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I have been cutting my neck tenons with the tablesaw which works fine, just wondering what the benefits are of using this type of jig. I was hoping someone would have some pics to post showing the jig in action, the positioning of the body on/in the jig in relation to the neck...isn't this how the neck angle is precisely determined? I was also wondering how/if there is a way to make the slight back angle of the shoulders of the neck tenon area that fit up against the sides or is it necessary to come back with the floss method to accomplish this. Lots of questions I know, but if this jigs makes things easier and more accurate I'm interested.

Greg

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Gwaltney Guitars

the beauty of the neck jig is that it measures from the body the angle at which the router will cut the heel cheeks to set the neck angle to match the bridge/top arch combination.

i believe the photos you desire are in the archives.

Greg, I've recently switched computers (read: my old one took a dive) so I don't have any pics right now.
As Michael said, on this jig, the angle is determined by the angle of the body. Which is exacly how we want it. No matter how hard we try, it's almost impossible to make a side to top angle perfect every time. This jig uses that particular angle and transfers it to the tennon.
On the undercutting of the cheeks issue: It's as simple as putting in a smaller router bit and lowering the cutting depth a bit. I do it on every neck.
BTW: I said this when I put out my version of this jig, but it is not, I repeat, not my design. I designed it to be a benchtop model and came up with the depth screw at the top of the rail which compensates for fretboards and frets. But the initial design is Charles Fox's.Pwoolson39022.4492824074

Thanks Paul, I know a picture would be worth a 1000 words(questions in my case). Anyway, I understand the concept, just wondering how the exact angle is transfered to the jig....do you just measure the angle by hand and transfer it to the jig, or is the body of the guitar mounted on the jig to aquire the angle, if so how is the guitar body situated on the jig in a stable enough fashion to get a perfect angle/fit. I'm sorry if I'm just not getting it, please help if you can.

Thanks,
Greg

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Gwaltney Guitars

Hi Greg,
The body of the guitar is mounted to the jig...here are some pics that might help.
Craig

That helps a lot Craig...One last question, how the heck is the guitar body fastened/secured to the jig? Is it somehow attached at the bolt area on the aluminum rod? or is it just sitting up there.

Greg

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Gwaltney Guitars

Thanks Craig, those where the pics that I lost in the computer crash.
Greg, the body does't get fastened to the jig at all. This is for the tennon only. You use the body as in the second pic to get the angle of the side to top at the neck joint. With the side sitting flat on the top of the jig (as shown) the whole plate that holds the neck can swing. When the al bar sits perfectly flat on the top and the bolt is just touching at the bridge location, that's your perfect angle. Tighten it down and have at the tennon.
The bolt: here's how I figure it. If I want a 3/8" bridge I want the fretboard to be in the same plane as it is. So if the fretboard is .25, I would subtract that from the thickness of the bridge leaving me .125. That's how far I want the bolt sticking out toward the body. It's perfect when the side of the guitar is flat on the top of the jig, the aluminum bar is flat on the fingerboard extension and the bolt is just touching at the bridge location.

Thanks Paul, I think I get it. As far as cutting the cheeks, how small of a bit do you use and how much deeper do you go, graduated depth toward the tenon? I'm getting this vision of a jagged edge doing it this way, a stair-step affect on the cheek, hopefully one more explanation will do it.

Thanks,
Greg

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Gwaltney Guitars

You don't really need to do much to over complicate it. You really just want to get that wood out of there. I think I use a 3/8" bit and just make one pass about 1/8" deep.

there is nothing to prevent you from adapting the jig to route the mortice in the body as well.