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Wood caps generally fail because they are too short to provide adequate gluing area on each side of the joint.
Cloth caps, unless they come unglued, are generally flexible enough, especially if wrinkled to move with the joint. Whether this actually re establishes any structural continuity over the joint is questionable.

Whether you want the X intersection to be more or less flexible is another question.
This area often fails by splitting of the member with the open notch. I would consider a proper wood cap to provide some protection.

I complained to Stewmac about a month ago about this very thing. I ended up capping mine with a strip of spruce.

Al

The problem isnt with the cloth lap but the preshaped brace. It is a poor joint compared to shaping after the joint is glued together. It is my belief that a wood capped X is more stiff than it needs to be. Cloth would give a little and provide a more responsive guitar.

John, itswednesday pretty much nailed what I'm worried about. I'm not averse to using a cloth cap instead of a wooden one, especially after hearing your opinion on the matter. You've made what, 300+ guitars to my none? When somebody with your experience weighs in, I listen. I just really feel like that's a lot of open space in the joint. Am I making this out to be a much bigger problem than it actually is? Will a cloth patch over that gap make it that much stronger?

I've spent the last two days looking at every picture of guitar bracing I can find, and so far the only ones I've seen with this gap are pictures of Stew-Mac guitars. It's obviously not a huge issue, or we would all know about it by now, but is it really the best way to go? Would you send one of your guitars out the door with this joint?

I really hope I'm not coming across as disrespectful, because that's the last thing I'm trying to do. I plan on building many more guitars after this one, and I honestly just want to start out learning to do things the right way. I'm looking forward to diving a little deeper into your thoughts on the matter.

The way the string loading works on that area, the open face is under tension.

In timber engineering a glued joint of end grain to side grain would be considered to have no tensile strength (ie the same as having a gap there) It might have some but that is a bonus rather than an expectation.

So the gap is not a huge problem except aesthetically and I could never bring myself to build it like that
Fill it with glued wedges and it will be just as strong as one glued without gaps ie not very

I prefer to bridge it with a wood cap, john likes the linen take your pick either will work.

"It is my belief that a wood capped X is more stiff than it needs to be. Cloth would give a little and provide a more responsive guitar."

Hi John Smith,
I have heard others say this. Why do you feel this is so? (honest question - looking to improve my education)
Like many here I strive to keep the X joint tight and stiff and usually do the wood cap thing. I know Gibson has done butt joints on some X braces and they seem to have worked O.K.. Perhaps we are overbuilding things.
Many of the old ladder braced "parlor" guitars have folded up in this area when subjected to steel stringing. X braced Martins, although originally intended for gut strings have faired better in this regard. I think X bracing puts the strength where it is needed without adding too much weight. But how do we know when enough is enough?

I'm really surprised Stew Mac makes braces like this. I bought a set of pre-shaped braces about ten years ago and it was unshaped at the x joint.

I would love to see a picture . In 15 years I have yet to see a cloth patch fail.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

You probably just didn't notice. The cloth flexes and moves with the brace, quite often, and obscures the view of the brace being detached.

Seriously, those things fail quite frequently, I'm actually shocked you've never seen one!

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Old growth, shmold growth!

I do check and never seen one though I am more used to working on Martins. I have seen many wood caps fail Simon Patrick seem to be the worse for coming off.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it