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Ok guys, going back to how a dovetail works...
..or how I perceive it to work :

1. As the dovetail joint is slid together, not only does it tighten against itself, but if done correctly,
it also tightens up the cheeks against the sides of the guitar does it not?

2. If therefore when it is fully engaged and locked into itself,
and both the angled surfaces of the joint are in contact, and the cheeks of the neck heel are in tight contact with the sides,
how the heck can it be drawn into into the body farther as Todd's drawing suggests????
That is a physical impossibility, unless as I said, the fibers on the heel and body are compressed in the process.
You guys are thinking that since there's a gap behind the dovetail, that it can move in that direction,
which it can't because the cheeks of the heel prevent it from moving in that direction, unless it moves upward also.
It can't move backward any more than it can move forward.
You can't negate the front part of the joint from your argument and say that it will move. AS I said, you have to look at the whole unit and not just a part of it.
If there are no heel cheeks, of course it can move.

A perfectly fitted dovetail does several things:
It aligns itself.
It aligns the top of the neck perfectly to the top.
It draws itself inward and draws the heel up against the sides.
Right?

Maybe I'm just dense...but my logic seems correct.
Don Williams38806.6064351852

_________________
"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."

Why make it all so difficult? What is the advantage of the dovetail?   Is this an intellectual excercise or a tour de force in craftsmanship, or is it way to make a better guitar that is easily repaired in the future? I get the sense that the love for dovetailed neck joints is more of an emotional bond to a romantic past than good modern engineering.

If you tighten the bolts you will get some compression of the wood fibers. The joint probably won't pull apart but the pressure on the face of the dovetail will drop. You probably won't lose alignment either which is why other builders have used it successfully.

Suppose that you didn't get any compression of the wood fibers. Then, what function is the bolt doing? The only degree of freedom that is not locked in in a dove tail is the lifting of the neck. The pressure supplied by the bolt is at 90 degress to the direction of motion.

I suppose that a well fit dovetail joint doesn't need to be glued at all once the fretboard extension is glued down. That will prevent the neck from lifting.

It draws itself inward and draws the heel up against the sides.

Correct, but once you introduce a bolt, you'll pull the heel tighter into the side, and the dovetail away from itself, even if it can't be measured. But the fact remains, you've now put the neck's torque onto the bolts and the heel/body fit, and away from the dovetail to neck block fit, so why bother with that part of the equation?

I love the idea of the tapered washer thingie. I've long thought that if I were to go back to dovetailed necks(I used them for a year's worth of guitars in '99-'00) I'd come up with a cam system or something. There it is.... The elongated heel cap would work, but it would be a bugger to fit nicely(the cap), and iot would not look "traditional" for those of us in a market that asks for that look.

But my customer base is happy with my neck present neck joint, and I have no need to fix what ain't broke. I guys, this joint ain't my idea for a long shot; I took it, part for part, from the early Taylor guitars. If the joint was weak, Bob would have used something else. They're not big fans of warranty work, I'm sure.

Don one last practical consideration (sorry to pile on here), but dovetails often don't perfectly aligned even with accurate jigs. It's a whole lot easier to perfectly align a square tenon than a dovetail tenon with the old sandpaper between the rib and heel trick. Try doing that with a snug dovetail joint -- it ain't fun. Also its easier to trim the cheeks of a square tenon than a dovetail tenon. [Now that I think about what Mario said earlier -- I am wondering why even bother with a bolt-on/tenon combination].

So at the end of the day -- what have you gained by bolting/screwing in a dovetail? (Nada)

Tony Karol has been telling me for years "why bother introducing all those additional operations."   

The only reason I use a dovetail joint is because I build archtops and don't have the luxury of a 4" soundhole. Someday I'll get a welder to make me up a 25-inch long allen key wrench so I can bolt'em on from the end pin hole    Revelation -- loose the tenon and it'll be a whole lot easier to fit the neck extension!

