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You ever get that sinking feeling like you've really gone too far this time? That's how I feel right now. But it's right on the line, so before I peel all these wonderful braces off and try again, I figure I might as well put the spectacle on display and make sure you guys agree.

The only real problem here is the height of the X legs between the bridge and the X intersection. UTB may be tapered a bit excessively as well, but I'd be willing to chance it given the C shaped headblock that will be butted to it and supported by the back's UTB as well.

Anyway, the top is about .110-.115" thick, 15.25" lower bout width (small dread shape), X braces are 5/16" wide, about 9/16" high at the intersection (not including cap), tapering quickly to 1/2", and on down to 7/16" at the upper finger braces (about where the bridge wings cross it), and triangular cross section. It is a rather wide angled X. About 1.25" between the front edge of the bridge and the X intersection. Top is domed using Cumpiano style arched braces sprung to the plate. X braces are arched to 1/8" offset (approximates 28" radius, I think).

Tap is great, flex feels about right. Just a bit stiffer than my retop test guitar, which has been strung up for over a week now and sounds great. That one has a bit of a belly, but hasn't changed since the second day. The X on it is about the same height at the intersection, but only very slightly tapered by the time it reaches the bridge wings, and 90 degree spread.
So while the flex on this one's lower bout overall feels good, I worry that the small area in front of the bridge should be tighter. It's kind of hard to judge stiffness by flexing over such a short distance and where it's hard to get a good grip on it, so I'm mostly going on visual and imagination based on flexing the full length of each X leg. Flexing across with my thumbs on the upper legs of the X feels quite stiff though.

So... redo, or risk a retop? I could even try to remove just the X without damaging any of the others, but I wouldn't be too disappointed to redo completely, as I would kind of like to thin the top a bit more (.100+-) and try taller bracing. But then thinning would involve removing the bridge plate, which I suspect will be a bigger pain than chiseling away spruce braces.

I think its fine, but I only have 3 guitars under my belt. However, I scalloped down to .25" on the lower legs of the X-brace. Your tapered braces have much more meat in the same area.

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PMoMC

I don't have enough in the bag to give my opinion any validity, but I'm bumping this because I like seeing what others have to say.

Relative to the guitars I build, you are heavier duty than any of mine. I'm still trying to build one light enough that it fails. I haven't got there yet. My finger braces are a lot lower. All my braces taper much more gradually on both ends. My x-braces taper to nothing before the lining in the lower bout. My braces are generally a hair wider than yours and I scallop them.

I'm not sure what you're asking about the area above the bridge. Isn't that the intersection of the X? It looks like it's capped? That's got to be the toughest area south of the UTB.

Oh yeah. And the standard disclaimers apply: every piece of wood is different, different building styles, players, strings, YMMV.

Mike

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Mike Lindstrom

Glue it on, and slap some strings on it.

I am Bumping this thread as well , Since I am about to start bracing My First " Guitar" top I want more input as well . What I see "Looks" good . However I only know Mandola and Mandolin Bracing

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What caught my eye is the spread of the x-braces. It's pretty wide by most standards, unless the top has low cross-grain stiffness. As for height, they're a bit higher than I use, but not drastically so, though I put more taper on. I tuck all the ends of my x-braces.

None of this is cast in stone, though.

My .02.

Pat

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

What caught my eye is the spread of the x-braces. It's pretty wide by most standards, unless the top has low cross-grain stiffness. As for height, they're a bit higher than I use, but not drastically so, though I put more taper on. I tuck all the ends of my x-braces.

None of this is cast in stone, though.

My .02.

Pat

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

Try it out and let us know! I always get a kick out of these "look at my braced top pic" threads - I voice mainly by ear and can't imagine just looking at a picture being able to judge someone else's work...

If I string a guitar up and it develops multiple "ripples" (i.e. some minor buckling) in the first few days then I think that is a bad sign. The guitars I've seen built like this exhibit buckling up towards the lower half of the sound hole. I think this is bad omen for the life of the instrument.

If, however, you string it up and you just get a little belly in front of the bridge and a little bit of pull up behind, then I think that is OK. Your mileage may vary....but this is what I've worked out for my stuff.

