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I'm getting ready to brace the top on my Stew-Mac kit, and I just notched the X braces. I plan on using a wooden cap across the X, and I'm not comfortable with the amount of open space left due to the pre-shaped braces.



How would you go about capping this? My initial thought is to use a finger plane to take a little bit off the top of the lower X brace, giving me a bit more gluing surface for the cap, and notch the cap into the other X brace where they cross. Will this work? Or am I just creating a bigger problem for myself?

Hello,

Why do they carve the bracing like this? This is no tight joint at all..
The solution would be using linen soaked in glue and put it over the X, but actually I wouldn't leave a joint like this, there might be an issue later!

How tall (& wide) are they at the intersection, Zac?


Ken Jones
Mountain Song Guitars

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Mountain Song Guitars www.mountainsongguitars.com

I wood have to replace those with some of my own.

Ken, they're 9/32" tall and 5/16" wide at the intersection. The joint is very tight where they meet, I just feel like that's a whole lot of open space up top.

The StewMac plans call for a linen cap, but I'd like to use a wooden cap to really lock everything in nice and tight. In the video that came with the kit, this looks pretty much like the joint they end up with after notching the X.

FWIW, I have some excellent red spruce brace stock that I bought from the Hampton brothers. If this ends up being something the majority of you wouldn't use, I'll try my hand at carving my own. I've been waiting to brace this guitar for quite some time, and it will be frustrating to have to postpone this step yet again, but I would rather do it right and have the best guitar I'm capable of building than compromise on something as important as this.

Or you could come down and spend a couple of hours cutting up a big pile of brace stock. Be home by dinner time with enough braces for five guitars...


Ken Jones
Mountain Song Guitars

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Mountain Song Guitars www.mountainsongguitars.com

Easy to do on your table saw

I personally prefer a wooden cap to the linen, but plenty of Martins have been built with just the linen.
I'd just cut wedges to fill the gaps then flatten the area just enough to install the cap at 1/4" width.
Don't make it too short 2" is good, you need enough glue area on each side

Are the stewmac braces tapered at the X brace joint? That just does not seem correct, it would make a very weak joint. The braces should stay square at the location of the joint. ... I guess they are, looked at their instructions.

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http://www.Harvestmoonguitars.com

I would never use this x brace on a guitar. That joint reduces the stiffness of the top in that area significantly. I would toss those and make your own. It's only the most important structural component of the guitar. I am really surprised that Stew-Mac would send these out.


Richard

Although not the best, those braces when capped will be reasonably strong. Some of the old Gibsons had X braces where one side of the X just butted to the other leg of the X - no joint to speak of. I would fill the gap, flatten the top a bit and glue a wood cap on it as Jeff mentioned. It will be stronger than what many manufacturers do.

actually the cloth cap really helps this joint. I never saw a cloth cap fail though I saw many wood one fail. this is designed for the cloth , it is designed after the martin style

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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

I've made lots of guitars like that and none of them have failed, to my knowledge. As well as hundreds of thousands of Martins. I don't do it like that anymore, but I think you're fine to go ahead. I always capped it with canvas saturated in wood glue.

Me either and the ones that I have seen that have failed should have failed when some 300 lb person flops down on top of the guitar in a drunken stupor....

Here's some food for thought - It just could be that the x intersection can be over braced, imagine that, and that the intended function of the X-brace intersection linen patch is to permit some, a limited amount of structural support but also permit a bit of flex in this region so that the top can pump and move a bit more freely.

Of course I've never dug up CF the first and asked him or whom ever originated the cloth patch idea but my suspicion is that the cloth patch is not a quick fix or less than as strong as it might be solution but instead an engineered effort to produce a more responsive instrument.

There is a tendency in my opinion for folks who have lots of experience with wood working to be very keen to make perfect joints, build things as rigid and strong as possible, etc. This is all good and my hats off to ya. But it also just could be that in the world of responsive acoustic guitars, other stringed instruments too, top movement is both desirable to a point and in a certain manner and something to be controlled but never eliminated completely.

I've always capped my X intersection but was curious about the linen patch especially after seeing as many as I do now, as often as I do, with nary a failure that would not be considered understandable under the circumstances of abuse.

After all we are not building ottomans here....

Oh, good. Now you've opened a can or worms...
Always thought X bracing was an over reaction to ladder bracing myself...

The joint would also be supported by a bridge plate and a bridge


Sent from my iPhone using Tapatalk

Hesh, my new La-Z-Boy model might refute your statement. Nothing sounds like old growth naugahyde.

I guess the brace that is open at the top is also supported by the other X brace that does have a proper joint.

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http://www.Harvestmoonguitars.com

True Barry my friend but now we have to worry about nauga being listed on CITES....

Yeah there is that too....

We see lots of ladder braced guitars since there are lots of collectors in our market and I love the sound of a decent ladder braced instrument. It's different and in it's own way a very cool tone IMHO!

that looks terrible -i'd make new ones.

i notch on a mill, glue together and then glue on a cap. next i radius in a dish, glue to top, then carve to spec.

Lots to think about here...I've looked inside a few of the guitars that I own with the linen cap across the X, but the braces are squared off at the X. None of them have a gap like this at the top. The joint on my X brace IS very tight...but I have to wonder, with the height of the brace being halved where they meet, how much strength I'll be losing with all that open space there, even with a linen cap over the top. I'm leaning towards carving my own X braces, but I also lack a reliable way to radius them at this point.

Ken, I may just take you up on your offer and ride down to hang out for a day...had a ton of fun when we were down there a few weeks ago, I'd love a reason to come back. I'm pretty busy the next two weeks but should have a little down time after that...gives me time to pick up a little more bracewood from Matt & Nathan anyway. PM me & we'll discuss it further.

As always, thanks everyone for your opinions...I learn something every time I post a question here, and I appreciate ya'll taking the time to share your knowledge.

The braces are not joists or beams but instead a brace. The joint is not going to kill or make the guitar. I hate to see a wood patch here as they tend to fail . You are certainly oped to do what ever works. Me I use the typical Martin design it works for me and almost 1 1/2 million martins out there.
The first known example of an X braced guitar is attributed to CF Martin and is dated 1843. Also a cloth patch and still firm.

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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

I've seen PLENTY of cloth caps fail.

Then, to fix it, the cloth and the glue have to be cleaned and scraped off.

Not a good for this guitar in my opinion, especially with those huge gaps.

Wood is the way to go in this case.

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Old growth, shmold growth!

It easy to radius bracing with a block plane.