shop have seen Pearlzilla and the side supports inside that follow the inlay. It is over the top but it sets my guitars apart . Martin used a brown tape for many years . |
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| Author: | PeterDeWitt [ Sat Dec 11, 2010 9:52 pm ] |
| Post subject: | Re: Anyone not use side struts? |
woody b wrote: The side struts I see alot of people using could do more harm than good. Ones that stop at the linings could actually cause cracks where they meet the linings. Wood expands and contracts across the grain. If a side shrinks a little due to low humidity the side strut won't shrink, since the grain is running the other way. IMHO cloth side struts are the only way to go, if you're going to use any. They were never intended to prevent cracks, just to keep a crack from spreading. Woody, your answer about wood expansion was very helpful. Also, John, I appreciate your response about not adding significant structural support. I think I did not have a thorough understanding of not only their purpose (keeping cracks from spreading), but also their implementation. So thanks everyone from my end. Look forward to any further discussion. Peter |
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| Author: | alan stassforth [ Sat Dec 11, 2010 11:19 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I don't think any side reinforcement is necessary. Woody's right. I think. Tape might help, but if somebody drops their git, oh well. I thought the braces stiffened the sides, for tone. I've never used them, but I build weiss with 3" sides. After this thread, I might use them on wider sides, but make them thin, 1/8", not butting either top or back kerf linings. Or, make sure rh is low, so nothing bad happens in the future. Oh, I know nuthin'....... cept wood. It moves around a lot, especially when it's very thin. |
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| Author: | L. Presnall [ Sat Dec 11, 2010 11:29 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I'm apparently the odd man out here, but I don't use 'em...and, I hate to even type this, (don't wanna jinx anything  )...but, I've never had a guitar come back with a side crack...humidity control and well-bent sides are something I strive for and I figure if the "big houses" can do it, (leave out side bracing) I should be able to...and, as someone has already alluded to, if a guitar is dropped all bets are off...
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| Author: | Ti-Roux [ Sat Dec 11, 2010 11:35 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I use solid wood (spruce or sp. cedar) for my classicals. 4 bars sit on each side of the 2 big braces, and some more, smaller, around the sides. Well, i'm using this method 'cause it's my master's vision of the thing... but, honnestly, when i'll work by my own, I'll probably laminate my sides with a 2 or 3 ply, and only use parchemin tape to stiff it a bit more. That said, you could also don't use them at all, but even if your sides are perfectly Q-sawn and free of runout, they won't resist the tension and humidity changes, and they'll warp. Well, that not THAT harmful to the guitar sound but, if you take the time to build a handmade guitar, you definitly want it the best you can. Sides are one part of the guitar that is way more structural than acoustical. That's why i'm a fan of laminate sides. Add much more stability and rigidity to the box without killing that much sound. Francis |
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| Author: | SteveG [ Sun Dec 12, 2010 3:13 am ] |
| Post subject: | Re: Anyone not use side struts? |
Ah, learned something. Key crack: http://www.frets.com/fretspages/Musicia ... crack.html cheers |
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| Author: | Tai Fu [ Sun Dec 12, 2010 5:40 am ] |
| Post subject: | Re: Anyone not use side struts? |
What if you were to reinforce the side all the way by laminating thin veneers (the grain on the veneer would run perpendicular to the side grain) on the inside after the side is bent? Would result in a thicker side (and if it's already bent then it doesn't complicate any bending process) but it would be almost as resilient as laminated side. Or the thin veneer strip could be used BEFORE any kerfed lining goes in, to prevent the problem of side cracking where the kerfed lining meets the side reinforcement. If you dried out the guitar to where the side shrank enough to damage the side where the side reinforcement meets the kerfed lining, then it is likely a lot of other problem would have surfaced as well! Also I noticed some guitars do not have a backstrip, and they are usually found on inexpensive guitars. Some even have a backstrip in the wrong grain orientation! I think in these case the back and side may be laminated so things like backstrips and reinforcements are only cosmetic. But backstrip in the right orientation is required for all solid guitars because there isn't a whole lot of surface area for the glue to hold both pieces together, and the backstrip provides that extra level of insurance. It also gives reinforcements for back inlays that may be more prone to falling apart (because your back joint is only as good as the integrity of the back inlay). |
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| Author: | bluescreek [ Sun Dec 12, 2010 8:20 am ] |
| Post subject: | Re: Anyone not use side struts? |
