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Um, I wasn't thinking of putting the bolt in the end of the dovetail, I was actually thinking of a way to put it in the BOTTOM, so that it pulled the dovetail DOWN into the neck slot TIGHTER. Access to the bolt head is the only issue....but I can envisage a way to do it from INSIDE the git box.....

BTW, I thought Grit Laskin did the screwed dovetail joint first......from what I've read.....but I'm no expert on acoustic guitar history (yet).

Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

It might have been Grit....but of course that just adds another great luthier to the list of folks using the joint which doesn't <ahem> work.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I wouldn't argue that it doesn't work. My arguments are redundancy, uselessness, worst of both worlds - should I go on? In my opinion, either design alone is better than the two of them combined - like barbecued ribs and gelato.

I'm not saying that a better mousetrap can't be designed, but I don't think this is it.

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Eschew obfuscation, espouse elucidation.

Yeah, we had a long discussion about this a couple years back. Rick Turner and Grumpy both argued vehemently against it, not because it wouldn't work, but because they've tried just about everything out there and settled on using a butt joint. It's a very simple joint compared to either the M&T or the dovetail. I think what I like about the joint is that it takes some of the old school/traditional approach, and marries it to more modern technology, to some degree. There are customers out there that want a dovetail, but they can also be concerned about the high cost of a future neck reset. In the case of the bolted dovetail, you get the "best" of both worlds, not that either is completely ideal.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

What?!? Are you agreeing with me, Todd?!?

Fillipo, you make good points.

Ok, I'll give up trying to convince anyone. Rest assured though, I understand how a dovetail joint works.

And Don, why you gotta be pokin' at my bees, man?!?

I'll just say that I'm not going to be building any dovetail neck joints and then sticking bolts in them. My drawbored idea is much better. Not that I'm going to be doing that either. Well, maybe.

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Seems to me he's saying it can work...



They were. Didn't think about the thread thing...but I would think it was a combination of the wood not moving further, and then the threads locking. But then if this were a strong lock, there would be no need for locknuts.



Hmmmm......you sure? Then we can't draw out this battle of wits any longer.



Cuz....you said it won't work....and yet there are several elite level builders who use it and say that it does work, and that it doesn't do what you say it does. And I've seen it for myself. It isn't theory. Just trying to get you to think outside the box.



I think you should try it. It's unconventional, but people made M&T joints with tapered dowels for years. Of course, getting the thing *out* could be a bit tricky.....

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

A bolt on Dovetail is not a getting tighter with the bolt and is overkill. Yes you have the shoulders on the body but you will also have shrinkage over time. I tried one , and I do not see any advantage in fact you have , you will also include more mass in the hardware. If you want a bolt on neck use the M&T or dowels. Of course any builder is allowed to use what he or she wants. I can see that you have an idea that it may work for you so all I can say is try one. I don't think you will stay with it for long. Let us know
john hall

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

My last reply didn't go through so hopefully there won't be 2 here.

I'm no expert but..

My understanding is that a good dovetail joint does not need glue or a bolt. You should be able to string it up, play it etc. without glue or a bolt.

The glue (or bolt) seems to be for "peace of mind" that the joint won't fail rather than an integral part of the joint itself.

If thats true, why does it matter whether you use glue or a bolt? In fact, the bolt seems easier for removal of the neck later.

What am I missing here?

Alright, Williams, it's back on! I'm takin' the gloves off, pal. (I hope you can tell I'm messing around. I now how quickly a good debate can deteriorate into something else over the internet )



Well sure, it can work... if you do it completelty different from the method we're debating! That's been my whole point. When you fit a dovetail joint like this (a sliding tapered dovetail, that is), you don't push in to pop it together, you push down. So why would you put a bolt to pull it in?

The idea of making it drawbored is essentially the same as putting a bolt in the bottom. Either of those would work.

Now again, I'm not saying that putting a bolt in the way we're debating (like in my original drawing) would make the joint not work. I'm just saying it defeats the purpose of a dovetail joint. In my strong opinion, you lose the benefits of the mechanical dovetail, whilst gaining the benefits of a bolted-on butt joint.




You're right. This hasn't been drawn out nearly long enough





Sorry, Don. I was just having a little fun here. Please poke at my bees all you want. Ain't afraid of no box or nothin.



[qoute="Don Williams"] I think you should try it. It's unconventional, but people made M&T joints with tapered dowels for years. Of course, getting the thing *out* could be a bit tricky.....

[/quote]

Honestly, I'm more intereseted in playing with an adjustable neck joint right now. But I may in the future. You're right about getting it out. It would need some type of handle.

Cheers

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

A dovetail joint will hold together just fine without glue under tension, but not over time. I string up and play every neck reset I do with a dry joint before gluing it up, but they do need to be glued in the end. You can't reasonably expect a dry dovetail joint to handle seasons, shipping, bouncing around on stage on a strap, etc., without being fastened in place. The dovetail is the structural geometry, bit it still needs something to keep it from sliding apart (and ripping off the extension as it goes). Just a little bead of glue on each side of the dovetail is all you need, and it's not that big of a deal to take apart.

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Eschew obfuscation, espouse elucidation.

