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Top is Sitka, about .115" thick. Bracing is Sitka. Bridge plate is osage orange. The X braces are 5/8" tall at the intersection. All the braces are more or less triangular.
The body shape is OM.


Any input would be greatly appreciated.













Thanks,
Phillip

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Regards,
Phillip Patton

http://www.pattonblades.com

The bitterness of poor quality lingers long after the sweetness of low price has faded.

https://hoosierbladesmith.wordpress.com

Phillip: The shaping and scalloping looks OK to me for the figures you gave. I would just cap the X brace and clean up the work with some sanding. Having said that I am curious if you are following a plan...? The X brace seems to be back somewhat further then what I would expect,resulting in a short bridge patch and no doubt capturing quite a big chunk of the bridge.I build mostly dreads and a shape and size similar to an OM,but don't follow an official OM plan. Let's get some more input from other folks.Good luck.
Tom

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A person who has never made a mistake has never made anything!!!

i'm not really very experienced in the bracing dept., yet, but my gut tells me you should taper the upper x a lot more, maybe take the humps down a bit on the lower x, shave your fingers to about 1/4" high, and next time use 1/8" x 5/8" sticks around the soundhole. don't do it, yet, let's see what somebody that knows what they're talking about says!

That's my opinion as well.
The main bracing looks good. (I'm not a big fan of the extra-large scallop style. Yours keep a decent amount of stiffness all along the braces.) You could cut down the soundhole braces and the finger braces a bit by rounding the tops but they're probably OK as-is.
BTW, I'd be careful about using ink to mark your soundboard, as you can get bleeding. (Don't 'seal' the inside of that board!)
I stick with (graphite) pencil for marking and signing the underside of the soundboard.
John

Any of the braces that get tucked will have to be lower at the end, which will change the shape of the final inch or so. You probably know that.

Nice work. There are better experts than I, but here's my understanding, much of which you may already know --
- 0.115" is on the thick side for a sitka OM top (unless it's pretty floppy sitka), as is 5/8" for the X-intersection (9/16" seems to be more common). The combo of the two, and the non-forward-shifted X, would probably make for a fairly stiff top.
- As above, both ends of the Xs could be feathered thinner where they meet the kerfing. The lower X tips are often feathered to nothing, like your other braces.
- The upper legs of the Xs could be tapered more in height, but many good guitars aren't.
- The X-scallops look good.
- A cross-section with a pointed top isn't so good for strength, as it puts a small amount of wood in the highest stress state. But it seems to work.
- Capping the X-joint is a good idea (e.g., a 1/32" strip), but lots of good guitars aren't capped if the joint is made well.
- At least one of the lower front braces is usually scalloped if using scalloped Xs, but I build like you do and it seems to work fine.
- Your ~tall soundhole braces are generally consistent with Somogyi's advice.

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David Malicky

The sound hole bracing is over done . All you need is something to help support the areas under the rosette. Don't use a wooden plate but do use a cotton patch over the joint. In all my years of repair , I never seen a cloth patch joint fail . I can't say that about the wooden patches.
You scalloping is plenty , so the only other critique is to break all sharp corners. Making bracing too light can be worse than making them too heavy .

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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

IMO your soundhole bracing is fine. I would cut all the bracing down lower where it butts to another brace, and lower the lower face diagonals (the "tone bars")

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Hi Guys,
Thanks for your suggestions. I implemented most of them.

I'm making this guitar from the OM plans that LMI sells. The plans call for much beefier bracing; I slimmed it all down quite a bit....

The last steel string I built was over braced, and I had to go in and shave the braces after the fact, which was not fun. So I shaped these based on how that one ended up, taking into account differences in material stiffness (I hope).

I'm hoping to sell this one, so I want it to sound great. Thanks for all your help. Now I don't feel like I'm shooting in the dark quite so much.

Phillip

_________________
Regards,
Phillip Patton

http://www.pattonblades.com

The bitterness of poor quality lingers long after the sweetness of low price has faded.

https://hoosierbladesmith.wordpress.com