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Hi,

While I am looking for a good way to do join mortise and tendon joint, I saw this artical by Cumpino.
I'm curious to who many of you prefer this way to other method that might be out there.

Also, I would appreciated if you can share any updates such as modifications, size of hardware, and source for the hardware since the artical was published. I am especially curious to where you guys buy the hardware.

Also, what do you use to drill holes and control the depth of barrel nuts? any specialized drill bit?

http://www.cumpiano.com/Home/Articles/S ... block.html

I use that method in my M & T neck joint. Over 100 guitars to date with no problems. You can probably find the barrel nuts at any good hardware store as the are a common pieces used in a lot of the knock down furniture you buy and assemble at home (shelving, computer desks, etc).
I like the system because the barrel nut is shouldered in the tenon vs a threaded insert into end grain of the neck wood.
My tenon is .75" wide by .75" deep. The barrel nuts are a bit less than .375" in diameter so there is more than .375" of wood in the tenon to spread the stress over. Since I make the majority of my necks with a laminate center strip, the tenon is very stout.
I have three jigs to perform the joint. One to route the body, one to route the tenon and one to locate the holes in the end block. I'll attempt to add the photos as an attachment, but if it fails feel free to email me off line and I'll send them back to you.

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Hank Mauel

David I used this method on an early guitar and when I was attaching the neck, the heal split right at the lower barrel nut .

Having said that, I know there are many folks who use this method with good success.

I buy the hardware from the hardware store. Nothing special as I just use a but joint with hanger bolts and a nut on the inside. Very inexpensive and every hardware store carries them.

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I do not use the barrel nuts, but simply the end grain inserts. I've never understood the rationale behind drilling two more holes in the tenon.
All the hardware can be bought at Lowe's in the furniture hardware section. Also Woodcraft sells the bolts in black (they're usually tarnished brass or gold).
A 3/8" brad point or forstner bit is all you need, wrap some tape on the bit to get the depth of the insert. Or you can do it free hand by starting with smaller regular bits and increasing the size.
You can hold the neck perpendicular to the drill-press by clamping a handscrew clamp holding the neck blank on the table.
Some prefer to drill the tenon before cutting it, I do after but clamp the tenon with an Irwin clamp to prevent splitting.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

There are several methods of making a bolt-on neck. One of the advantages of hanger bolts is that you dont even need a mortise and tenon, you can make it a simple butt joint. The trick to avoid splitting the neck or stripping out the hanger bolts is to drill a hole, 1/2" or 5/8" dia., perpendicular to the face of the neck, into the tenon (or the heel for a butt joint) and glue in a hardwood dowel. The hanger bolts then screw into the dowel instead of the end grain of the neck. I believe Mario does butt-joined necks this way.
For anyone who doesn't know, hanger bolts are those things that look like a piece of all-thread but have a wood-screw thread at one end and a mechanical thread (for a nut) at the other.

I used the Cumpiano style neck joint on a recent guitar, and i liked it a lot. I used perpendicular grained hardwood bits on the sides of the tenon like he shows in the update on his website, it seems like a good idea, and it is not a hassle to do.

I found the hardware at a local hardware store, for pennies.

I dont really have any reason to like it any more than hanger bolts, but i dont like it less either. I feel like the Cumpiano style is a little bit less prone to splitting, but time will tell. It was definately the quickest and easiest neck set i have done. I would like it even more if i had made jigs like Hank Mauel(thanks for those pics by the way), but it was still pretty easy to do the drilling jigless.

This was my first bolt on neck, after doing dovetails for years, i probably wont be going back.

I have repaired several taylor guitars with split heels, right where the threaded insert is. It seems like when they take a fall, instead of the headstock breaking the heel splits. Its kind of hard to say which is worse, as they can both be easy or problematic repairs, but it is something to think about if you use threaded inserts or hanger bolts.

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Jordan Aceto
Ithaca, NY

A method my buddy showed me for using barrel bolts is to drill a 1/2" hole through the top of the tenon that will intersect with where the barrels will be. drive in a 1/2" dowel and flood it with CA and then drill the holes for the barrels. Works great.

Good Luck

I use a 1/2" dowel (make sure the grain runs parallel to the face of the tenon). I cut a small groove in two sides of the dowel (use the bandsaw with the dowel held by a plier) and use titebond to glue it in. The groove allows the air to escape which also is known as hydraulic action and I can hammer the dowel down to the bottom of the hole.

Then I drill for the hanger bolts (3/16" hole) which is much smaller than the holes required for inserts etc...

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I use the Cumpiano technique and have for the last 5 years. One thing that is nice is that whatever angle the neck is at, the nuts will rotate a little so the bolt hits them as a straight shot. I usually flood the area around the holes with thin CA after they have been drilled to toughen up the wood. No failures that I am aware of. That said, I was brainstorming putting a carbon reinforcing bar down the center of the tenon before drilling the holes. Anyone know of any drill bits that can drill carbon without getting ruined?
Terry

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