Don I would have never thought of this if it wasn't for your _____ dovetail idea Anthony Z38806.6963888889

[quote=Super Mario]Correct, but once you introduce a bolt, you'll pull the heel tighter into the side, and the dovetail away from itself, even if it can't be measured.[/quote]

So you guys are saying that even the most minimal pressure of the cheeks being drawn against
the sides with force greater than the dovetail provides can release the friction fit of the dovetail components then, right?
I think I get it. I think I would have to experience it to fully understand, but I get it.

But...please indulge me for one more moment... is this real or is this theoretical on your part...you guys who are making this argument?
I ask, because if nobody here has actually tried it to see....then one theory is as good as another until either are proven.
I tend to think in absolutes, and also from a machining background instead of a woodworking background.
I used to work on designs for injection molds, and frequently we had parts that were "dovetailed" to some degree, which were secured by bolts and never moved. Ya I know, apples and kiwi fruit.

Mario,
This whole discussion was started because I was seriously contemplating this idea of trying it, and although I'd never done it, I felt I had the theory down in my mind pretty good. The arguments posed against it seemed illogical, based on my theoretical mental model.
I'm not at all hung up on the "traditional methods" as most of you know. But I was seeking to find a blend of the more traditional and the modern, that would hopefully appeal to a wider range of potential clients.
(Of course I'm retired, so... )
Anyway, I'm now quite fascinated by the fact that you seem to have a cult-like following amongst traditional bluegrass players, even with a non-traditional neck joint. Perhaps what I've been told about buyers looking for traditional workmanship is more hooey than what I've been lead to believe....
Thanks for putting up with my pressing to get a better understanding and to some degree playing devil's advocate against the devil's advocates....


Don Williams38806.7010648148

_________________
"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."

It's no big deal to make a long Allen wrench...without welding.   Just drill an appropriate sized reasonably tight fitting hole in the end of a piece of steel rod, cut off the right Allen wrench section, insert it into the hole and hammer the rod around the Allen wrench. Then flood the thing with superglue.   Put a handle on the other end of the rod, drill a hole clear through the handle and the rod and cross pin the handle to the rod.   What's that? About 15 minutes, that's what, and that's if you have to go searching for the superglue.

That's how we put the necks on our ukes, and it's how I did a carved F hole mando guitar a number of years ago. I love easy.

Rick -- great idea! Sorry to go off topic (we'll return to abusing Don in a sec). When you did your mando guitars did you do them without a tenon?

So you guys are saying that even that the most minimal pressure of the cheeks being drawn against the sides with ....can release the friction fit....

YES

....is this real or theoretical on your part.....

Don, I just got back from the shop where I've got two dovetail examples in the white. If I push slightly on the bottom of the heel towards the rib I can feel the neck wiggle a bit. The reason is the tension between the cheeks of the dovetail and the mortise is reduced. Now if I had a bolt insert and snugged it the wiggle would go away. If the neck got whacked from the side my alignment might go off a smidge. With a well fit simple tenon or as Mario and Rick do it -- the same thing wouldn't happen.

Don this post has been great for me -- it forced me to rethink some things I have been doing and change what I planned to do on some upcoming flattops! Thanks!

. Perhaps what I've been told about buyers looking for traditional workmanship is more hooey than what I've been lead to believe....

Yup. Who's left making dovetails now? About half of the Martins, and Santa Cruz.

Collings, Bourgeois, Huss & Dalton, Rockbridge, etc.. are all bolted. It's actually a selling point now, sicne everyone now understands that neck resets are inevitable, and the players are also now very hip to the fact that they don't have to see their saddle dissapear and their volume and tone suffer in order to lower their action a bit. They know that with a bolt-on neck, their setup person of choice can just reset the enck in 15 minutes and they'll have low action, and retain their original saddle height.

Gone are the days when players put up with poor setups because they came from the factory that way, and they couldn't see how to adjust anything(non-adjustable truss rods and glued-in saddles didn't leave a lot of room for tweaking a setup easily <bg>). Nope, today's players are up to date on how to maintain their guitars.