Very interesting topic and I think it is one in which we all develop our own approaches & tactics to building an instrument "just right".

Best,
Trev

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http://www.PeakeGuitars.com

That's the reason I don't usually comment in the "look at this bracing" threads.
...........however, to me it looks like alot of room between the upper legs of the "X" and the upper face brace. Does it look that way to anyone else?

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All from looks of course, but the size of the braces look fine.

Your X-Brace angle looks really wide. You want the x-brace to go under the wings of the bridge to lend some support as well as where they are placed in relationship to the bridge (as in how much of the bridge is over the braces) makes a considerable difference in tone.

So long as your bridge wings hit the X-Brace I'd say you're totally fine.

As for the lower face braces I like how they are positioned. Spread out better. I've found myself gravitating towards patterns that spread themselves over the top so there are not large portions of unbraced sections, or tight clusters of braces.

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John Mayes
http://www.mayesluthier.com

Based on what you have said and the photos, I don't think you have any problem.

Couple of observations: Don't use curly maple for a bridge plate. It is weaker and more flexible, and worst of all, it chips easily. I would replace it while you still can do it easily.

Don't measure the spread of the X by its distance from the bridge. I see people giving this distance all the time. Even more often, they give the distance from the soundhole to the X, which IMO is meaningless. I couldn't tell you what it is on any of my guitars. I treat it as just an artifact of the other design parameters. Where do the X arms cross the bridge wings? That matters. I generally don't like the X arms to fall wider than where the inner edges of the X arms intersect the lower corners of the bridge. I have gone wider with good results, but I think that's not a good idea for an inexperienced builder.

If you are worried about dipping in front of the bridge, put a small transverse brace between the X arms in between the bridge plate and the X. It's not a very active area; this won't hurt the tone. This guitar does not need it, though.

Last, I like a longer taper from the diagonals and finger braces to the X.

And I would not thin the top, knowing nothing about it other than its current thickness.
Now you have most of my secrets. :->

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Just for the record, keep in mind that there are other variables than bracing/top thickness that will affect the degree of deformation to the top, such as string pull (of course), string height above the top, and (to some extent) size/shape of the bridge footprint. You might consider changing any of these. If, for example, you reduce string height above the top (at the saddle) by 20%, the bridge will exert 20% less torque on the top. However, judging from the comments from experienced people here, it sounds like you should be fine if you leave it as is.

Thanks to everyone who has replied! I'll keep tapping and flexing and staring at it, but definitely feeling more confident in it now.

Oh, and I forgot to mention this is a 24.75" scale, so with lights, it should be even less likely to fail.

And to answer a few questions/points...

Oddly enough, that piece of curly maple is what I got when I ordered a rock maple bridge plate from LMI. I thought about saving it for inlay and using something else here, but it feels plenty stiff and solid so I decided what the heck. I doubt I could get it unglued without messing up the glue on the braces around it and separating the center seam, and trying to chisel it out would likely result in a hole through the top, so I think I'll leave it. But thanks for the point, Howard I'll stick to straight grain from now on.

The X is indeed wide, and even a bit wider than intended. My first guitar was a wide X (Gibson Hummingbird pattern), and I wanted to try pushing it a bit wider on this, and then narrow to 90 degrees on retop test to get a feel for what difference that makes.

The long distance from upper X arms to upper face brace is due to the wide angle and shifting it down so the bridge wings can reach the lower legs. I have contemplated adding little braces parallel to the soundhole braces, similar to how there are two fingers in the side quadrants. But I think it will be fine as it is.

The bridge wings do make a good connection to the X, but not quite as much as normal, given that the X legs spread away from it so quickly below the front edge. Also connects firmly to tone bar 1, which I have been up in the air about carving back to the edge of the bridge plate or so. I did on retop test, but this one is putting more responsibility on the tone bars for the long-grain stiffness, so I thought better to leave it firmly connected. Tone bar 2 could definitely be scooped back safely... not sure what effect that would have on tone, so I just left it similar to the other one

And the reason for all the measurements is because I can't communicate how it feels, and didn't do any measured deflection testing. Also to give as much reference as possible for visualizing the scale of everything. The idea to thin the top to .100 if I was going to rebrace is based on how it felt before this bracing, not just numbers off a plan kind of thing. But I'll save that experimence for next time.

