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Mike, that is pretty much exactly as I do it.

You may want to look into getting some of those little acid brushes, quite inexpensive and have pretty stiff bristles and work great for pushing a patch down into the corners. They are great for HHG also since you can just throw them out. When I was in the body shop I used them for cleaning my spray guns and body men used them for fiberglass work to get the mat into tight corners.

http://www.amazon.com/Acid-Brushes-144-box/dp/B002HEUFUW/ref=pd_sim_sbs_auto_4/176-3572168-4928308?ie=UTF8&refRID=14R3HR9JVXYA9SAVA72X

I tried the Harbor Freight ones which are much cheaper but they loose their bristles. But even to get good ones don't cost much money.



Not if you are careful and don't go crazy with putting too much glue on. I put the patch on and when it is all stuck down into the corners I let it dry for a little bit and then give it another coat.

Cheers,
Bob

It's all about the technique. I don't want a mess anywhere inside the box. I think u will find that any resulting excess is easily cleaned up. Maybe u will alternate between cleanup and readjusting the fit. I do. It eventually just works out. My little cheap Walmart paintbrushes do the trick.

Just don't use ur fingers

my notion, I thought it might be a little stronger and the x members could then be a bit "more flexible". I used a touch of epoxy in each corner to make a sort of webbing, too.
The cloth can be seen in old furniture, too. I have seen it used to reinforce the intersection of thin glass mullions on old case furniture.
I have not finished this guitar, so I can't comment on its success. But its probably been done many times before, and somebody else already knows if its a sucess or failure.

Gotta cap it !

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I'll post a pic of one of mine soon

The point of the cap or patch is to keep the open side of the box joint closed. If it's allowed to open up, as it will from the down pressure of bridge torque, it concentrates the stress at the bottom of the cut, and the brace can split. I've seen this too many times in old (and not so old) guitars. As Bismark said: "Any fool can learn from his mistakes; a wise man learns from the mistakes of others" Let's learn something from those failed guitars.

I think it's Somogyi who calls that little spruce cap the most important couple of grams of wood in the guitar.

Steve

I started taking a slightly different approach awhile ago. I had used the cloth patch and just didn't like the asthetics and for some reason didn't like the solid thick cap. So at the time I needed to cap tge X I looked down at the floor and noticed a lot of full width plane shavings I just made in trimming the braces, so it glued about 5 or 6 of these to the top of the X (one across one brace the next on the other... So they crisscross and form a "plywood" type laminate over the gap). When the glue dries you just sand it down to get a nice smooth look so you hardly notice the cap.

I don't know what downsides ther are to doing it this way, but to my mind it should fall in between the cloth and the solid cap in stiffness but but much less conspicuous than either of the other two options.

Kent

I had a 1970 Yamaha dread in the shop this weekend. The X brace was not notched but instead one side of the X was long and the other side of the X was two pieces that were butted up against the long brace. (wish I had a pic). No cap. It has held up well over the years. The top was .115-.120" thick and the braces were quite thin. Sounded pretty good after a refret and set up.

I cap my bouzoukis (floating bridge - lots of downward force), and patch my guitars with linen like Martin used to do it. It is quite amazing how strong those patches become when soaked with Titebond.

I believe it was Gibson that did the same on some x braces and had less luck than that Yamaha did.


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I'm sure I read here on the forum that a cap of minimal thickness serves the intended purpose more than adequately. After all, when you think about it, the value of the cap itself lies in its strength in compression. I tend to think that a thin layer of any fairly dense hardwood should do the trick. Comments?

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Cheers
Pete

I think the cap is in tension and I agree it doesn't need to be very thick, maybe 0.040" to 0.060".

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Steve Smith
"Music is what feelings sound like"

The cap is in tension indeed: its holding the open side of the joint closed. The cap only has to be thick enough not to be pulled apart. What's more important is the area and length of the glue line between the cap and the brace on either side of the joint.

I have to be the outlier, it is my calling in life.
Who of you who do repairs as I do, have seen cracked X-braces at the joint, on any but the cheapest, poorly glued guitars, and then only as a result of a major impact?
Did you know that Gibson, all thru the "Golden Age" on many guitars like the L-00, used a butted-X-joint, where one brace is solid, and the other 2 pieces, and a tiny bit of cloth at the cross?
Very rarely is a well-glued X-joint under any particular danger of over-stress. From what I see, most X-braces are over-built.
It is no trouble to add a sliver of wood if it helps you sleep at night.
How ever you build your bracing, be sure to recommend to the owner not to sit on the top.
Disclosure: I sometimes glue a bit of cloth.

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"Who of you who do repairs as I do, have seen cracked X-braces at the joint, on any but the cheapest, poorly glued guitars, and then only as a result of a major impact?"

I already mentioned a Taylor with a cracked brace. There was no evidence of impact, and the owner said there had been none.

I've seen those old Gibsons with the braces peeling off the tops, too.

Sure, it may be a rare one that has a problem, but both theory and practice say that it's a spot where you'd expect problems. In that case, what does it hurt to reinforce the joint? If you think it's over built, then reduce the size of the bracing, but reinforce it, since it will be that much more likely to have a problem.

That's the issue, isn't it? Repair people usually only see the ones that fail; they seldom see the ones that don't, unless they happen to notice that construction while repairing something else.

I think I'm going to continue adding that little bit of linen, though. It's cheap insurance, and I know in my heart of hearts that my builds will not always get the tender loving treatment they deserve. They are meant to exist in the Real World, with all its bumps and drops and scrapes, and I feel that it's no trouble to add that little bit of work.

Hey Al, I'm currently reading about you in "Guitar Makers" by Kathryn Marie Dudley.

Interesting stuff. But I'm not sure the social sciences are the best prism through which to view lutherie.

On the other hand, I've been wrong before

Steve

Has anyone actually measured an increase in stiffness or resonant frequency by capping the x? I did some tests years ago and found the effect to be negligible. I see a lot of people use a cap (I don't), and I understand the theory, but you should be able to measure an increase in stiffness if the cap actually does anything

Steve wrote:
"I'm not sure the social sciences are the best prism through which to view lutherie."

I tend to agree, and I got my BA in Sociology! I'm currently re-reading the book and taking notes this time, to try to address some of the things that she seemed to have trouble understanding.

uvh sam asked:
"Has anyone actually measured an increase in stiffness or resonant frequency by capping the x?"

I've seen a change in the shapes of the 'free' plate modes: they tend to be more symmetric when the brace is capped. It's been a while since I looked at that, and there may be (probably is) a rise in the 'free' plate mode frequencies as well. This may not translate directly into a rise in the frequencies of the modes on the assembled guitar, but I'm pretty well convinced that the 'free' mode shapesa re at least as important as their pitches, so in that sense as well the cap is worth it.