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Hi all.

I unglued a dovetail neck today. It was my first and it didn't go as I expected, but I got the neck off anyways. Maybe some of you guys will be able to let me know how I could have solved this differently.

Here's how it went...

I first unglued the fretboard extension with my standard iron and bridge/fretboard extension removal knife. All went well here. I then proceeded to remove the 15th fret and drilled two holes through the fretboard kerf. Again, all went well. Then I started to steam out the neck. After a few minutes (2 or 3), I noticed I could move the neck quite a bit but it actually was the entire neck block that was moving! The top was unglued to the neckblock. Also, the sides would not give up at all; they were glued to the neck heel for good! I strongly felt that all would fall into disaster if I kept on steaming this neck joint. So I went a different route: I unglued the fretboard entirely, sawed out the joint between the neck heel and the sides, then applied steam once again (directly into the dovetail joint, having access to it easily now that the fretboard was off). after a few seconds, the neck came off.

So are the problems I encountered common? (top ungluing from neck block and sides solidly glued to the neck heel)

Thanks for letting me know what I did wrong!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

It would appear there was too much steam for too long. Not by the time frame you mentioned but that the top and block started comming loose. Did you have a neck removal jig setup and in place? As soon as the neck losend even a little, I put some presure on the heel pushing forward. I made a jig simular to what you see at stew-mac.

Also, did you score a line around the entire neck joint? This seperates the finish in that area. It can be quite strong and hold things together more than you might think...also it allows steam to flow out the joints instead of being kept inside the joint.

Joe

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Joe

Alan,
You say you drilled two holes through the fretboard kerf. Do you mean the fret slot where you removed the fret?
You should have drilled a hole approx half way between the middle of the fretboard and the edge, to keep from drilling into the truss rod. You then should have felt the empty pocket between the neck block and the dovetail on the end of the neck. Then inserted the needle and steam.

Could you feel a hollow area? and did you use a neck removal jig to press out the neck from the body as you were steaming? What brand of guitar were you working on?

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

PS: the picture above was not a dovetail it was a mortise tenon...it was the only shot I have of the neck jig. Accoustics get two holes just outside of the center line if the trust rod adjustment is in the sound hole and down the center if the trussrod adjustment is at the headstock.

Also, had the neck ever been off before? If it was glued with Titebond, the body joints may fail before the neck joint if the steam can't escape out the sides of the neck.

J

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Joe

Thanks for your replies guys!



No I didn't have a neck removal jig. I guess it would have helped, but I doubt the solution is entirely related to this.



I didn't need to; it was clear that the neck and body were finished separetly, then glued together.



Yes I did mean the fret slot.



Maybe that's were the big mistake is: drilling two holes instead of one. But were would the steam go out with only one hole? Wouldn't the pressure rise too much? The steam can't escape through the neck heel/sides joint right at first, can it?

Thanks!

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

the neck jig puts presure on the heel and the minute that the glue softens the neck moves forward. You then pull the steam off and wiggle the neck forward and off. It happens very quick with old hide glue. If the neck moves forward a little but won't wiggle out, use a little more steam and turn the neck jig handle one or two more turns. it will pop right out.

I drill two holes on a dove tail and stick a wire down them to ensure it slips in the dovetail slot. There is really only a 1/16" slot between end of the dovetail and mortise. Also the dove tail is only an inch wide or so, so the holes need to be pretty close to the center.

You can turn over the neck and look at the holes you drilled. Did the enter along side the end of the dovetail? Also, its not always the same fret on all guitars. Usually it is the fret just after the body joint. On a 14 fret its usually the 15th one....but not always. If you slip a blade under the fingerboard you can tell where the end of the dovetail is while its on the guitar. Pull it out and lay it on top of the board to ensure which fret to pull. On the 57 in the picture, I originally was going to drill the 17 (neck body joint is 16) but after placing the blade under the board, I realized that it was actually at the 19 or 20th. It turned out to have a long neck tenon like a les Paul and not like the 56 version of this same guitar.

Joe

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Joe

The two holes seem to by drilled correctly, landing in the dovetail slot. I guess all went well except for the sides that kept on sticking to the neck heel. I really doubt a neck removing jig would have solved this issue, but I'm sure going to make myself one for the next job. At least it will eliminate this variable...

By the way, the guitar is a Lys, it's an old Canadian guitar brand, some sort of an ancerster of Seagull.

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)