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What is the reasoning behind the brace "box" around mounted humbuckers? I've recently had a Benedetto, Super 400 and an L-5 in the shop and they all had these "ladder" braces in between the parallel braces. The Gibsons also had these finger braces going from the outside of the brace towards the sides, which seems pretty redundant given the top thickness on the L-5 was 9/16" thick (measured in the pickup cavity)! I just can't see how the tops on these would require that much extra bracing.

Interesting, I never knew that.
I assume it would be for feedback prevention by firming up and isolating the pickup area.
It may also add stability to the area of the top which has been weakend by the pickup holes.
Thats my guess.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

I think you'd have to ask Gibson about the S-400 and the L-5. My guess is that this particular L-5 was never intended to be played acoustically. If that guess is correct, then why go to all the effort to thin and graduate the top? In fact, why thin it at all? This instrument might have been a product of the Gibson custom shop and built to the customer's specs. It is very curious, indeed. 9/16" thickness suggests to me that at least some thinning and graduating was done on the instrument. It seems very odd. Obviously, it is not built the same way as so many great L-5s of the past.

As for the Benedetto, why not just call Mr. Benedetto and ask? I expect he, too, was satisfying a customer request, or perhaps he felt that particular top needed the reinforcement that he built in.

All conjecture on my part, of course.

Patrick

Well the L-5 was not a custom guitar, the Benedetto was. However, knowing the owner, he wouldn't have specified anything about the bracing. My Gretsch 6120 is braced the same way now that I think about it. I also can't see how the hole needs to be supported as there are plenty of Gibson's from the thirties with Charlie Christian pickups that don't have any extra bracing. I can't think of a good reason to add those extra braces but Benedetto, Gretsch and Gibson spend man-hours installing them so there must be something to it. I may actually try and email or call Bob Benedetto and see what he says.

I would say that the ladder bracing for the pickup hole is just good woodworking practice especially on a thin top.
Granted, there isn't a lot of stress in this area but the corners of the cutout tend to be stress risers that MIGHT allow the top to eventually crack.
Not so much on a 9/16" top thickness.
As for the reason for thinning the top at all, perhaps just a weight reduction.

Send Bob an email and ask him...

Tend to agree with Nelson...just good practice to "bridge" between beams when there's a cutout (as seen throughout all construction). Braces running adjacent to a hole and parallel to grain puts the top at risk of shear along the brace if you hit it. Bridges overcome that. It's the way I'd do it, although I'd stay with around .250" thickness down the center (..almost 3/4"???...really??)

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Dave
Milton, ON

Nelson and Dave, I guess that makes the most sense. Still seems a bit much for laminated guitars but they are there none the less. Yes, it really was 9/16" thick! I have pics of it on my old computer I'll try and get them.

Here's a pic of the L-5 top so you guys don't think I'm crazy.

Wow! That's a lot thicker than I expected to be.

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"Act your age, not your shoe size" - Prince

I think it has something to do with tone. On my electric archtop, I just braced with a Y brace on the lower bout. Alot of builders refer it to a tonebar.

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Jason Moe
LaCrosse WI 54601