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I saw this 'Martin' neck on eBay...



Is using a single bolt attachment:
1)common at all? Would you use it?
2)mechanically sound?

John

Bolts are cheap and isn't more always better in all aspects of life?
I will always use two.

I have thought of a single-bolt system which would work and be mechanically sound but, in the end, I think it would be more work than it's worth.

With one bolt you need a pivot of some sort in the system for it to ride against or there just won't be enough stiffness against vertical movement of the neck (assuming guitar is on its back).

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I believe Martin glues and screws these necks, but I may be wrong. I
remember Mike Doolin talking at GAL this summer about using a single bolt
on one his personal instruments and his system worked fine with a single
bolt. He was concerned with how the general public would react to the
single bolt.

The old clock key adjustable necks were a single bolt design as well.

Louis
Louis405239110.6522453704

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- Louis Freilicher

Oh No! Not another learning experience!

I am a noob at this, and the very thought of using a single bolt horrifies me.

I have built a mortise and tenon bolt-on (cumpiano's new method of using TWO furniture bolts)...five pairs of strings are gonna need all the support they can get...

That just doesn't look strong enough for me, unless it was a dovetail/bolt-on hybrid..

Sam,

Remember that the string tension is actually pulling the top of the joint tight into the neck block. It could be an arrangement for those that love the "bendy neck tremelo" Dave White39110.7163773148

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

I have a Martin 000-15 that has one bolt. I am positive that they still glue.
The only reason that they use the one bolt is so they can get rid of the
guitars faster. Which brings me to question why you would use any bolts
unless you are anxious.

I've built several using necks from Martin. What has already been said is correct, they need to be glued as well as bolted. Once the tenon sides and the fingerboard extension are glued and the bolt is tightened down it won't go anywhere.

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Dave Rector
Rector Guitars

[QUOTE=Dave White] Sam,

Remember that the string tension is actually pulling the top of the joint tight into the neck block. It could be an arrangement for those that love the "bendy neck tremelo" [/QUOTE]

Like I said, I'm a noob...this is the way I learn..

[QUOTE=Dave Rector] I've built several using necks from Martin. What
has already been said is correct, they need to be glued as well as bolted.
Once the tenon sides and the fingerboard extension are glued and the
bolt is tightened down it won't go anywhere.[/QUOTE]


I have seen a few of these type neck joints in the repair shop where the
neck heal has slipped from the body. Usually what happens is that the
guitar gets too hot, the yellow glue creeps and the insert pulls out of the
neck slightly. Once the glue cures the joint is tight and so is the bolt but
the neck angle is now incorrect and the guitar will have a nice action.....
for bottleneck!

Louis

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- Louis Freilicher

Oh No! Not another learning experience!

If someone leaves a guitar in the car trunk in August there are many other things that will probably need fixing too. I'd just fix the neck along with all the other things that came unglued.

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Dave Rector
Rector Guitars

    Actually the insert can't pull out as it is a threaded insert. If the threaded insert was pulled there would be evidence of some kind of damage. I agree the wood may have shrank to give that appearnce.
    this is actuall a pretty stable joint though I personally use Dovetails.

I don't care for it myself. It really comes down more to ease of
manufacture, rather than a philosophy like Taylors which also includes
the all important ease of serviceability.

I recall Martin claiming somewhere that the bolt was essentially for
clamping while the white PVA was actually what secured the neck.       
That's Funny.
Sheer strength and creep resistance of PVA in a high tension mortise and
tenon.

I see bolts that have come loose fairly regularly, possibly from winter
drying that let the bolt just loose enough to wriggle out, or maybe they
just weren't tightened enough from the factory. Usually the neck is
pulling out and up by the time I see it, but occasionally the customer
catches it early by the mystery buzz of the washer rattling around. Martin
will typically cover this under warranty.

I've only had to remove a few necks that were still glued on, and the
good news is that you rarely need steam. When you loosen the bolt you
can almost always work the neck back and forth a few times and it comes
loose. For the rare case where I did use steam I just made an adapter for
my steamer that screws in to the neck insert, has a stopper that hits the
neck block to seal it off, and sets the depth of the steam holes right at
the bottom of the tenon. I think I've only had to use it once.

I suppose I'm a proponent of making a choice between glue or bolts at
the neck joint, but I don't like to see both. One of, if not the biggest
advantage with bolt on necks is servicability. Why leave the fastening
hardware so meager that you still require an adhesive? At this point I feel
that you are really not getting the benefits of either style of neck
attatchment.

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Eschew obfuscation, espouse elucidation.

I think (notice I said "I think,") that Martin also has a threaded insert on the dovetail jointed necks. I think it is just a manufacturing aid, and one use is to attach a handle during the finish process.