About the only folks left who still think they have to have a dovetail are folks you don't want to build for, anyway, trust me.

[QUOTE=Mario]
About the only folks left who still think they have to have a dovetail are folks you don't want to build for, anyway, trust me.[/QUOTE]

Roger that...


I'm still going to try it, mainly because it can't hurt to acquire the skills to set a dovetail, which obviously can help you reset them if you do some repair work. I may break down and try one of them funky butt-joint ones eventually too, although I suspect the learning curve is a little shorter on that one.

_________________
"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'm sure this falls into the category of "why bother", but if you were to make a simple dovetail rather than a compound dovetail, the bolt wouldn't be working against the joint, right?

Andrew Wright
Managua, Nicaragua

In the cabinet biz, that's known as a sliding dovetail, and once again, why bother?   I see a lot of people going for the most complicated of solutions dreaming that because it's difficult or traditional, it must be better.   Our ears tell us that there is no discernable advantage to a dovetail jointed neck.   At least most people have agreed on this, and many who had believed in the sonic superiority of dovetails have had to eat crow when they realize that, for instance, a Collings has a bolt on neck. If you build steel string guitars, they will need a neck reset someday.   Make life easy on the repair luthiers of the future or you may come back as one and have to repair your own work 50 years from now!

I was just playing one of my 100 year old Howe Ormes last night and marvelling at how great it sounds...and at the fact that I can raise or lower the action with an 8 penny nail to turn the capstan bolts in about 10 seconds. This guitar is as much fun to play as anything I've played in my life...and it has a bolt-on neck and cantilevered fingerboard.   The neck attachment has less than 1/4 square inch of contact between the hardware in the heel and the body.   Nothing is lost tonally in this system, nothing. It's the best ladder braced guitar I've ever played, and it's got low end for days and beautiful sustain.   Martin Simpson declared this instrument to be one of the best three guitars he'd ever played, and I'll go for that kind of opinion any day of the week re. bolt-on necks.   Martin usually plays a Spanish heel guitar...as per Stefan Sobell, so that's where that opinion is coming from...

I build almost exclusively classicals so I can not speak as well to the dovetail (although Fleta and a couple others used that joint). I build in the traditional Spanish style (spanish foot) but with the modification introduced by Romanillos.

Romanillos uses a method in which instead of the neck block being slotted and the sides glued into that slot as is traditional with classicals he makes a larger tapered slot in the neckblock and then uses a tapered wedge to hold the sides in. In this way a classical guitar which is usually built face down on a workboard can be still using the spanish method but later if the neck has to be reset it is easy to adjust.

Thomas Humphrey uses a bolt-on butt joint neck and doesnt apologize for it.

I know it isnt dovetail versus screwed butt joint but it shows there are different ways to easily do a nack that can be built quickly and still be easily serviced.

The Lutes I built instead of a screw as Colin mentioned I used a handcut (not smooth) nail to attach the neck to the body. This is how Stradivarius and other violin family builders have done for centuries. Guitar builders as late as Gennaro Fabricatore used a nailed butt joint to body method for their guitars and they have held up well. It is simple and effective and as Mario said, "use a mortise and tenon if it helps you to sleep".

Regarding Rick's Howe Orme's Adjustable action...it is so sexy to play an adjustable action guitar. I have 19th century French (LaCote) and Viennese (Stauffer school) guitars with adjustable necks and they are a blast to play...change the action for the style of music and playing and in an instant the guitar feels and plays different.

I have never built a guitar with adjustable action like that but if I built a steel string would have to use a bolt-on butt joint neck ala Rick and Mario.Shawn38806.876087963

Anthony, yes, the mando guitar which is on page 101 of Acoustic Guitar Magazine's "Custom Guitars" book, is a straight two bolt butt joint.   I made that one in 1998, and I haven't heard a peep out of the customer other than that the instrument sounds just fine.   The body was a miniature (12") version of a '34 Super 400, and the photo is amusing because you get no idea of just how small that guitar is.   It's got six single courses tuned in 5ths and a fanned fretboard.   Someday I'll have to build myself one; that little baby was sweet. I really wrestled with buying the customer out on the thing!   No, not a good policy, but that instrument is one of the coolest ones I've ever built.   

