Neck angle on through-neck Les Paul-style guitar?

[Dave Locher]

As the title says, I am starting a build on a neck-through guitar with a carved maple top very much like a Les Paul. Yesterday I drew it out full size on paper and realized I am not sure how to calculate the neck angle since the top carve will affect it. Do I do some careful math to figure it out, or somehow carve to top before cutting the body portion of the through-neck so I can measure it, or is there some other option I'm not aware of?
I've never owned a Les Paul so I'm just sort of guessing here. I never realized the top tapers down on the pickup plane but now realize it has to do so. Is there some simple way to do this? My top is 5/8" thick.

[David King]

You should probably track down some LesPaul plans to look at. Have you chosen your hardware yet? That would be my starting place if I were figuring this out.

[Dave Locher]

I know what angle I need relative to the top plane. The problem I've run into is that the carved surface of the top is part of that angle. In other words, the back will be at a sharper angle than the top because the top will be wedge shaped between the neck and the bridge.
I think I'll just have to calculate the wedge as closely as possible before cutting the neck's body portion, but I was hoping someone would have a clever shortcut.

This is only vexing me because I'm doing it as a neck-through, which means I have to cut the body profile as part of the neck blank. My one and only previous build was a bolt-on so I didn't have to worry about this at all. But it's what I really want to build.

[Barry Daniels]

Draw a very accurate side view of the guitar, including the frets and the strings.

[Dave Locher]

Draw a very accurate side view of the guitar, including the frets and the strings.

It was when I was drawing it up that I realized I had a problem in the first place, so it's a proven technique for me!
I guess I'll just have to figure it out. It's not exactly rocket science, but then again I'm no rocket scientist...

Thanks for the input, everyone. I love this forum!

[Freeman Keller]

The normal neck angle of a LP is 3-1/2 to 4 degrees relative to the body. Measuring my StewMac LP plans, the body at the bridge is 3/8 thicker than at the sides which seems to work fine for a ToM bridge. The fretboard extension sits on top of the body, it does not stand proud like a Fender or many archtops. One of the nice things about a set neck, of course, is it does allow you to fine tune that neck angle but 3-1/2 degrees has worked for both of the LP's that I've built.



FWIW - before I glue the neck in I do check the angle with the bridge sitting on some little spacers on the top using a straight edge on the frets. This pic is as low as the bridge can go and the fret plane with no relief in the neck.



Get your bridge, tailpiece, and pickup rings and measure the height of each (or get that from the spec tab of the supplier). Lay out your fret and string plane relative to those parts, particularly the bridge. Allow for the adjustment range that you want for your action - you want to be in the range of the ToM. Also the strings will pull a tiny bit of relief into the neck which will slightly raise the string plane

[Dave Locher]

Thank you for the incredibly detailed response, Freeman, and especially for the photos. Just seeing the shot of your body carved up answered about half my questions, and the rest covered the other half. I appreciate you taking the time to share your knowledge and experience.

[Chris Richards]

Just to add a little.... Count me as an additional vote for a full scale drawing..... This is a simple router jig I built to cut a neck an angled neck joint, once you've decided on the angle place a block under the end of the neck to set it in the jig at the chosen angle then simply route around the box... You'll need a short and long bearing guided router bit but that's about it. Also if slight adjustments are needed it's very easy to replace the neck in the jig and add or subtract thickness by sliding the block that gives the neck the angle.

I'd be very interested to see how other people cut this joint...

Hope that helps...Chris

[Dan Smith]

Hey Chris,
Do you use a jig to cut the sides of the tenon as well?
Thanks,
Dan

[Chris Richards]

Hi Dan, I use the same jig to do the lot, I run the bearing of the router bit against the inside wall of the box. I have three different lengths of bearing guided router bits, they're all 1/2 inch diameter but the lengths are 3/8th, 1/2 and 3/4 inch (I think), that way I can cut the base of the tenon with the shortest bit and the sides using the medium and longest router bit just to trim down to the full depth and leave the thin wedge shaped "wings" under the edges of the FB if need be....

[Dan Smith]

Hi Dan, I use the same jig to do the lot, I run the bearing of the router bit against the inside wall of the box. I have three different lengths of bearing guided router bits, they're all 1/2 inch diameter but the lengths are 3/8th, 1/2 and 3/4 inch (I think), that way I can cut the base of the tenon with the shortest bit and the sides using the medium and longest router bit just to trim down to the full depth and leave the thin wedge shaped "wings" under the edges of the FB if need be....

Thanks Chris, I may try to rig up a jig.
Dan