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I was about to bolt and glue the completed neck on the completed body . . . when I realized that my neck angle is overcut.
The straight edge on top of the frets lands 1/8" higher above the bridge than it should. The strings would be sitting 5/8" above the top. Embarrassing screw up.
Rather than trial and error, does anyone have a formula that would tell me how much I need to shave off the top part of the heel to correct for this? I'm affraid that it's going to be so big that it'll mess with the 14th fret. I'll make a new neck if I need to.

Any help??

Thanks in advance.

Phil

I think it should just be a simple ratio. Say your heel is 3 inches, and the distance to the bridge is a foot. If you can adjust the heel so that it pivots on one end with no loss,1 mm pivot should be 4 mm at the bridge.

Is it fretted? You could take down the fretboard some too.

Mike

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Mike Lindstrom

I couldn't tell you myself, but this is something I came across that may help you out Phil.http://www.liutaiomottola.com/formulae/Reset.htm

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

His equation should work, but it's based on adjusting the action at the 12th fret. I understood you to be talking about height at the bridge. Either way works fine. Just make sure you know which one you're meaning to use.

Mike

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Mike Lindstrom

Here is a formula that will work.

X = (D * B) / A

D = difference in existing height of strings to top of bridge less target height to top of bridge.
B = length of heel (not including fretboard)
A = distance from body joint to saddle location.

I like to use a strip of masking tape to mark the cut.

Here is another option:

http://www.tundraman.com/Guitars/NeckAngle/index.php

Formulas are great to know for a new build. In your case: insert a thin, tapered shim at the bottom of the heel until you've got the angle and string height you want. Then mark the heel profile to the body joint. Foolproof.

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Wes McMillian
Santo, TX
http://www.wesmcmillian.com

Is it not possible that if you go ahead with bolting the neck, and gluing down the fretboard tongue, that the string tension will pull the neck into alignment ?

After all, the straightedge on frets to bridge parameter is only meaningful once the instrument is under full string tension.

If the straight edge still indicates high, (and it will almost certainly read a lot less high than the current 1/8") then you could rip the frets, sand the fretboard, and refret.

A hassle, but a lot less hassle than redoing the entire neck.

Phil, I wouldn't have thought 5/8 was too bad for a string height with no string tension. 15.7mm. You will lose a bit as it tightens up with strings, and the top may pull up slightly unless its over braced. I would usually aim for 14mm. If everything fits well I would just go with it. Perhaps just tack the FB extension down first, string it up and see how it goes. Then make some adjustments if it is not the sound you want.
Dom

Phil: I think you should take Dom's advice and string up your guitar and then determine where you have to go. Just bolt and do not glue anything. The fingerboard will just sit on the top. Don't worry about gluing until you get all else squared away. The top should raise some and most likely you will have to temove very little at the neck. Most likely will not be noticeable at the 14th fret. What you have to look out for is the ski slope effect on the fingerboard extension.Good luck.
Tom

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A person who has never made a mistake has never made anything!!!

Exactly why I love this forum!! Thanks guys.

Mike, it's not fretted. I just filed the tang off of two fret pieces so I could lay them into the first and 12th fret.

Wes, the shim idea is brilliant in it's simplicity. Don't know why I didn't think of it - but I guess that's what this forum is for.

Seeing as Ron offered the formula, I did the math and found that I needed to taper off about 1mm. So I went ahead with that method. I still need to spend a bit more time dressing up the new fit, but I've now got the whole thing in what feels like a better ball park. The straight edge lands just a bit above the bridge. I think I should be in good shape to glue the whole business together tomorrow.

Thanks again for the help!! It's been over three years since I've finished a guitar. I was never that good to begin with, and now it feels like the few chops I had are way rusty. Sure is great to have this forum for answers and encouragement.

Phil