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I find that I have this habit of just going with my intuition when setting up braces for this guitar building thing and there is probably no cure for it. This is my second attempt at a Martin Jumbo kit and I can't say where this pattern appeared from and am hesitant to post in light of the remarkable couple of first timers that have posted.

As you can see my workmanship is not all that great and I wish the side braces were a bit more symentrical but I would like feedback in the form of warnings or other such cautions about the design before I button it up.

I did get a feeling for having the braces radiate off the bridge but other than that I just winged it. I also have this habit of posting to this great forum AFTER it's too late. So does it appear to be too light? Should I add anything? In the lower bout?

A pretty remarkable thing happened to the top while I was building it, as the top was as dead as I could imagine when unbraced and much different than my first Sitka top which had a pretty good tone, or least a tone that I could recognize as a tone.

After this top was braced and tapped, which I know nothing about tones so the braces were just free hand shaped then assembled, it now has a really great ring to it. Pretty cool but still no clue why or wherefore.

So without testing each brace for its deflection rate and not calculating the parabolic scallop rate of mode vibration, will this top be strong enough or am I heading for trouble down the road.

Thanks

Larry

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Your workmanship looks clean to me!

I think you have enough strength. I'm not an expert by any means but I really like the look of your design. I'd say it looks comparable to mine in strength. I'm just guessing as I don't know all your measurements.

Out of curiosity did you happen to weigh your top. I know a few guys have posted the weight of their tops and I am always interested to see how they compare.

What radius are you using on your top?

JoshJosh H38735.9239583333

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Josh House

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[QUOTE=Josh H] Your workmanship looks clean to me!

I think you have enough strength. I'm not an expert by any means but I really like the look of your design. I'd say it looks comparable to mine in strength. I'm just guessing as I don't know all your measurements.

Out of curiosity did you happen to weigh your top. I know a few guys have posted the weight of their tops and I am always interested to see how they compare.

Josh[/QUOTE]

Thanks for the reply Josh and to answer your last question, no, I didn't weigh the top as it wouldn't mean anything to me at this stage, I'll consider it next time if it will help others make design decisions.

My biggest concern was with the tone bars which normally run diagonally across the lower bout. There is MUCH less wood in the two new radial braces but it seems their new position would pick up more stress directly from behind the bridge which I assume is where most of the stress is.

I thought about a reinforcing diamond or two across the top joint as those tone bars do nothing now to keep that joint together, what do you think?

Thanks
Larry

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Hi Larry,
             Gee ! I hope I'm one of those first finished posters !
IMO your braces look plenty strong enough . You even used the A frame set up !
Looks to be very neat and clean work Larry. Very well done. Maybe others may disagree , but I'd say go with your instincts on your bracing plan. There are hundreds of variations out there , what's to say yours isn't the best ever built .I've got a feeling your going to have a very special instrument..

Kind regards, KiwiCraig

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CRAIG LAWRENCE of AUSTRALIA
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Same as Kiwi and everyone, looks stong enough well shaped. If you have a good feeling, go with it no matter what, we're here to learn so don't even be afraid of mistakes because they are also part of LEARNING! My 0.02 cents but there's a bunch of people that are in line to answer you on that, just wait and read

Serge

Larry, Not to worry, go with it. In some respects, this has similarities to what I do. I did a post a week or two ago (lost track of exactly when) on my bracing pattern. You can probably search somehow and find it. I probably would stick a diamond or two over the top joint below the bridge. That is what I do where there is the longest unsupported space. I also brace the upper end sort of like what you have done, but it is to accomodate my adjustable neck angle system. I will be posting more on this in a couple of weeks when I get my next build going. (After a week or so trip to the northern part of Manitoba - no, not a vaction )

Grant Goltz

[QUOTE=KiwiCraig]
Hi Larry,
               Gee ! I hope I'm one of those first finished posters ![/QUOTE]

Thanks for the reply Craig and YES you are one of those first time builders I was referring to. Seriously considering some kind of ban or maybe a review board that when someone posts such a beautiful first time instrument they are required to title the post "20th guitar". Very nice work again.
larry

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[QUOTE=Grant Goltz] I probably would stick a diamond or two over the top joint below the bridge. Grant Goltz[/QUOTE]

Thanks Grant - still considering some kind of small, shaped cross-grain brace across the top joint I'll post something if I go with it. Any other ideas?

Larry

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[QUOTE=LarryH]   Any other ideas?

Larry[/QUOTE]

Get on with it so we can listen Seriously, looks good.

Grant

Larry,

Dare to be different

The fan braces behind the bridge are, if I have interepreted his posts on the AG Forum correctly, what Rick Turner is currently doing on his acoustic guitars so you are in good company there. I have contemplated doing this on one of my guitars rather than the broken X I currently use.

One thing I might have done would be to put a brace behind the bridge plate that joins at the 2 legs of the X braces - I think I've seen it refered to here or elsewhere as the "Musser brace". This doesn't have to be very tall but might help give extra strength for the behind bridge area, as well as the tonal reasons (I think it helps string balance but as usually I could be totally off beam).

Your workmanship looks fine and the shaping looks really good. I always was worried about my bracing being not strong enough on my early guitars, but the more I build the lighter I go and yours look great. I'll bet that top really does ring out!!

Let us know how it turns out.Dave White38736.1150578704

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". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

   I see you are using the A frame X hybrid. I like the strength of the upper support though I feel there is more that than needed. remember that martin is designed for warrantee issues.
     What we think isn't what matters , it is what you hear. That is why we all build , as we are looking for the quest of the perfect guitar.
    As you go you will learn to quantify your placement and get more precise as to placement. Just using intuition isn't the best as you need to know where and why. You are in the ball bark of position. Start charting your tops . That is what I did in my early days so I could find what happens when things get moved around.
     Keep us posted as I am sure there are some of us with alot of interest in bracing. The parabolic braces are a nice modern touch.
john hall

Looks plenty strong enough to me, I think we all build our braces far too heavy as it is. The brace shape looks nice and smooth to me which is what I aim for. I like the idea of the fan braces behind the bridge (I'd would've used three), harks back to the days of the 18th century lutes and many of them are still holding up fine, in fact I restored one a while ago.

I like to see people ploughing their own furrow, if we don't innovate we stagnate. You get my vote.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks so much for taking the time to post your thoughts and ideas and the encouragement.

I'll probably go with my feelings again about strength and added brace positions, perhaps a small brace behind the X brace and in front of the bridge plate, and a small, smooth-shaped reinforcing brace across the top joint.

thanks again

Larry

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You know I think it's prbably going to sound like a guitar so I say go for it.

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Tickle your guitar daily, and it'll tickle you back.