# Guitar neck joint



## tdale (Feb 20, 2012)

I got my body and neck blank back from the cnc guy today. I' making a guitar/neck joint like Tom Anderson does. That means that the neck pocket has a flat bottom, with 45degree side walls, with a matching neck. The idea is that the wedge shape will hold the neck and body really tightogether. 

The problem is that there is a slight gap between the bottom of the pocket and the neck, which will crack the body if the screws are tightened. Any ideas what to do, except sanding the sides of the neck, which will ruin the smooth sides..


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## Dave Paine (May 30, 2012)

I think your choice are :
a) Sand the piece to fit
b) Add some wood filler to the pocket, then sand to fit the next
c) Use a gap filling adhesive, like 2 part epoxy.


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## DannyT (Apr 26, 2011)

is the neck the right height for the bridge where it's at now or does it need to go all the way down. did the cnc guy cut it right?


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## tdale (Feb 20, 2012)

Not sure wat you mean.. The neck needs to touch the botom of the pocket, or the body will crack when the neck is wedged down...


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## DannyT (Apr 26, 2011)

a picture would make things clearer. could you cut a thin shim and epoxy it in place to fill the gap?


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## Wheeler (Sep 27, 2012)

"Wedged down"? You're going to wedge the neck joint?


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## tdale (Feb 20, 2012)

Do a search for tom anderson neck joint. I don't have a picture here, but basically, the side walls of the neck pocket are 45degrees, and so are the sides of the neck that go into the pocket...


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## Wheeler (Sep 27, 2012)

Well hey, I've been playing guitar for years and I've built a few too but still... That neck design is new to me. It's sort of like a dovetail in design, but not... obviously. 

To answer your question... If it was cut on a CNC then it should be perfect so either you measured it wrong or CNC guy made a mistake. It only takes a typo to bollock something up on a CNC machine. I'd double check all the measurements first and if they are (somehow) correct then i'd probably consider altering the body joint to fit the neck. As said earlier... It's hard to tell without a good photo. =]


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## DannyT (Apr 26, 2011)

after finally finding a picture of the neck joint its obvious that the body wasn't cut wide enough or the neck was cut too large. so either sanding the neck down to fit or enlarging the opening in the body to make it fit right are the two options if you want it right. i don't see any advantage of this joint to the traditional neck joint other then you risk chunking the side out if there is any sideways movement of the neck


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## tdale (Feb 20, 2012)

The traditional joint alows for sideways movement , while this doesnt' move at all, unless you break the body og course. I guess that's the point, not allowing any movement, and a very tight fit

If you manage to break the body, there is something wrong with your playing style


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## Wheeler (Sep 27, 2012)

I might be having a dumb moment but I don't see how that joint stops movement... If anything it would only increase movement. I'd be interested to see how it actually works so I might give it a try sometime...


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## tdale (Feb 20, 2012)

A traditional neck has a flat bottom, and the pocket is flat too obviously. The lower side of the pocket has no vertical wall, so there is nothing preventing sideways movement, other than the screws, so they have to hold the neck down, and hold it in place sideways too. In Tom Anderson's design, the screws hold the neck down, and because there are 45degrees side walls on both sides of the pocket, the neck is held tighter to those walls the harder you tighten the screws. That way, the screws only hold the neck down, while the body holds it in place...


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## tdale (Feb 20, 2012)

This is just a quick drawing. The point is that a traditional design has support on just one side, more or less. So even if the screws are tight, it's possible to move the neck sideways. On Tom Andersons's design, the neck actually has to lift itself from the pocket in order to move sideways, since there is support on both sides, and the walls are angled...


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## tdale (Feb 20, 2012)

This photos shows what it looks like. This is an old joint, he started using a vertical inner wall later,


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## 2lim (Aug 30, 2009)

..... or you could just make a neck joint that has a vertical wall on both sides......

Either way, with what you have now, I would suggest a small shim to take up the slack. Of course, your design will actually require a VERY small gap that disappears as you tighten the neck screws down.


Simon


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## Wheeler (Sep 27, 2012)

I've never seen / heard of any guitars that have had sideways movement in the necks... I'm not sold on this idea but I am actually going to try it just because it's unique. Maybe then the benefits will become obvious to me =]


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## tdale (Feb 20, 2012)

Yes, I need that tiny gap to get preassure on the side walls. Vertical walls won't give me any oreassure , and that's part of the reason I want the angled sides..


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## tdale (Feb 20, 2012)

Me neither  but I like the way the design keeps the neck really tight to the body, which is good for sound... But then, why not go for a glued in joint...


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