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I've always used sticks between the kerfing on ribs, but have been thinking of trying tape. What kind of glue are you using and how do you keep everything clean inside? Do you run the tape under the kerfing (glue it on first), or between?

Thanks!

Hanns: Would have to think that cloth side reinforcement would have to be a bit of a tone sink as compared to wood braces.Also would not be as stiff. Not sure if that is good or bad.Maybe wood would stop cracks better then cloth. I've also wondered about life expectancy of the various cloths. Throwing this out to see what you and other folks think...!
Tom

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A person who has never made a mistake has never made anything!!!

I use cloth tape. Martin does. Just don't use cotton tape as cotton rots. Linen is best. I am sure that tape is best,because gluing wood onto cross grained sides is going to put a lot of stress onto the joints from the sides responding to humidity. The glue makes the tape more rigid,and I can't see it being a tone sink. I am sure that it stops cracks better,and you won't find it coming loose and buzzing in the future.

When Wayne Henderson was here in Denver last year, he talked about using cloth tape. If I remember, he said 1) Martin uses it, and 2) Wood is stiff. It braces the sides and keeps them from flexing. Cloth tape keeps them from flexing in (concave from the outside of the body), but allow them to flex out.

Makes sense to me, but I don't understand why that would be better.

Mike

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Mike Lindstrom

I have an answer for Hanns? Will wonders never cease?

What I have read on the tape subject is to use natural linnin, glue it to the sides with hide glue and then glue the linings over it. I saw a picture of someone applying tapes between masking tape to keep the glue from getting where it doesn't belong. If you are an AR gluer like myself, I would put the linnen on after the linings.

Steve

Seems to me that if you are reinforcing the ribs to add stiffness, wood will do a better job. If you are doing it to keep splits from spreading, wood may be better for that too although I haven't actually tested it. The Martin style don't do a great job of either from what I've seen.

As for humidity related problems with cross grained gluing, I'm not sure why one would glue a brace across a 15" back and not a 4" side.

I remember a post by Alan Carruth about a method of using tape that sounded more substantial than the traditional Martin style. Can't remember if it was here or on the MIMF.

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Ahh, what I thought, mask it off and use hide glue before kerfing. S'pose you could even use that Franklin Hide crap...
Thanks for the answer Steven.

Tapes have more uses than just the Nixon White House....

Yep Martin uses them, Gibson has used them, and a host of other builders be it fact*ries or individual dudes and dudettes use tapes too.

The purpose has nothing to do with adding stiffness but the tapes are there to hopefully arrest the travel of a crack if a crack occurs.

As far as being a potential tone sink the highly prized pre-war Martins used side tapes.

I agree with my buddy George that linen is a better bet but difficult to find. I use 50/50 poly and cotton and I am not overly pleased with it... The poly does not absorb glue being basically plastic and as George said linen will last over time better than cotton.

There is a toot by Todd on installing the tapes with HHG and it's excellent. I did a toot but it's now lost on installing them with Titebond and my toot was even more excellent - just kidding...

Lastly the tapes are available in the crappy 50/50 stuff that I use at fabric shops and you wanna ask for bias tape which I guess is used in sewing.

And really lastly install the tapes right up to the edge of your rim and then glue the kerfed or solid lining right over the tapes. As always what ever you use wood or tape or both in some combination stopping the supports at the linings is not as good a practice as continuing them under the linings.

SO..... We are in the " if martin does it ,it must be better" mode...?? Not sure..?
Tom

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A person who has never made a mistake has never made anything!!!

I use linen side tapes. I don't see how they could be a tone sink, but maybe I'm missing something. (I might even be missing a joke LOL) I use HHG, and install them all the way to the edge, before I install the kerfing. I believe this gives the best defense, either against cracks, or cracks spreading. IMHO anything, cloth or wood, that just goes to the kerfing isn't doing any good. I've seen (pictures of) a couple Martins with cracks halfway around the rim right at the kerfing. I used to use .200" X .200" Spruce or Mahogany strips that I installed before the linings, and then butted the linings to them.


I use warm water and vinegar to clean up the glue around the linen tapes.


I don't pay much attention to how Martin, or anyone else does stuff. There's alot of great guitars out there with no kind of side reinforcement.

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I didn't mean to say it, but I meant what I said.
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These aren't braces, they're crack stoppers, more like the thicker fibers in ripstop nylon than stiffeners. Probably anything well-glued to the sides that interrupts the propagation of cracks along the grain lines would be fine (though some are more attractive than others). And yes, they ARE important, as any experienced repair person will attest. The Martin-style linen strips work; so does wood. Just be sure to extend the strips under the linings or at least butt against them: it's hell to repair side cracks right next to the lining.

I didn't mean to infer that Martin's way was the only way. They HAVE been at it a long time,though. I have used wood many years ago,and now feel that cloth does a better job of stopping cracks.

In the 18th.C.,harpsichord makers used linen strips TORN from cloth under the glue seams beneath their soundboards. Looks terrible,but they weren't stupid. The uneven edges of the cloth keeps cracks from developing along the straight grains of the spruce,where the uneven cloth strips are glued. The dried glue pulls,and the spruce could be opened up if nice even strips were used.

