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I've had a set of OLF SJ plans for quite some time & want to move forward on a build w/ them. Doing some research here & on the OLF, it seems the bracing pattern orig laid out by the architect (M Payne) comes into question, esp w/ respect to the X-brace & the tone bars being so apart from each other. Seeking a bit of advise here as to how one would go about rectifying the bracing layout.

In one Thread, I saw that Tippie had built an SJ & moved the bracing around more to his liking. Would this be, spreading the X-brace, so it's more open and so it is not so close to the 'upper transverse brace' ? Seems like the pattern for an OM w/ 1/4'' bracing would be the better way to go, since the dimensions (body widths) for the SJ & an OM are relatively close...?

edited to add pic...

I'm sure John will clarify what he did. I know that the x-brace can be forward or backward shifted, depending on what you aim to accomplish.

I had a project guitar that I replaced the top on, as well as the 00 that I just built. The project didn't conform to a OM or 00, but fell between. I spread the x-brace so that it fell ~ 1 1/2" from the bottom of the soundhole. In the case of the 00, I had a plan, but wanted to forward shift the brace towards the hole, to increase bass response. In this case, the ends of the x-brace would have overlapped the transverse brace, so I spread the brace to make it fit better and shifted it forward 1/2" so that it fell 1" from the bottom of the soundhole. The project guitar had a well rounded voice. The 00 has a rich, well rounded voice and has excellent bass response.

I didn't like the brace layout. I think it sounded too tight. I opened the X brace to 98 degrees. Moved the tone bars more into the martin position. That was more pleasing to my ear.

Thx J & D...

John,
Did you keep the center-point of the X-brace as in the plans or move it closer to the soundhole edge (fwd-shifted) ?

Since the body's slightly longer/lengthier than an OM, it has has more open acreage below the bridge locale. Seems it would not make sense moving the X-brace up 1" from the soundhole & have all that open space below bridge on the top. Plus, taking away bridge support. Just guessing here, but wouldn't that make for tubby tone...?

yes I did it more Martin style. I moved the X braces up but kept the bridge plate where it was

I did the MJ and was told to increase the angle to 100 degrees. I kept the junction point of the X brace in the same location but also tapered the lower bout ends of the braces to end just shy of the kerfing.

I did pretty much what John did. I spread the brace to 98°on the 00, and forward shifted toward the hole.

I used 100° on the project guitar top, and the X was ~ 1 3/4" from the hole. I had no guitar plans in hand, so I searched images on the Internet and extrapolated enough info to draw a plan. It ended up sounding very good, but I think I prefer forward shifted.

Yes, I'm still here :-)

Hopefully getting ready to move forward on this OLF SJ build. Plagued by health issues, family & laziness (actually playing guitar) for some time, but I'm feeling much better.

Tippie:

I didn't like the brace layout. I think it sounded too tight. I opened the X brace to 98 degrees. Moved the tone bars more into the martin position. That was more pleasing to my ear.

I laid out a new template for the SJ w/ a 98 degree X-brace, FS - 1" from the soundhole. Wasn't exactly sure where the tone bars should be placed? Have a Martin Jumbo top I used for comparison & came up with this. ...a-la Martin style. I did not make any adjustments to the bridge plate & bridge & left them in same position as plans. By all accounts, the neck should fall into place.

Think I can minimize (trim down) the bridge plate some...?

SJ


Martin J top

Looks good, but I'm learning that there's a balance between following what others have arrived at through methodology and when sometimes you have to call an audible in order to overcome a mistake. On my second build I went a little too thin with the thickness sander and the top was at the very limit of stiffness. I paid Tim McKnight a visit in his workshop and his solution was this.



He advised me to taper the braces only, no scalloping and keep as much mass on the main X brace as possible. The end of the bridge plate is rounded to prevent potential bridge shear and the edge is profiled to a rounded edge to prevent splitting. The X is 100 degree wide and the junction is 1" back from the soundhole.