slim hollow body with P90

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Freeman Keller
Posts: 443
Joined: Mon Feb 27, 2012 11:34 am

Re: slim hollow body with P90

Post by Freeman Keller »

Graydon, I hope I didn't get too carried away with my previous posts. What I was trying to do is show several guitars built in entirely different fashions with entirely different goas in mind. That way I hoped I could talk better about what it is I think you want to do.

Lets just briefly go over those guitar. The first is an acoustic guitar built somewhat like an archtop but without carving the top or laminating it. I simply push the dome that we build into any acoustic about as far as I thought I could - I normally use 25 foot for my tops and 15 for the back, I just pushed a piece of spruce to that 15 radius and hoped for the best. That loads a lot of stress into the top that a carved top would not have. Its pretty much what McDonald was doing in the GAL article. I just put a pretty big X brace in to try to hold the dome and the bridge plate because I knew there would be a lot of down force.

The guitar worked, it sounds pretty much like an archtop instead of a pinned bridge steel string. Don't expect that method to give you much of an arch however unless you do something to actually form and mold the top.

That is what the yellow one is all about. That is a three layer lamination pressed into a mold while its being glued up. This is how Gibson (and others) do most of their arched topped ELECTRIC guitar - most of the ES-xxx. These guitars might have an acoustic sound but it is not optimized, they are intended to be plugged in. Since the top is not being optimized you can hang all sorts of crap on it - pickups, potentiometers, pick guards , and if you are going to do that you should put in braces to support them. I'm trying to show that in the picture of the yellow guitar. That style guitar I call a hollow body electric" to differentiate with a true archtop.

The next red guitar is what most of the industry calls a "semi hollow body" (or somethimes semi solid body). Again, its an electric guitar, no intent to play it unplugged. The top, back and sides are laminated like the yellow one. Its got a great big hunk of wood in the middle to support the neck and components. Because the body is so thin a dovetail won't work so its got the tenon like a solid body.

The last one is a les paul shape but it could be any shape. It has a carved top glued to a chambered solid body, but the body could also be made with bent sides and a thin back. Its just another option.

Going back to your original post and the two guitars you have referenced - here is what I see. They are both laminated tops with significant arching, like the yellow guitar. They have a single P90 in the neck position, that tells me they have some sort of support under the top in that area. I can't tell much more about the construction. The are not cut away.

There were a couple of folks who were making and selling laminated tops, sides and backs, this is one of them

https://archtops.weebly.com/non-cutaways.html

I have another that I could PM you if you want to pursue this.

Hope this helps, I'm trying to give you some background rather than answer specific questions.

Freeman

Graydon Stephens
Posts: 11
Joined: Thu Sep 17, 2020 10:34 am

Re: slim hollow body with P90

Post by Graydon Stephens »

Yamaha AEX 500
Yamaha AEX 500
Freeman, I have found my solution, see attached photo of Yamaha AEX 500. This is a flat top, yet has the aesthetics of the archtop models I had been inspired by. It is thin body with bolt on neck. Has piezo under the saddle and neck humbucker, and a means to blend both pickups. I'll omit the piezo and just go with a P90 at neck position. I might exclude the cut away. If I do go cutaway it will be florentine. Thanks again for your input, hope you didn't't think I was going to hound you with questions. Regards

Freeman Keller
Posts: 443
Joined: Mon Feb 27, 2012 11:34 am

Re: slim hollow body with P90

Post by Freeman Keller »

Sounds good. I'll just make three brief comments, you probably are very aware of all of these.

First, work out you geometry very carefully. Have the bridge that you are going to use in your hands, lay out the amount that the top will be arched (it will not be totally flat), the neck angle, the overstand and any wedge under the fretboard extension. I've done a couple of write ups about how I approach geometry - it you would like I can send it to you.

The Yamaha has a very funky bridge/tailpiece which you will either have to duplicate or come up with something equivalent. I ran into something similar on a ES-225 that I worked on (it didn't have the piezo).
1211191420.jpg
If you use a more conventional floating bridge and trapeze tailpiece you may not be able to get enough break angle with your flat top. (note that the 225 is another slim bodied guitar with a P90)

Third, consider your bracing and what you want it to do. You need to support the pickup somehow, You (probably) need some support more or less under the bridge. You need a way to connect the neck. If the body is deep enough that would be a dovetail but for a "slim hollow body" you might have to go to a M&T like Gibson uses. All of this comes back to the geometry question.

I guess there should be a fourth - show us some pictures when you do build it. And if there is anything I can do to help, let me know.

Matthew Lau
Posts: 515
Joined: Sat Feb 18, 2012 2:03 am

Re: slim hollow body with P90

Post by Matthew Lau »

Lovely work, mate.

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