[QUOTE=ToddStock] This has been a pretty good discussion, made more so by the design ideas and the civility - try having this debate over on a Martin-oriented forum.
[/QUOTE]

Yikes! I know some Martin fanatics are staunch traditionalists for sure. I like discussions like this because it pushes peope into thinking things through and gets the gray matter electrons moving for new innovations and ideas. I like challenging perceived notions and dogmatic opinions. I learn, and hopefully others do somehow too.
If everyone accepted the "because this is the best way to do it" argument, there would never be any new innovations that could change things for the better.
I say let's all switch to Banjo style necks, and then the discussion is moot !

Don Williams38807.4250694444

_________________
"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."

Okay, it's more than obvious that there are those that have no interest in using the dovetail anymore. Though I understand some of the issues some have had with a laterally drawn dovetail, I still can't understand why the idea of essentially a "quick-release" dovetail, which seems to be Don's objective here, comes up against so much resistance. Maybe it's because I was considering giving it a try someday as well. You're not alone in this cold world, Don! I say forge ahead!!

_________________
DES - Shepherd, MI

The 'Quick release" dovetail would be cool, in my book. As long as you do it in a way that draws the dovetail tight and not loose, such as can be done withy the bottom screw or the tapered washer/cam thingie.

When the labor to fit the dovetail, plus the disadvantages on neck resets, etc. are taken into account,

Actually, once you're well jigged and the jigs have been fine tuned, nothing's faster than a dovetail. It's all woodwork, and can be done with one router and one bit. Set the router up, and never touch it again, and you can cut both teh enck and body in a minute and have it fit to near perfection, needing only a couple swipes of sandpaper of each heel to fit them to the body. Why do you think the cheapest of the cheap guitars coming out of the far East are fixed neck guitars?

Bolts require a jig to drill the holes for the inserts/barrels/studs, another for the body's holes, they neck block needs to be couter-bored to recess the bolt heads, then in fitting, the botls need to be snugged-up, then tightened. All hand work. In a factory setting, the dovetail rules the speed charts.

The real advantage of the bolt system is repairability. While we now know how to take a dovetail apart with minimal intrusion, blow outs still happen every now and then. Steam and heat can and will often loosen other joints in the process. In contrast, I could probably coach half my clients, over the phone, to reset their neck on the kitchen table with few tools...(not that I will, though <g>)

So, Mario, do I have your permission to patent my interior bolt design with your dubbed "tapered washer/cam thingie"?

_________________
DES - Shepherd, MI

That diagram of string tension directions sort of looks like a twisted swastika... You neck nazis are confusing me. I think I'll just go hang myself by the necktie. Actually it's funny but I really had this same idea a few months back and realized I was probably just a novice trying to reinvent the wheel or bulletproof a toaster. It seems to me that a screw or bolt in a dovetail might sooner or later facilitate cracking in undesirable places. Another thing that comes to mind is that screwing into end grain is an inherently weak joint. I learned this in Carpenter apprentice school. I lean towards the idea of using time proven joinery that maximizes wood to wood contact, but then I've never had to reset a neck.   

   At the risk of sounding like a complete idiot on april fools day, I must say I've never done a dovetail neck joint anyway. I am just a novice learning to build my first acoustic. The tradition and challenge of doing a dovetail always sold me on its superiority. I know one thing though: You don't need to make a joint stronger than the material it holds. I respect Rick Turner's views because of his experience. He seems to imply the sound of an acoustic comes not from a neck vibrating a body, but rather from strings that cause a top to vibrate and be amplified by a box. In other words a constant tight wood to wood joint is not even an important tone consideration because the neck effectually causes no important sound transfer. Excuse me if I ramble... But I always thought ideal tone would come from having everything fit together as tightly as if it were made of one piece of wood...
   
It's been great learning from you guys. The only neck I've installed was one I found in a dumpster outside the G&L factory in Fullerton California. It was hard enough just setting that one. nickton38808.2645601852

_________________
"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

Don't get my point wrong here, please!   In fact there is very, very good solid contact between the neck and the body on the Howe-Orme or my own adjustable bolt-on system.   It's just not a lot of surface contact. Think of it like a three legged "milk-maid's" stool which makes very solid contact with just about any kind of rough floor in the barn. Three points of contact...very good geometry, and almost impossible to get it wrong.   Why do you think photographers use "tripods"?   Because it provides solid contact.

All that said, I'm not so sure that there's a hell of a lot of useful transfer of string vibration from a neck into a guitar body. I think most of that may be "and old wives' tale". That is not to say that there is no transfer of energy, but it's as likely to be out of phase vibrational energy as in phase. Thus those vibrations may be killing tone and sustain as much as adding to it.   

I can tell you this, I recently played "Miss Antarctica" after not seeing that guitar for more than a year, and I was blown away and actually surprised at how good that guitar sounds. Nobody would ever guess in a blind listening that there's so little contact between neck and body. It's loud, full of harmonics, and sustains beautifully.

Another interesting point is that when you play notes on the cantilevered section of the fingerboard where there's no direct contact between fingerboard and top, the notes sound just as strong as playing anywhere else on the fingerboard. That surprised me and taught me more.   But think of how a violin works...notes up on the fingerboard extension sound fine.   Speaking of which, violin family necks aren't dovetailed. They're essentially mortised butt joints...without a hell of a lot of contact on the sides of the joint.

Regarding wood to wood contact at the neck joint, it's one of those things that seems right, so you don't question it. Well, question it and question everything or risk not understanding anything.

I'm one who believes there is plenty of energy to be had from the neck. But I don't belive the neck joint matters, because, as Rick says, solid is what solid is, and a solid joint of any making will let energy through. My argument is always to keep the upper bout of the body free and light so that the enck's energy won't get lost, and this is where Rick has us all beat.

Interesting. I've always thought that necks waste energy, in that the more stiff it is, the less energy is absorbed into it while more ends up at the bridge. That's why so many folks use laminated necks and carbon fiber to stiffen them right? Seems to me that you want the neck /body joint as stiff as possible too so that the energy isn't wasted into the sides and the stiff part of the upper bout.
Unless of course you're saying that the vibration of the neck from the strings in some way *adds* to the product, in a synergistic kind of way??????

_________________
"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."

Hmmmm... I always thought a primary reason for increasing neck stiffness was to raise the resonant frequency high enough to keep it from potentially interfering with the notes played.

Kevin Thomas
Quail Rock Guitars
Austin, Texas

Sure, I make my necks good and solid, too. But no matter how solid you make them, the strings will still shake the neck some. The string doesn't care which end moves, the tuner of the bridge pin look the same to the string. By making a stiff , solid neck and a nice and light top, we ensure that most of the energy will go to the top, but no matter how hard we try, some will still be in the neck. Otherwise, my Intellitouch tuner wouldn't work <bg>

So, as longa s its there, may as well put it to use, and get it into the top, and not let it go to waste.

This is always the argument the dovetail guys use, and it is why I built with dovetails for a year. I then compared that years' worth of guitars to the previous years, and the following years'. Nothing i could poinht to said that one neck joint or the other lent anything to the sound. But I did learn that with an ill-fitting neck, much was lost. In the end, my findings were that if the joint is solid, it is good, and that is what counted.

[quote=The Mario]In the end, my findings were that if the joint is solid, it is good, and that is what counted. [/quote]

And that would seem to be the bottom line.
So keeping my options open, I'm going to try a few dovetails, maybe bolt them or not, and a few like what Mario does now. I guess the only way to really get an idea what will work for you is to try the available options. No sense not trying everything.

Thanks everyone...

_________________
"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."