Official Luthiers Forum!

I tried a bolt-on mortice & tenon neck on my last archtop (after getting some good pointers from Mark Blanchard) and was very happy with the results. A tutorial was suggested, so here it is based on my current project.
I used 1/4-20 KD bolts & barrel nuts, as I felt they would be more forgiving to the angles involved than fixed inserts. After a spirited debate (not here) about whether or not to glue the extension, I decided not to. The extension contacts the top only as far back as the mortice (no glue), and from there back is totally cantilevered.
Two things you'll need are a 24" long (short flute) bit, and a long shopmade allen wrench. (.300" mild steel bar, cross-drilled for a handle at one end & end drilled for a stub of the correct allen wrench at the other- epoxied in)
The first step is to properly fit the partially shaped neck, re centerline / height at bridge / etc., so it's perfect before proceeding.

_________________
Dave
Milton, ON

......and tighten her up!

Hope this helps.

_________________
Dave
Milton, ON

Awesome Dave to get this tutorial. I am doing an archtop next, after my current OM is well along, so this is timely.

So, no glue anywhere in the joint?

I also bolt on my archtop necks. I use threaded inserts and it is really a pain to get everything lined up properly. Dave's method looks easier and possibly stronger to me.

I don't use any glue... not needed.

Mark

Thanks Mark, and thanks for your help.
I should mention that I graphite reinforce right into most of the extension, which I think becomes more important, given it's not glued.

_________________
Dave
Milton, ON

I run carbon bars up into the extension as well. I think that helps keep the neck extension straight whether the joint is glued or not.

Mark

Dave,

Thanks for the tutorial. It's always nice to have a few pictures to make it clear.

Dave, thanks for posting this tutorial. Very well done and very much appreciated.

What Anthony said.
Nelson

Thanks so much for taking the time to create and share the pics and your method. I'm close to beginning the neck work now on a couple archtops and have wanted to try the bolt-on method. Great timing for me!!

Robert

Robert, welcome to the OLF. As a hint - we really love pictures...

Dave - Many thanks for taking the time to document and post this. I'm planning to move on to archtops soon, once these mandolins are completely done. You couldn't have timed this much better!

_________________
Rick Jones
Rochester Hills, MI
http://home.comcast.net/~rajones19

Does anybody know where to get these barrel nuts with a centered hole? All the ones I've seen the hole is slightly off center. You can still use 'em but it would be a lot better with a centered hole.

I just sand down the long end of my (Woodcraft) barrel nuts until they're symmetric about the hole; also because the 3/4" barrel nuts always seem to come out at ~0.78" or more when I mic them, so one end is always sticking out the end of a 0.75" tenon.

_________________
The member formerly known as erikbojerik....

If you shop around a bit, you'll find shorter ones. Mine (shown in the first pic) are under 1/2". (I can therefore make the barrel holes blind, which locates them laterally.)

_________________
Dave
Milton, ON

thank you

Padma

_________________
.

Audiences and dispensations on Thursdays ~ by appointment only.


.

Pretty darn cool.

_________________
"Act your age, not your shoe size" - Prince

Thanks