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Good afternoon all -

I'm working on my second mandolin, this one a carved-top A-style.
Siminoff's book is my primary reference. I've glued up my neck blank,
and before I cut the neck out of the blank, I'm trying to think ahead to the
neck joint.

Siminoff basically cuts a "V" into the headblock that matches the shape of
the end of the neck, drops the neck in, and pins it with a couple of glued
dowels. It looks reasonably simple and solid.

An alternative would be an old-fashioned dovetail, though I'm not feeling
that ambitious today. A more serious alternative for me would be a
straight mortise and tenon, which is what I used on my last guitar.

Any advice on these or other style joints?

Thanks!

Jay

PS - to answer where I fall on the "Simnoff inside-first versus everyone
else outside-first" plate carving debate: I took Mario's advice and did the
outside first. He was right (imagine that) - it's not that hard to hold the
carved plate upside down to carve out the inside. However, I ended up
finding myself flipping back and forth - outside roughed first, then
inside, measure, inside some more, measure, outside some more,
measure, inside some more...

a straight mortice and tenon relies on mecanical fasteners! how would you propose to tivhten them if your ae using f-holes?

I am using f holes, so a bolt-on neck would be fairly well out of the
question. That said, do you really think that a tight M&T with a good glue
(like titebond) would necessarily need mechanical reinforcement?

Siminoff's joint does have the advantage of mechanical reinforcement in
the form of the dowels. But that neck isn't ever coming off without
removing the back plate! Given the trouble I had getting the angle right
on the guitar neck, I appreciate at least the illusion of the ability to
remove and reset the neck.

I have a mando that uses bolts and a butt joint. Just use the end pin hole to get into the body to tighten the bolts. Before putting the back on, just put the bolts in and fit the neck. Put some tape on them to hold them in. Then attach the back. To put the neck on, use a long T handle with a allen wrench soldered on. You could probably use a wooden dowel with an allen wrench epoxied into the end of it. There are multiply ways around it. Good luck!


Tracy

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Tracy
http://www.luthiersuppliers.com

Setting the neck angle right following Siminoff's method is very easy.   You clamp the neck on a work board and make a cradle for the body that elevates it off that same work board the right distance, and glue the two together while in this position.

The gluing surfaces on this joint are quite substantial, but stressed glue joints can move over time, espessially with modern glues like Titebond, so a mechanical lock like the dowels provide is probably a good idea. I think this joint is a very good alternative to a dovetail joint structurally, even if it is not the traditional choice. Neck resets are not as common on mandolins as guitars as their necks are quite short, the instruments don't distort from string pressure to the same degree as guitars over time, and the bridges can be adjusted more easily.

If you use a straigt tenon it will be very thin as the bottom of the heel is tiny, and you will still have to shape the bearing edges of the neck to fit to the curve of the body in this area, which I imagine is the most difficult task with this joint. Arnt39083.7704166667

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Rian Gitar og Mandolin