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Set Neck Joint Types?


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I played a friend's Les Paul the other day--I'm starting to plan a Gretsch Jet/ LP Jr. mongrel. I might even give making my own neck a go.

One thing I know though, is that I don't want a guitar as thick and heavy as an LP. And I wasn't all that comfortable playing up on the neck --the neck joint on the LP was just as bulky, or even bulkier--as my strat's.

So I'm wondering: are there any other set neck joint types out there that work?

I remember seeing guitars from a luthier who uses a V-shape for the heels of his set necks --and he eliminates the tenon.

I'm assuming you'd need some pretty sophisticated equipment to make a matching v-shape pocket and heel though. But perhaps it's possible to build a jig that could successfully route a V-shaped joint?

Meantime, if a scarf joint is strong enough to hold the head of a guitar on, why isn't it strong enough to use at the heel? (Especially if only the bottom is the scarf and the heel and pocket still have "walls" up near the fretboard).

I often talk about my Melody Maker --looking at that neck it looks like they did pretty much the same thing I did with my 350 project --they took what was basically a bolt-on neck, routed the sides into a tenon and set it in. The funny thing about the Melody Maker is that the tenon do NOT extend past the fretboard. I don't know if they're all like that, but mine's been going strong for 40 years.

I understand that this isn't considered the most stable joint though --but it seems to me that a similar joint in a single cutaway LP-style body would be a lot more stable, since there's a whole side, going up to the 16th fret to stabilize the neck.

Has anyone here experimented with other neck joints?

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I don't see the advantages to the 'V' joint. I think you mean the Brian Moore guitars (or was it John Suhr? One of those boutique super strat builders) that had a 'sloped sides' bolt on neck, two bolts only, which supposedly provided a tighter fit (and, I'd imagine, auto-centers the neck).

Re: scarf: it's often reinforced with a peghead veneer, and you treat the neck/body joint a good bit more roughly than you do the headstock. Well, most people do. Headstock joints are still an area that fairly often gets damaged. Besides, I don't see any advantage to a scarf at the body end compared to flat surfaces glue to each other, either structurally or in terms of reducing heel size.

There's also rigidity to think about. I want my neck to couple strongly with my body. No flex, nothing. And I do like to engineer my necks so that I'm sure they'll be solidly set. I don't much like most SG neck joints (and especially not the no-angle ones) because they aren't embedded into the body very well, and have a greater 'lever' action going on than a back angled neck that's set more strongly.

You can carve away a fair amount of heel, particularly on singlecuts. Look at some of David Myka's singlecuts, f'r instance. I do similar stuff on my own guitars, although to date those have been doublecuts, so that isn't going to help you overmuch.

You do not need the long tenon, that's true. But if you've got a neck pickup anyway, using one adds a little tiny bit of extra peace of mind, and doesn't make construction any more difficult.

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You do not need the long tenon, that's true. But if you've got a neck pickup anyway, using one adds a little tiny bit of extra peace of mind, and doesn't make construction any more difficult.

Yep, I'm looking at a single bridge pickup. Although I'll still have a pickguard (of course!) so a tenon could work. I'm just wondering about alternatives.

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There are only really two types of setneck joint - dovetail and tenon. The size and shape of the tenon is almost infinitely variable, but they all work the same way.

Cut the end of your neck to a shape of your choice (following necktaper, or parallel sided) and route a corresponding mortice in the body.

A scarf joint would be of very limited use for a neck joint, since this is an area which is subject to a levering force - and glue is less resistant to 'peel' than it is to 'shear' - the sides of the tenon do most of the work.

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idch,

There isn't anything instrinsically bulky about a tenon setneck. The implementation on a Les Paul is all based on tradition and retaining those aesthetics.

Remember xlr8's rosewood neck LP?

84bde136.jpg

The V-shape tenon might have been the Anderson Atom.

If you're worried about bulk, you could just take the bottom off of the standard set neck. Picture a neck-thru guitar. Instead of carrying it all the way through the guitar, just take it past the neck pickup you won't be installing.

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Yes, the Anderson joint, that's the one. Probably really difficult to pull off well.

I came across this one too:

Compression Set Captive Neck Joint

It's not a set neck, it's a bolt-on but it's an interesting idea. Might not be necessary for a true set neck (not really necessary for a bolt on either) --but I'm still planning to convert one of the necks I have here from bolt-on to set neck.

I'm wondering what the 'compression' part is about --does it mean he squeezes the neck into the pocket? :D

But adding a shelf like this would definitely help keep the neck in place. And it would create an even more complex series of glue points without being complicated to route (like those Anderson joints) ---one could add forward and rear 'shelves' -- adding two additional surfaces for the glue to grip to the woods (in my 350 there are five surfaces making glue to wood contact--adding this 'captive' idea would make that seven)

All of this will be moot when I start working on my own necks! But for now, I'm still in a learning phase about the rest of it...

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idch,

I think that compression joint is probably just hokum. Just parse it out.

The forces on the neck: string tension pulls the neck closer to the bridge; the offset of the strings to the bottom of the neck puts a prying load on the neck joint pulling the neck away at the tuner side and pushing it in on the bridge side; and the neck bolts pull the neck onto the body.

String tension pulls the neck away from that step in the neck pocket. So, in the string direction, it isn't doing anything.

The step machined in the neck and the neck pocket can either be a perfect fit, gapped on the front step, or gapped on the back step. If the fit's perfect or if there's a gap on the tuner side step, when you tighten the neck bolts it should behave just like a normal bolt-on neck. Material under the screw head is compressed... the volume of compressed material is actually a symmetric stacked pair of truncated cones (frustums). The material incompression would be identical for a normal bolt-on and the CSCNJ.

If there's a gap on the bridge side step, then the tuner side step gets loaded with additional compression when you tighten the neck bolts. This adds a little to the bending loads on the neck and body. Depending how much interference there is, some or all of it will go away when you string up the guitar and tune to pitch. The string pulls the the neck away from the body where that step is.

If the interference is big enough, there will be a compression load path there between the neck and body. You could do the same thing with a small chunk of shim, not bothering with machined surfaces.

I don't know that the little bit of compression buys you anything. If the neck has a tight fit with the pocket, there's probably more vibrational load transfer from the butt end of the neck on the pocket wall. String tension is pulling the neck and body together there. If you think of a thru-neck, from the nut to the bridge, the string tension has that column of wood primarily in compression and a bit of bending. For a bolt-on, the compression comes from the butt end of the neck or sheared across the neck bolts if there's any gap between the neck butt and the neck pocket.

They mention stability and resistance to shifting. Having a feature like that step would help keep the neck from twisting up or down (in playing position). But, if you had a tight neck pocket, that wouldn't be a problem.

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Hokum pokum...makes life fun, I say :D

I've been teaching my kids how to separate the advertising bullhockey from the product...

Anyway, here's another builder with his own set of ideas--

Veillette guitars

Can't get a direct link to his construction page--that's where you can get the details on his building techniques. Among other things you'll find:

A one-bolt neck joint

A wood bridge with a dovetail joint (it's ugly as hell though...)

Builders like this actually encourage me to question everything about guitar construction...

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