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Good evening
After figuring out my neck angle, I cut my tenon and mortise, and they fit very nice, now my question is this. When I do a mock setup with a fret board I have to force down the part of the fret board that rests on the guitar body. Did I do something wrong?

Thanks....Les

How large is the gap between the sound hole end of the fretboard and the top?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Not in my opinion. It depends a lot on how you approached your geometry. As long as you don't have to press it down too far, you've built in 'fallaway', which is good. I aim to have to press the fingerboard tongue down. I want. I needs it. My precioooouuuussss....

From the top of the sound board to the top of the fret board, is about 3/8", which leaves about a 1/8 gap.
Thanks for the quick replies.

Sounds like the neck angle is out. With the neck in place, fb sitting in place, if you place the bridge onto the appropriate spot you should have about a 32nd gap over thr bridge. The bridge should have the top radius on it. That should give you a better idea of what's going on.

If ur top is domed, this is expected. Sand flat as can or dare the contact portion. At an angle commensurate with the bridge height. I do this with a longish piece of granite that has sandpaper glued on it. Put a dummy bridge in expected location, then sand contact area while riding dummy bridge. Think about the geometry. However, if u underestimated neck angle, this will only get u so far. Then, sand ledges of neck to make the angle right. Done correctly, fingerboard should not bend to meet top.

Like Ed, I aim to have to press the fretboard extension down to meet the top. In my case, I aim for a gap of 1/32" or less. Others may do it differently though.

This is after having sanded the contact area flat by a method similar to the one Mike described above.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

My comments assume a domed top. Plus, be careful that you don't take anything off of the edge at the neck joint. I think folks call this "flattening the dome" ?? If anything, if u already fretted the fingerboard, the FB extension should bow somewhat down (if at all). This can be a complex issue to attack. You need to be Sure this isn't due in part or whole to neck angle inaccuracy. But a domed top naturally means you will telegraph that curvature to the FB extension unless u carefully remove any dome in the contact area.

Once again thanks for all the help. My top is flat, I used Jonathan Kinkaids book to figure out the angle, l guess I am out on the angle.

A fall off of a few thousandths maybe a 1/64 a 1/8 is telling you that something isn't right.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

New builders tend to assume that if we do everything as the resource that we are using says correctly that zip, zam.... all the parts will fit flawlessly.

Wrong.... R - O - N - G.....

Necks have to be fitted, always.... and that 1.5 degree neck angle that some of us discuss from time to time is only an approximation.

There are several toots in the instructional section of the forum such as "Fitting a neck" and "flattening the upper bout" that will help you, Les. Perhaps give these toots a look and then let us know how we can help?

Thanks.

A big part of the correct set up for the neck is accomplished in the correct building of the box before one even thinks about building the neck and fitting it. Good write up in Trevor Gore's book. Sure worth a look if you can get your hands on one.
Tom

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

With a few exceptions Kinkeade's publication is very good. Unfortunately the major exception is that some of his geometric concepts fail the math test. Your problem stems for the fact that there is no upper bout slope machined on the rim to match the neck angle. Like has been mentioned, a little fall off is acceptable and for some even preferred. But pinching the FB extension down to the soundboard can be problematic. Here's my explanation of what needs to be accomplished.

http://www.kennethmichaelguitars.com/neckangle.html

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Ken Cierp

http://www.kennethmichaelguitars.com/

Ken, why would some prefer it? To me it just looks bad if there is an obvious bend. Also I am unclear on what you mean by "slope machined onto rim". My slopes are machined onto the neck ledge at the M&T joint.

Install neck with FB attached. Bolt it on (assuming not a dovetail). Lay a long straight edge on FB and extend to bridge. Where does it contact the bridge. Top edge? A little bit above? Below?

Some pictures would help. Do not press FB down during the test or picture taking. If you built in a 1.5 deg or so neck angle, and your top is truly flat and your sides are truly square, then I do not see how you avoid the bend.

Mike regarding the slope --- it would be easier if you read the article which has been around for many years, it explains how to manually accomplish what is done at the Martin Factory (even pictures) using power equipment.

Personally I like using the straight line formula -- but some like to sand some fall off on the extension and others (like Kinkead) pinch and glue the FB extension down to the sound board. The way I understand the latter, is that some minute additional clearance is achieved allowing a little lower action at the 12th fret.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Ken, are you talking about this? http://www.kennethmichaelguitars.com/neckangle.html

I see what you mean by slope on rim now.

Mike

EDIT: I never saw the link you posted above... I must have thought it was a signature line... sorry

Yes sir, that's the one.

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Ken Cierp

http://www.kennethmichaelguitars.com/

In my case. since the gap at the end of the fretboard is less than 1/32", there is no obvious bend. You can see the fallaway if you place a straight edge on the frets or sight down the length of the neck, but not otherwise. Which is normal if fallaway after the 14th fret is intended. As I see it, you can introduce fallaway either by reducing the heights of the frets above the 14th fret or by building it into the fretboard extension. By doing it with the extension, those frets remain full height so you have the option of filing them down later to reintroduce the fallaway should it be needed after years under string tension.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

After reading KMG neck angle instruction, it cleared up a lot of ignorance on my part. After a little shimming, gluing and recutting the tenon and mortise to the proper degrees I got the FB to sit down on the sound board.
Thanks to all who helped me out.........You all have been a wealth of knowledge.

The guitar that I am building is a copy of a Baden guitar, so with that being said I do not have any plans that I am actually following, rather a little off this drawing and a little off an other drawing, plus my own measurements off a Baden guitar.