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  #1  
Old 09-07-2017, 05:07 PM
rgregg48 rgregg48 is offline
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Default build question for the luthiers

I have noticed more luthier built guitars
in recent years , that had no side braces at all.
One builder told me he stopped installing side braces because
he felt they did function very well, in stopping side cracks.
i assume some builders feel this way and some don't.
i always saw them in Martins,, Taylor does not use them,
but custom builds?
Thx,
Rick
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Old 09-07-2017, 05:45 PM
virob virob is offline
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A lot of luthiers are using double sides.
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Old 09-07-2017, 06:26 PM
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iim7V7IM7 iim7V7IM7 is offline
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Some luthiers use ribbons to reinforce and others laminate their sides...
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Last edited by iim7V7IM7; 09-07-2017 at 07:00 PM.
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Old 09-07-2017, 07:14 PM
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nacluth nacluth is offline
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We still use side braces, but we don't laminate our sides. Actually we have laminated our sides a couple times for different reasons, and we still used side braces because we like the look...and you never know. Working at a repair bench and fixing plenty of cracked sides, side braces work. Not perfectly, but they can stop substantial cracks from continuing. One (the only one) guitar that we worked on without side braces cracked from block to block. Not enough evidence to draw a firm conclusion, but my bet is the crack would have been much less with reinforcements.
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Old 09-08-2017, 11:30 AM
Alan Carruth Alan Carruth is offline
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I've been using cloth tapes. My tests indicate they add some resistance to splitting from impacts at the tape, and also help keep cracks from running along the side.

I have seen two guitars with side cracks that I attribute to the use of wood fillet braces. They were both imports, from the same company. The sides were solid wood that was rather soft, and they were quite deep. I think the damage was caused when the wood fillets would not shrink in length as much as the sides would shrink in depth in the low humidity we see here indoors in the winter.
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Old 09-08-2017, 11:44 AM
redir redir is offline
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I started off doing side braces but I don't do it much anymore unless the sides are really thin or in an as needed kind of basis. The use of side braces has it's pluses and minuses and over all seems to equal zero, so I don't bother with them. They might stop a crack from propagating but if a crack propagates through one then they make the repair much more difficult. I don't see a problem with a crack being aloud to run as far as it's going to go. A side crack quickly attended to is not really any more difficult if it's 3 inches long or 7 inches. I also like to use spool clamps to tighten the sides together when fixing cracks, something side braces would resist against.
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Old 09-08-2017, 11:53 AM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by Alan Carruth View Post
I've been using cloth tapes. My tests indicate they add some resistance to splitting from impacts at the tape, and also help keep cracks from running along the side.

I have seen two guitars with side cracks that I attribute to the use of wood fillet braces. They were both imports, from the same company. The sides were solid wood that was rather soft, and they were quite deep. I think the damage was caused when the wood fillets would not shrink in length as much as the sides would shrink in depth in the low humidity we see here indoors in the winter.
Alan, what glue do you use?? The older Martins I see in my shop with ribbon bracing invariably show ribbon delamination to some degree or another. (Not trying to compare your hand crafting to Martin's factory operations.)

Thanks.
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Old 09-08-2017, 01:00 PM
Howard Klepper Howard Klepper is offline
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I've moved away from side braces, but there are plusses and minuses.

The wood braces add rigidity which is good for volume since it keeps vibration in the top. They probably do better at stopping a crack because they are more rigid.

OTOH, wood braces can cause cracks, because they run across the grain of the sides and won't allow the sides to expand and contract as much with humidity change. And cloth braces do better at preventing trauma cracks from originating, because they allow the side to deform and spring back when it is hit.

It's important that wood braces be let into the liners to avoid creating a stress riser where they meet the line, and also that they not run all the way from top to back because they will push out on the top and back when the sides shrink from low humidity.
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Old 09-10-2017, 04:00 PM
Alan Carruth Alan Carruth is offline
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I use hot hide glue on my side tapes. I did some tests of different tapes and glues, and found that HHG was a little stronger. It's also easier to use.

The really old delaminated tapes were, of course, put on with HHG, which does break down when exposed to air over the long term. I've been putting a few coats of shellac on the exposed parts of the side tapes (they run in under the liners) to counter that problem. I put on enough to build up a little bit of gloss, sanding very lightly between coats (three or four, maybe) with #400 paper. We'll find out in 75 years or so whether it worked...

Martin used some sort of self-adhesive tapes for a while that resembled the stuff they used to use for bandages. They had a thick, sort of latex adhesive, and this rendered them practically useless in stopping cracks, even when they were stuck down. Over time the adhesive dried up, and the tapes came loose, although, of course, since they were installed before the liners they didn't come out. What they did do was flop around and gather a lot of dust on the still somewhat sticky adhesive.

I had a repair customer who traveled a lot with a Martin Dread. He'd stop in every three months or so with a new batch of side cracks. Finally I got tired of it, ripped out all of the old self adhesive tapes, cleaned as much of the goo and dust off as I could, and replaced them with strips of linen between the old tape locations. It worked: he stopped coming by for side crack repairs; just the occasional top crack donated by the airlines.
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Old 09-12-2017, 06:17 AM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by Alan Carruth View Post
I use hot hide glue on my side tapes. I did some tests of different tapes and glues, and found that HHG was a little stronger. It's also easier to use.

The really old delaminated tapes were, of course, put on with HHG, which does break down when exposed to air over the long term. I've been putting a few coats of shellac on the exposed parts of the side tapes (they run in under the liners) to counter that problem. I put on enough to build up a little bit of gloss, sanding very lightly between coats (three or four, maybe) with #400 paper. We'll find out in 75 years or so whether it worked...

Martin used some sort of self-adhesive tapes for a while that resembled the stuff they used to use for bandages. They had a thick, sort of latex adhesive, and this rendered them practically useless in stopping cracks, even when they were stuck down. Over time the adhesive dried up, and the tapes came loose, although, of course, since they were installed before the liners they didn't come out. What they did do was flop around and gather a lot of dust on the still somewhat sticky adhesive.

I had a repair customer who traveled a lot with a Martin Dread. He'd stop in every three months or so with a new batch of side cracks. Finally I got tired of it, ripped out all of the old self adhesive tapes, cleaned as much of the goo and dust off as I could, and replaced them with strips of linen between the old tape locations. It worked: he stopped coming by for side crack repairs; just the occasional top crack donated by the airlines.
Thanks Alan. Gotta write a few more words otherwise "thanks Alan" is too short to post. ;-)
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  #11  
Old 09-12-2017, 07:20 PM
printer2 printer2 is offline
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Quote:
Originally Posted by Ned Milburn View Post
Thanks Alan. Gotta write a few more words otherwise "thanks Alan" is too short to post. ;-)
I do a string of periods and then on the next like I say,

..........

OK.



I know this is cheating, one of my vices.
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