We are dealing with gluing ACROSS the grain here,so straight cloth is o.k.. Why can't you cut linen strips if you can't find seam tape ? after it's glued down,it isn't going to fray.

As for glued on wooden back braces,I guess we have no choice there,do we? Those are braces. The linen strips are for holding cracks. The curves in the sides tend to hold the surfaces of the sides straight by themselves,unless you did a bad job of bending them by boiling,or something.

Haans,

I've seen cracks that stopped at the tape, and some that have gone past, but I think it's worth doing.

Here's one that I'm working on right now getting its bias tape crack-stoppers. The hide glue is getting brushed on prior to their coating of shellac. Before gluing on the lining, I sand them down a bit where they pass under the linings.



Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

I use cloth tape, installed under the linings, except on the flat area below the waist where I use a small timber support instead.
Without the arch in the rest of the rim, this area is more vulnurable.

All I know is that I've seen cracks go right past Martin tape more than once and never seen a crack stop because of tape on factory guitars. I assume better results can be had with tape depending on the method.

Didn't most of the old classical builders use wood?

By the way, I do think of them as braces. Just like with the other plates, it allows me to go thinner than I normally would and use the braces to stiffen it back up. Less weight that way which is a good thing in my book.

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I never said that.... Being the rebel that I am I will use anyone's method if it produces a better guitar. Martin does a lot of things right IMHO but some things not so right too.

For example, and forgive the digression here.... please... - Martin does not ream the bridge pin holes anymore. Check out the Martins at your favorite store and you will see the pins even on some pretty expensive Martins sit about 1/8" too high and more importantly there is a space between the pin and the bridge plate. Nearly 1/2 the string ball can get into the gap and prematurely wear the bridge plate.

It's a lousy way to do things and probably resulted from a study in which Martin is banking on most of these guitars changing hands before the bridge plate needs repair under warranty....

So no Tom my friend if Martin does it it does not mean that it's good enough for me. But OTOH I have the utmost respect for Martin too.

I use tapes.... 100% polyester Twill tape. I glue it down with 5 minute epoxy and glue the linings over it. It's not a very traditional approach but polyester tape is really strong and it glues well with epoxy. I tried a bunch of other things and this combo worked best for me.

Mark

http://www.blanchardguitars.com
http://www.guitarmakerdirect.com

I'm going to quit reaming my bridge pin holes

Seriously though, I've used wood and tape and like them both. Tape is much quicker because you don't have to spend as much time fitting them up as you would with wood. However I like the look of wood probably a little more. I haven't had any of my guitars around long enough to see a crack in the sides stop or not stop at either of these so no opinion there.

I will say that if someone can produce a photo of a crack that went past the tape and no photos of a crack going past wood, I would be inclined to switch to using only wood. But until then....I'm going to use which ever one I decide to use at the time.

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Hesh: I couldn't resist the jab in the ribs. In another forum I see that a lot and I also admire Martins but I just feel evil today.As Billy Joe Shaver said " The devil made me do it the first time. The second time I did it on my own".
Tom

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A person who has never made a mistake has never made anything!!!

What Todd Stock said was basically correct. The testing I did compared nylon twill tape to cotton-poly bias tape on several species of side wood at a 'normal' 2mm thickness. I used both HHG and Titebond, with shellac over the top, and made up a rig that allowed me to measure how much force it took to break a sample of side wood of a given size with the tape on the outside of the bend (as if you were pushing inward on a side with a tape on it). The best combination I tested was bias tape with HHG: the nylon didn't stick very well, and came unglued before it broke, and the Titebonded strips also had more of a tendancy to come unglued. It took roughly twice as much force to break any of my samples with tape as it did to break the bare control samples cut from the same pieces of wood. When the tapes broke, they broke on the crack, so it might seem after the fact that they didn't do much, but, as I say, it took twice as much force to break the taped samples.

I have seen tapes stop a crack, more than once. I have recently seen sides that cracked right across wood fillets without breaking them. In those cases the guitars were imports, and the cracking may have been caused by lower humidity here than where they were built. If that's so it's possible that the fillets may have been the cause, since they would keep the side from shrinking at that point.

Nothing is going to totally stop sides from cracking. Proper tapes can help a lot, though.

The adhesive tape that Martin used up from about the 60s (and may still be using), is not the right sort of stuff. It has a thick, latex sort of adhesive layer that allows the sides to move relative to the tape, so the sides can crack. I used to repair a new side crack for one performer every time he got back off the road. I finally got tired of it, removed the sticky tapes (a messy job!), and put in linen cloth tapes. That worked. I lost a nice steady repair gig, but that sort of work I don't appreciate, and the customer was happy.

Thanks for all the info folks! Yer a good bunch.

The old classical builders were often poor and used whatever they had. Sometimes they used unmatched tops,tops of more than 2 pieces,etc. if they had wood on hand,they used wood for the strips.

I can't say I've ever seen an old classical guitar with wood fillets on the sides, or tapes, for that matter. Strad used linen strips to reinforce the sides of 'cellos, and to line the sides of his inlaid fiddles, though, so it's an old technique.

Stupid Question Time!!!!!

Where does one get bias tape?

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

Fabric stores, I think I got mine at Michaels.

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Steve Smith
"Music is what feelings sound like"