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I know it's difficult to judge bracing without being able to tap/flex/glitter ect. yourself, but have a look at my braces if you have a moment.
They are rough carved. I will post some dimensions and weights in a few minutes. The guitar is a Kinkead OM. Mostly I want to know if they raise any warning flags for you. The only thing I am considering doing is bringing down the bottom tone bar a bit. Also they look a bit like a beaver chewed them at this point, so I will clean them/smooth them up a bit.

The top is .110" thick and I'm thinking it is about average stiffness and a bit denser than average. The x braces are 9/32" thick and the finger braces/tone bars are 1/4". The x braces are a .520 tall at the x junction (not counting the cap). The highest part of the scallop on the x is about .510. Lowest part of scallop on x is .39". Highest point on tone bars is .49". Lowest part of tone bar scallop is .275. I generally like a guitar with a bit of bass. One of the favorites I have played was a D35 (why I'm making an OM I don't know). Let me know if you want any more info! Thanks for your opinions.

Looks reasonable to me.

Your UTB looks very heavy to me. You could stand to pare it down some. In general the top looks to be a bit overbraced for an OM. From the look they could use thinning out. ( more triangular ).
Start tapping and carving. Begin with the utb.
My .02.

Cal

Edit. Finger braces also look heavy.

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Yeah, it's funny, the UTB is actually smaller than it calls for on my plan. I actually asked on the forum if it was ok to go the size I did and everyone said it was plenty large. In looking into it, I realized how much smaller (thinner) the UTB is on many plans, but I left it thick because I've read that the upper bout doesn't contribute as much to the sound. I'm constantly changing details of the Kinkead plans and I kind of feel bad sometimes, like I'm mixing methods and procedures like crazy.

Not sure what the Kinkead plans call for. The UMGF has a nice thread with hundreds of pics of different year Martin bracing might be worth a look.

" I left it thick because I've read that the upper bout doesn't contribute as much to the sound."

It won't hurt for it to be a little heavy. An experienced builder might know where he could go lighter with some of the braces, but I think the main thing for an "early" guitar is to make it structurally sound with a reasonable chance of sounding good. The more you build the more you will get a feel for how light or heavy things need to be. Going too light can make it a little tougher to set the neck if you don't know how much the top will "pull up" under string tension.

I've not seen really short LFB's like that before. I also question the tall 'node' on the lower LFB being right dead center. My understanding of scalloped brace design is to get the monopole 'air pump' loud speaker mode to be dominant, that's basically weaken the center of the lower bout under the bridge.

But who knows? It will probably come out sounding well and might even be fantastic.

Interesting. To be honest I didn't realize how much shorter they were than the typical pattern. I guess that means that the soundboard will automatically be more flexible right at the edge because there is no brace there at all. As mentioned in the original post I am thinking of taking the lower tone bar (LFB?) down some. I was just waiting in case someone said "EGADS, don't go any lower!" I get a nice tone from most parts of the top (to my ear), but maybe not so much right down there. I may block plane the corners of the UTB off a bit more. It'll still be massive, it may just be a bit lighter.

I have both the Kinkade and Antes OM plans as well as the StewMac 000 plans. I always thought it was interesting that Kinkade does not run his tone bars (braces D and E) all the way to the kerfing - they stop about an inch short. That certainly would free up the lower bout, maybe something like what Taylor is doing with their little edge route. I prefer to run the tone bars and finger braces all the way to the rim (but not tuck them) - I can't say why but that is what I'm used to seeing and it has been working fine.

The Kinkade bridge plate is larger than other plans show, his UTB is thicker and the two sound hole braces are also wider than some other plans. However, with all of that said, your top looks very much like the pictures in his book, if that works for him it will probably work for you too. Carry on.

I did shrink the bridge plate by quite a bit. His is pretty big

You should be fine. Remember a couple of fundimentles about beams (braces are structural beams) - strength and stiffness are proportional to the width, but are proportional to the height cubed. If you double the width you double the stiffness, if you double the height the stiffness goes up by 8X. Another way to think of that is that a small change in the width of a brace has a small change on the stiffness, but scalloping can dramatically change it.

I have an old Martin from the "over built" era that has had the large bridgeplate replaced by a smaller one and the braces scalloped (thru the sound hole). The results were dramatic - when I got it back from having the work done my wife's comment was "you are playing louder".

ps - you might want to read the currently running thread on braces

I took down both tone bars, took a little off the finger braces, contoured the utb a bit and sanded everything smooth. For posterity, here is a picture of the braces as they are going to be when the top is glued to the sides

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Go for it!

You may want to check the thickness of the ends of the UTB.

If you plan on tucking them into the lining, fine. If you plan on putting them through the sides, your binding will have to be pretty tall to cover it up...

Ed makes a really good point about the thickness of the ends of your UTB.

Otherwise, I think it looks good. If you wanted to loosen it up just a bit, I think you could afford to take a little off the sides of everything. Make everything more triangular.

But that’s just one opinion. I think you’re in the right ballpark.

Good luck

Steve

Yeah, I'm not cutting through the sides with the UTB. Or rather, I didn't (since I just finished doing it). Steve, I'm not sure how much pointier I can make those suckers! Maybe it doesn't come through in the pics. Or there is a realm of pointiness that I just can't fathom at this stage. I want to send a huge thank you to everyone who gave an opinion. I know it is kind of like wading into murky water. For now I am set on leaving them. There is always a chance for modification after it is attached to the sides, but just now I don't think I would feel comfortable with much more. Maybe if I can get an audience with a local builder....

Looks good to me. I wouldn’t change much.

I don’t tuck the lower X but do leave the ends long as well as the face braces and trim them just short of the linings when fitting the top. Usually have to reshape them a bit after that.

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I was just going to carve the lower x end almost to nothing after the top is glued to the sides.

your quadrants look nice and even. how does it tap out?

also consider that:
-binding will raise the pitch.
-finish will effect the pitch.
-kerfing type will effect the pitch.

Hi Arie, Do you mind explaining what you mean by "your quadrants look nice and even"? Not sure what that means! But thanks for the compliment I guess. How does it tap out? That's a really good question. I certainly spent a lot of time tapping on it. The best thing I could find to help me were the videos on top voicing by Dana Bourgois on Youtube. He emphasizes a few things: Flexibility across the top to balance out with lengthwise flexibility (which he claims is mostly set when the top is thicknessed), a rich musical tap, and more than anything he emphasizes a variety of different harmonics in different areas on the top. I think I got the flexibility about right, and I get a surprising deep musical tap depending on where I'm holding the top and where I'm tapping. I do get some variety of tones, but definitely not to the same degree as he does. All of this is kind of bonus learning for me though and I'll be pretty satisfied if my guitar is not totally overbuilt and tight sounding.

Probably just me but... I like to take a picture of a top and mark it up like this. After it is strung up and playing you will have a point of reference of what went right, or not.

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Joe Beaver
Maker of Sawdust

Hah! Good to see I'm not alone in doing that.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

the spacing between the tonebars. some people go for symmetry some don't. i'm of the school of a completely even tap tone across the top and having even "quadrants" helps with that. some people like Dana go for a variety of tonal "colors" across the top with different notes all over. that's ok too.