Do you know what the angle of the X is?

Just curious.

Kevin Looker

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I'm just a guy who builds guitars in his basement.
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You have a very good luthier giving you good advice so you might want to pay attention. You can chisel and plane the bridge plate off......I did the same thing at the same stage after Mario gave me feedback that the fit to one of the X-Brace legs wasn't good enough. And remember that where 2 braces meet (like the tone bars intersecting the X-brace leg) it really stiffens that area. You are getting some structural benefit from the upper tone bar but the lower tone bar isn't as important stucturally and is in prime, sound producing real estate.........just sayin.

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Formerly known as Adaboy.......

I also agree with Howard in regard to the bridge plate. If you have, or have access to an artist's pallet knife, and a heat gun, this is the easiest way to remove the bridge plate without damage to the top and surrounding braces. Simply heat the palette knife with the heat gun and work it slowly and carefully under the bridge plate. You may have to do this in several attempts melting the glue a little at a time and before you know it, presto, the plate is off. Ultimately, it's your call, but I wouldn't leave a flamed maple plate there if it were me considering all the other hard work that goes into the guitar before and after closing the boat.

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Bill Hodge


One does not simply, own enough guitars!

If you're concerned about the flamed maple bridgeplate chipping, just add a small, thin rosewood plate where the pins will be. I think the tonebars could be tapered more and have a gentle scallop.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Aside from the bridge plate change which you might seriously consider, there isn't anything looks like it's doomed to fail here. The rest of the comments really are more peoples personal preference (myself included). I say just finish building the dang thing and see how you like it. It'll at least give you a frame of reference to build further upon. We can sit here and analyze, and debate someone elses bracing forever, but at some point ya gotta put the dang thing together and see how you like it.

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John Mayes
http://www.mayesluthier.com

Alrighty, did another round of shaving, taking the suggestion to loosen the connections to the X brace a bit (personal preference, yes, but I think it was a good idea). I didn't take too much off the upper tone bar where it connects to the bridge, but that spot is definitely tight sounding compared to the rest of the area, and is better now than it was. Tapering the fingers more was a good idea as well, I think. Particularly the uppers, which may have restricted the bridge too much as they were. This puts the bridge corners at about the middle of the tapers, so it should have some flex there now, but still some support too.

Excellent idea, Ken, with the small pin plate. I'll do that. Much less scary than removing the whole bridge plate and trying to fit and glue another one precisely (much easier when the soundboard is still flat!)

And about over-analyzing... you have found my weak spot, John. I can't stand to "just put it together". It must be theoretically PERFECT If pondering on it for a couple days before making my move gives me a significant improvement of sound compared to just winging it based on plans/photos I've seen, then I've saved all the trouble of constructing another whole guitar to make that step of knowledge 'course, there's the actual physical construction part that I need more practice at too... it's a double-edged sword, but it's my nature. I think it's time to start closing this baby up though, as soon as I get that pin patch in there

But how do you know if what you did actually gave you a "significant improvement of sound" ? How do you know if what you did didn't actually take you further away from that? Sometimes you can only make that "step of knowledge" by doing because you'll never know what that guitar would have sounded like if you had left it the way it was to begin with. I'm not saying what you did was bad, or good. It is what it is.

There really is only one way to gain true experience.

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John Mayes
http://www.mayesluthier.com

Nobody but you knows how the top sounds when tapped, how stiff or floppy in both directions it was before bracing or even how thick it is. However, visual cues are something and I would venture to say that the finger braces look tall to me and that along with the tonebars you would gain tremendously by substantially lengthening their tapers or scoops. The bridgeplate also looks a bit thick, although you could feather it out in the back. I would replace it with either rift or flat sawn non figured maple or a light hardwood.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

John Mayes: So true,so true. We start with wood that has a certain potential and the BEST we can do is to NOT lose that potential. Hard work and takes time and experience.
Tom

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