Unless you put in one heck of a side support you won't gain much in side strength and if you do , mostly at the area of the brace. It is there just crack control. I use them and Todd points out a pro points. Tape is more for the vintage appearance. The cross grain glue joint can actually help cause a crack in rare occasions . They are not a 100% have to have but it does help when you bump a side . Martin used more of them with tape and only 3 with wood. Mostly like Todd mentions , at the more flat areas. One way to test this is to actually apply a measured force to the side with and without a brace. You may be surprised at how little a martin style does . A bathroom scale and clamp will tell you . The shape of the side will affect the strength much more than a 1/16 inch thick stick. A flat piece will fail pretty quickly , the support may let loose within 10% of the total or less , the curved piece with no support will blow the flat piece out of the water . |
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| Author: | meddlingfool [ Sun Dec 12, 2010 1:45 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I don't use them... anymore. The only side splits I've encountered have been one United Airlines guest, and one fellow who enclosed his guitar in a very flimsy gig bag and then left it sticking slightly out of a hatchback as he slammed the door. I don't think anything would have helped in either case... |
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| Author: | Andy Zimmerman [ Sun Dec 12, 2010 2:05 pm ] |
| Post subject: | Re: Anyone not use side struts? |
No side struts for me, but use a double side technique with the 2 layers epoxied together. |
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| Author: | unkabob [ Sun Dec 12, 2010 3:50 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I have not used them so far but I am considering using veneer (0.023") top-to-back and sanded under the kerfing. I am not sure what strip width would be effective. Bob 
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| Author: | Alan Carruth [ Sun Dec 12, 2010 6:18 pm ] |
| Post subject: | Re: Anyone not use side struts? |
I did some testing of side tapes several years ago. I got samples of nylon twill tape, and also the cotton-poly bias tape that I've been using. I made up cross grain wood strips, cut from failed sides, about 4" long, 2mm thick, and an inch or so wide (all the same, of course), and put tapes on them. I made strips of several types of wood, and had several samples of each type with no tape, with cotton-poly tape, and with nylon tape. I also made samples of each type of tape with Titebond and HHG. The tapes were glued on, and shellaced over, which is what I normally do. When the samples had dried for a few days I made up a long lever setup to break them. I put the samples across a couple of dowels an inch or so apart at a certain distance from the pivot, with the tape side down. I put another length of dowel across the sample in the center of the span, and then loaded them until they broke. To load them I used a can full of marbles, which I slid slowly along the lever. By recording how far out from the pivot it was when the sample broke, I could calculate the force required. Basically, any tape about doubled the amount of force it took to break the sample. The worst was the nylon tape, which tended to come unglued without actually breaking, as it did not stretch and the glue didn't stick to it well. The 'weaker' cotton-poly tape took more force, since you actually had to break it, and generally broke where the load was. The samples glued with HHG were stronger with either tape than the Titebond samples. I think that side tapes must have gotten their bad rep when Martin started to use that awful self-adhesive stuff. The thick latex adhesive allows the side to move and crack relative to the tape, so they don't really do any good structurally. The adhesive also dries out over time, and the tapes start to flap loose, with a lot of dust on the sticky areas. I used to fix side cracks for one local performer who had a Martin with those tapes every time he got back off the road. I finally got sick of it, removed them all, and replaced them with cloth tapes. He stopped having to come back for that particular repair. As has been said, if you use wood fillets you _must_ inlet them under the liners. If you don't the abrupt end of the fillet at the edge of the liner creates a stress riser, and if the side breaks at all, that's where it will break. That's the hardest place to fix it. I have seen a number of examples of side cracks that stopped at a tape. One maker points out that, in old guitars with side tapes, if they are cracked the tapes are also broken, and draws from this the conclusion that the tapes didn't work. The missing piece of information is how much force it took to crack the side. My experiment, and experience, suggests that the tapes do help, and I use them on all my guitars. I have seen guitars with wood fillets that had side cracks because of them. In one case, the crack ran across two fillets, and the fillets themselves were intact. These were deep sides of a relatively soft wood, and I have to wonder if the sides shrunk in low humidity across their depth, while the fillets, being long-grain, did not. It is pointed out that wood fillets are stronger than side tapes, and that is certainly true. My only rejoinder to that is that anybody buying a hand made guitar should at least try to take decent care of it. Stuff happens, of course, and we makers should take _reasonable_ precautions, but there is no way you can make a guitar bullet proof, and I think it's unreasonable of customers to expect that. |
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