Restoration of an old Supertone acoustic

[Phil]

One of the back braces is loose, but I still have to check the top braces (I need to pick up a little inspection mirror first).

[Phil]

I've been doing some work the past few days on this guitar and I must say its been a bit frustrating! I did manage to fix the top cracks, both the ones between the bridge/tail block as well as the crack at the neck block. I also reglued the top to the neck block. My next step was looking at the neck fit, and thats where I got frustrated. The neck angle was off by a few degrees, the nut slot wasn't square to the center line of the neck, and the neck was WAY off center from the body (close to 1/2 inch at the tail block!!!!). Added to all of this, is such a poor dovetail joint - I cleaned out all of the old brown glue and the joint is so loose fitting that if you breath too hard the neck could fall out of the body!!!! No wonder the neck moved so much with such a bad fitting joint - the only thing holding the neck in position was probably glue! I've tried playing around with shims in the joint but I have to adjust the heel SO much to get the alignment and neck angle that I just can't get the joint to work out for me. I'm seriously considering putting some inserts in the neck and converting it to a bolt on neck.

[Ben-Had]

Do you have any neck reset experience?

[Phil]

Not really. I set the neck alignment/angle on my Martin kit guitar butthat was a mortise and tenon joint. I did a reset on a Art & Lutherie acoustic that someone gave me because the bridge had pulled off it and the neck angle was also out of whack, but once again that was also a bolt-on. I did watch all of John's dovetail neck setting vids on youtube though, which certainly helped me understand dovetail joints. This guitar would need some rather large shims in the joint to get it anywhere near tight.

[Ben-Had]

I've had to build up the dovetail before to get a good fit then it's usually just a matter of following the steps -ACE (neck "A"ngle, "C"enter line, "E"levation). Work it like John's video until it fits. You'll probably have to remove some cheek wood to get the correct neck angle, then floss it to fine fit it.

[Darryl Young]

I've had to build up the dovetail before to get a good fit then it's usually just a matter of following the steps -ACE (neck "A"ngle, "C"enter line, "E"levation). Work it like John's video until it fits. You'll probably have to remove some cheek wood to get the correct neck angle, then floss it to fine fit it.

Doesn't the dovetail mortise need to be reasonably good to allow the neck to be adjusted? Might be less work to make the a mortise and tenon by widening the dovetail mortise till the sides are flat and gluing wood to the sides of the dovetail and trimming it off square to fit the new mortise. Then you could convert to a bolt-on if you wanted.

You could also cut the tenon off the neck, glue wood in the dovetail mortise to fill it in, and then convert to a bolt-on with a flat surface (no mortise or tenon). Several folks make their necks this way and with no tenon in the way, it makes sanding the neck to the proper angle easier.

[Ben-Had]

I converted a dovetail to a bolt-on once but not changing a thing and just inserting the bolt in the DT tenon. Actually worked pretty good. But if you do that you lose the experience of trying to fit that old joint.

[johnnparchem]

I only reset one dovetail so take any advise from me with a grain of salt. If the dovetail joint is loose ignore it until after you have adjusted for angle and center. You have to adjust the angle and the center on a bolt on or a dovetail. I find it is easier if the dovetail is loose enough to fit the mortise all the way in to adjust the angle and center. If you are taking a bunch off the cheeks to correct the angle make sure you cut some relief between the cheeks of the heel and the tenon. Make sure you have good contact with the body while setting the angle and center and that you are not sanding a curve. I switched to chisels and scrapers because I can only sand curves.

Once the angle and center are correct then put on some shims to the mortise and carefully work each side (leaving the cheeks of the heel alone) to drop the neck in. While doing this I dust the mortise with chalk to see where I am striking the tenon. Sanding off only the clalk off assures that you are making good contact while you are dropping the tenon into the body.

After a few tries trying to get a tight fit for the dovetail you can always turn it into a bolt on. But really you done the hardest part once you set the angle and the center.

[Zen]

How did this work out for you ? I have a very similar problem with my kit build. Very loose joint on the neck and the angle is miles out--I cant get the neck to pull back and I am a bit scared of taking too much off so its shelved for now until I gain more experience


Rusty

[Phil]

Well, the guitar works..... but I'm not 100% happy with how it turned out as a whole so I will probably do a little more work on it one day when I get bored. The neck is nice and solid though. I'd love to have fixed it the RIGHT way but I just don't know if it would have been possible with the skills I possess.