Addendum to above post:

So the goal in the dovetail is to allow it to hold the system together, but you still have to keep it from sliding or being jostled apart. In adding a bolt to a well fit dovetail, you could be increasing pressure on the outside while lessening it on the inside of the joint - assuming the joint is well fit, you should not be able to notably increase the sum friction by adding a screw. You would be putting a pin in like Mike's drawing above, only threaded. Though the sheer strength of the pin or screw is probably fine, the compression strength of the woods is the weakness. A good whack or a slow creep to slide the joint upward, and the bolt would just tilt up at an angle, compressing any wood in it's way. This can be lessened by mating the end of the dovetail tighter, but now your making it sooooo much more complicated than it needs to be, and making neck resets harder than a glued on dovetail.

Rather than asking "If a bolt allows for easy removal, why bother with glue?", you should be asking "If we can use a bolt, what possible advantage does complicating it with a dovetail offer?".

The dovetail neck joint is a long cherished child of luthiers, and this is an example of some parents trying to let the air out of the tires when it's about to leave. Some have just barely been able to budge far enough to accept a metal fastener , but they just can't let the dovetail go yet, so a creative way is sought to keep it involved and almost make it seem to make sense.

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Eschew obfuscation, espouse elucidation.

Thanks David for that well thought out answer. That all makes perfect sense.

I can't say whether I'm in the bolt on camp or the dovetail camp because I don't have any "sound" data (pun intended) as to which way (if either) has an effect on tone.

However, I do like your quote below (hopefully the dovetail camp can laugh at that as well):

[quote="David Collins"]Addendum

The dovetail neck joint is a long cherished child of luthiers, and this is an example of some parents trying to let the air out of the tires when it's about to leave.

One additional thought: On a normal M&T bolt on, you would generally use 2 bolts. If you were to make the dovetail bolt-on workable I would think you could get away with one bolt, thus reducing the weight. And the debate goes on...

Hey Mike...no, I'm not taking any offense whatsoever...and hope you're not either. I kinda like these discourses. It makes us all think.
The tpe of dovetail joint you have to use is an interference fit, not a sliding fit. And yes, I meant down, not in....but that's a matter of perspective. One could easily say you puch the dovetail down into the pocket...

It would have to be a very tight ft for this joint to work without releasing the pressure on the dovetail. That's what is needed.

I gotta go for now....but more arguing later!!!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Sam, thanks for making note of it, and I should say as well that yes, the "child leaving home" metaphor was meant as a light-hearted poke in the ribs.

Two more brief notes. First, as a repair person I do see the occasional bolt on neck (both butt and M&T) creep upward on occasion. Not so often as to declare the joint entirely faulty, but it may have slightly lower tolerances to seasonal humidity changes or heavy jostling. I do find loose screws (and loose tenons) fairly often on the single screw Martin "screwed and glued" neck joints - usually following periods where the instruments have dried out, allowing the screw to slacken enough to vibrate loose.

Second, I feel the weight debate needs to be thought through a bit more. Of course we associate lighter guitars with a more desirable tone for many. I think it's important to see it as a correlation on the whole though, and not take it as a rule that every point on a guitar needs to be lightened for optimal results. When an instrument sounds great because perhaps the tops, or bridges, or maybe necks are very light, or sides are thin and flexible, etc., the cause/effect relationship deserves some scrutiny. It may very well be that the lower mass and lower stiffness in some areas yield great results, but does not require that all areas need to share those traits to get what you want. It could very well be that a point like the neck joint could add benefits by having greater mass and inertia than other more active areas. I'm not saying I'm sure that it would, just that it deserves a bit more focused thought and consideration.

"Building light" I feel can be taken to extremes, and needs to be thought through point-by-point. Always be weary of the "If this recipe calls for one teaspoon of salt, it will be twice as good if I add two!" kind of thought.

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Eschew obfuscation, espouse elucidation.

I agree on bolt on necks being more sensitive to seasonal changes. I use the Cumpiano
fixation system with a bolt on fretboard tenon . I always tell owners to check the tightness of the bolts after the first winter. A lot of them get a little loose as the guitar drys out. (Tuner screws as well) Seems like after a year or two that is not as big a problem.
David, (or anybody) what's your take on why new guitars are much more sensitive to seasonal change and seem to stabilize after a couple of years?
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Very cool. No offense here either, and I'm enjoying it as well. I just worry sometimes that my humor doesn't come accross that well over the interweb.

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Wait a second. What is this little nugget I passed over earlier???!?!?

David, I might be reading this wrong, but this sounds dangerously close to being exactly what I've been trying to say this whole time. Am I reading that correctly?!?

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Yes, Mike, I think I actually agree with your appraisal completely. While pulling inward with a bolt or screw on a well fit dovetail should not cause movement or separation of the dovetail, it could shift pressure away from the dovetail surfaces and add to the heel/shoulder joint. My thoughts are that the sum pressure would remain near equal, but shift the balance a bit. I think phrasing is very key in making the argument though. Arguing movement of the joint could be iffy, but a shift in pressure does not require a shift in position.

And just one more thing. With a topic and arguments like this there have been so many opportunities to draw blood. This thread has gone from tolerant to downright cordial. This crew is just getting soft......

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Eschew obfuscation, espouse elucidation.

Well said, David. I suppose I could have been slightly overdramatic in providing an absolute worst-case scenario where the bolt is cranked as hard as possible and the wood is on the soft side.



Kinda makes you miss Mario and Rick, doesn't it?

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger