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I really didn't need more projects but I just couldn't help myself when I found a -47 Gibson L-7 neck for sale. I was wondering has anyone used an old archtop neck to build a flat-top? On Gibson archtops the dovetail is cut to the neck all the way through and there is about 3/8" thick shim between the top and the fingerboard that's easily removable. The neck angle might be a bit more than usually cut on the neck but that can be compensated.

I was thinking about building a "Gibson" that Gibson never built with J-35/45 body-style and bracing but with moustache bridge and split inlays. Something like this but with the Southern Jumbo inlays:

Has somebody experimented with different bridge desing on same guitar? I really like the look of the moustache bridge but how does it sound? Is it too heavy to sound good?

Here's the neck. Long scale by the way and the depth at the heel, from the bottom of the fingerboard is about 93mm which is pretty close to J-45 Gibson spec?

That would be a handsome instrument.
Probably could be done - try it, and keep us informed.

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

Thats a cool looking headstock but the pickguard looks like somebody slapped it on without trimming it to size...

I don't see why that neck wouldn't work... Will it attach at the 14th fret? What is the scale length (I believe the J-45 has a 24.75" scale) and how will it match up with the bridge patch? ...make an adjustment? ...personally, I'm not a fan of the moustache bridge... to each there own...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

If I am understanding your post correct that picture is some kind of composit? That is not an L-7.

An L7 is an archtop guitar and what you are showing appears to be a J body.

If I owned that neck I would not try to build a guitar around it. I would either try to find an L7 that needed a neck or I would sell it. A complete 1947 L7 is worth somewhere in the neighborhood of $4,000. So it is something that has much more value than building a different guitar out of it.

That is just my 2c from the perspective of a repair guy...

And as you can probably tell from my avatar I am a Gibson fan...

Cheers,
Bob

I wan't seeing the pictures of the neck below so It does look more familiar to me.

That appears to have been cut out of a body. My guess is because someone couldn't figure out how to get it out? It appears to have some kind of paddle joint but I am not aware of them putting them on the L body guitars but I have only worked on 2 of them before and have not done a neck reset on one.

It also appears that they cut through the neck just above the heel? I am sure it could be fixed but I still don't know if I would use it for building a guitar around. But that is just me...

Cheers,
Bob

"Thats a cool looking headstock but the pickguard looks like somebody slapped it on without trimming it to size..."

Re the pickguard: I have a picture of another Gibson, which was sold at Elderly, with an identical pickguard shape. It was identified as a 1941. That guitar has a bridge that comes to a point at each end, with a third point in the middle of the bottom. I believe both the bridge and pickguard on that 1941 Gibson were original.

Re the neck: Given the work it would need to cut down the fretboard extension and reshape the dovetail heel, and the long scale, I personally would be inclined to use it for an arch top instrument rather than modify it for a J35/45 type of flat top.

Re how the Gibson mustache bridge sounds, that may be hard to answer to find. If one person says it sounds good and another says it sounds bad, what does that tell you? A question easier to get an answer to would be how much does the mustache bridge weigh compared to a belly bridge. Still wouldn't tell you the effects of its larger footprint but you might be able to extrapolate and have some idea based on how you like the sounds of lighter vs. heavier bridges.

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Tim Allen
"Never hurry, never rest."

I guess my first post wasn't really clear enough?

The neck I got is from a -47 Gibson L7 archtop, it's all original and solid. It's been steamed off the body and it's all intact. On the original construction the fretboard end is about 3/8" above the soundboard and there is separate shim plate that's glued on the bottom of the fretboard and that's easily removed making the neck suitable for a flat-top however the neck angle might be a bit more than usually on flat-tops.

The first photo is of a 1939 Gibson J-55 which I think it's one of the coolest looking Gibsons ever. It doesn't not have the same inlays or the headstock shape as on the neck I have but I was thinking that I'm going to build the same size and shape body and use the same moustache-style bridge.

Many of the early Gibsons with moustache bridges were built very light overall, including the bridge. A moustache bridge can be built with every part of it being thin. I suspect that this thought was actually in the designer's mind in the beginning. By having the cutouts in the bridge it could be light and still spread the stress: wide wings and a good distance of the pins behind the saddle.
I'm guessing that it is ignorance and laziness as well as the difficulty of making a moustache light that led to the many J200s with ungodly massive bridges. Light mustache bridges on a production line would be subject to cracking apart before or during assembly.

Man, that neck is beautiful. Here's my lazy daydream about it:
I can't help but think that if I wanted to build it into a flat-top I would build it with a variation on what classical guitar makers call "spanish style heel." In other words, make a building board that the guitar assembles on. The top of the guitar rests face down on the building board. The strong rigid building board has an extension for the neck. You assemble the top, neck and sides on this board and thereby the neck angle is controlled. The final step is glueing on the back.
My logic is this: if the old neck has no kinks above the 12th fret, then I have utmost respect for the old wood and glue that the Gibson guys put there. Why cut off that wood under the highest frets if it is proven through time to be holding the fretboard perfectly? By using the spanish construction method I could cut out an area in the top to fit on the neck as it is. Then I could link the top, sides and neck together by adding the neccessary pieces of wood to build up the "end block". I would be doing it all in plain sight with total access. I'm thinking small light pieces of wood in keeping with the old light Gibson theme. Making the building board would involve thought and precision, but after that you don't have any of the cut-the-dovetail-exactly-right worries. The building board controls the neck angle.

I think it would be difficult to use that on a flat top. It's a cool neck, I'd get Benedetto's book and DVD's and build an archtop body to go with it.

Another option. Check out Dan Yeager's site, Acme Archtops. (http://acme-archtops.com/vzeouc4e/acme-archtops3/) You could get prebent sides and a laminated top and back from him. A mounted or floating pickup and you'd have a really cool instrument with some real mojo.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I've got some time tomorrow and I'll measure the neck angle on the neck, let's see if it's good or not (or easy to do or not). Meanwhile I bent a set of Padouk sides and joined the Padouk back + an European Spruce top. I'm still thinking about the binding scheme and the overall look but I guess I'm going to go with pretty simple binding just like on the Recording King Ray Whitley + use a belly bridge like on the original 40's GIbson Southern Jumbos.

The spacer piece under the fretboard came out nice and easy, seems like Gibson scored the bottom of the fretboard before gluing?


The angle on the neck is 87,5 degrees which is more than needed but with 1,5-2 degrees slope on the upper bout + radiused upper transverse brace it should be OK.


I also did the rosette, it's sort of like the Gibson Nick Lucas Special but not quite. The plan is to use the Southern Jumbo style belly bridge but with the J-35 style pickguard.

Toothing Iron Nice project, I have an AJ under way.

Here's the top and back


And I'm done!


And a note to self: Shellac + black paint on top is a bit too difficult to get right with my skills and patience..

It's terrific! Well done.

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

Awesome!
Love the white on black.
Looks like the neck was made to match the body.

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