Official Luthiers Forum!

I do repairs for a living and have also seen quite a few dovetail failures come through the shop needing work.

Whoever says ANY neck joint is bulletproof doesn't know what they're talking about.

I haven't seen many bolt neck failures, nor any bolts come loose ever.

I attribute that to the fact that most bolt-neckers use some kind of thread lock,

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Old growth, shmold growth!

Of all the dovetails I have seen fail most were stressed or had a glue failure. I agree no joint is bullet proof. If you haven't seen a loose bolt you havn't looked hard enough. This is a known fact on Martins.
Lets looks and agree on a few points.
NOT ALL BOLT ON JOINTS ARE THE SAME.
Martin used 1 bolt and relied on glue
this one is a known failure.

There are bolt on joints that use 2 bolts and no glue but glue the extension

there are joints like Taylor that bolt the extension and main joint

then there are the bolt on neck joint that the extension is part of the neck itself.

they all have their strength and weakness.

If I had to rate them from experience I would rate the single bolt glue joint the most unreliable
The true bolt on with the extension supported by the neck one of the best.

2 bolts are much better than 1 and steel bolts better than brass.

When glue is involved the block grain orientation is also important.

there are different styles of hardware to attach the bolt threaded inserts , barrle inserts etc.

Is there a perfect neck joint NO

Is there one better than another ? A good design , is that , a good design.

If one is looking for weight , the dovetail is the lightest design. The neck blocks are also part of this .
Sylvan Wells used a well designed bolt on neck.
I know he helped many down in Todd's area and I assume they are using a similar design.

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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

lets us agree that it comes down to design and craftsmanship.
there are some good designs out there but poor workmanship will make it useless. that works both ways in dovetail and bolt on.
as for bolt on I know I would not use a martin design. The design I do use is a double bolt with a threaded insert and a glued on extension.
The only reason I like this one over the others is that is has less weight than say a Taylor design. Todd brings up good points about the wood choices and grain orientation.

The end result is simple the neck says on and holds the stress. If the workmanship is inadequate no design will work. Joint integrity is as important as design.

I think we can agree that the 1 bolt glued neck is inferior to all 2 bolt designs. Personally a good bolt on won't need glue. In all cases the joints have to be stronger than the stresses applied.

In all cases there are the mechanics and engineering of the joint. It is hard sometimes to close the door to the opinion we form and discern the facts involved .

May we all agree to disagree without being disagreeable. After all reading a sentence if often different from hearing it spoken.

If I had the opportunity and time to experiment on a joint , here is what I would like to see. My toolmaker and machinist back ground would make it a 3 point connection. I think I had seen a similar design a long time ago No joint but 3 studs coming out of the neck block. There would be 2 cups on the upper heel that would fit on the 2 studs coming out of the block. These would be adjustable to set the centerline angle and can be adjusted but a jam nut but the string tension would hold this on. Intonation adjustments would also be done as you could in all intents adjust the compensation length of the neck to the saddle.

on the bottom of the heel would be a stud that is connected to the neck and secure. This would penetrate the neck block. The threaded stud would be captured by a barrel nut in the neck block and can be locked with a jam nut on the heel side. This would allow you to adjust the neck angle without a lot of work.

The extension would have to be made to be part of the neck and pocketed to the top of the guitar.

there have been many adjustable neck joint through the years. For all I know it most likely has been done before.

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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

A little like this one? http://www.frets.com/FretsPages/Museum/ ... aiser.html

that is it
you have a lot of adjustability but it is as non traditional as it can be

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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

That 12 string dovetail failure had a poplar neck, the wood is soft enough that it could compress to cause the lifting issue... not much I could do about it except to patch what was missing and reglue it.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

There you go. Now if that was a glued joint you wouldn't be able to get away with gaps like that.

Not much to add to the discussion, but I've had the pleasure of sitting down in Rick's shop and playing this guitar. Pleasure being the key word. Rick's guitars aren't light, but they're loud and ballsy.

Filippo Morelli,
I had my say yesterday and wasnt going to add anything to it but you called me stupid. This kind of attitude has no place on this forum. We are all giving our opinions as we would if we were at a coffee shop talking guitars. Keep it nice.

itswednesday14 wrote:
I love a light guitar. A little here and a little there and a little off the neck joint and you can shave a pound off the weight of the guitar. So plus one for the dovetail.

1oz≠1lb....not even close being that your statement is a 93.75% error....fits into my definition of asinine...

sure, everyone has a right to an opinion, but when facts clearly demonstrate the error of said opinion then said statement should be called out so that others don't spread such errors around...

AFAIC your overbearing politically correct way of acting (as demonstrated by your instigating the situation then going and crying to mommy about it all) is what doesn't belong on this forum or in real life...in fact I am getting rather sick of people creating situations then blaming those that rightfully respond with the truth

The Martin Mortice and Tenon joint is a poor example to use in this discussion about bolt on necks.
As far as I am aware it is considered a glued mortice and tenon with the bolt there merely as an assembly aid.

As Todd has said, there is often a fairly wide tolerance and thick glue line which is prone to failure.
That is the problem rather than the single bolt, which is not in this case intended to hold long term load.

In terms of resisting string load, the upper bolt in a double bolt joint actually does very little anyhow.

To be fair, he didn't say the neck hardware could increase or decrease the weight of the instrument by a pound; he said that a little here and a little there adds up collectively. If you believe in building as lightly as possible, even shaving 8 oz. off a four pound instrument could be significant. In that case, shaving an once could be a "material" concern.

On the other hand (goes without saying), not everyone believes in building light.

there are 2 schools emerging , those that love bolt on,s and those that don't.

At this point I see this thread starting to get personal and I can no longer participate.

Many beginners that get into this hobby are exposed to the Martin neck , and that is a fact. Many assume this is what a bolt on is , and we all know different. There are many methods some good some not good and from an engineering stand point that 2nd bolt does indeed carry load and in many ways can carry the load very well.

goodbye

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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

Actually from a true engineering standpoint, the bolt furthest from the strings is the one which takes the vast majority of the load from string tension, Once the fretboard extension is glued, the upper bolt could be removed without harm.

I've used both but mostly the Cumpiano type M&T with a reinforced tenon and a bolt on fretboard extension. Probably close to 50. It's uncommon but the bolts can loosen if the guitar gets dry. I've seen it happen. I'm not sure Loctite is a good idea as the loosening seems to come from shrinking of the head block rather than the bolt backing out and a thread adhesive would not help that. Anyone out there using something like a Belleville washer on their bolt-ons?

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

I had no idea neck joints was such a controversial topic, I thought this type of "heat" was reserved for discussions about glues and finishes... Stick around John, I don't think anyone tried to attack you personally.

Actually, I'm not surprised of the OP's question. There are lots of unsupported theories, old wives tales and speculation regarding neck joints out there, including claims of acoustic superiority of one type of joint over another. Check out K. Yiari's web site http://www.yairi-france.com/#/dovetail-neck-joint/3113409 "...But the truth is that a bolt on neck does not transmit the sting vibration in the same way. It just sounds dead and disconnected from the body." There are others.

I usually use a barrel nuts and bolts, but I've done some dovetails too. In my experience they are more fiddly when you use mostly hand tools, but in a more industrialized setting, I'm not sure they necessarily are more work. There must be millions of various brands of Asian steel string guitars with dovetail neck joints, many of them unfortunately glued in with epoxy or some mystery glue, so they can be quite difficult to disassemble neatly. So can some of the American ones, for example a straight '70's Gibson type joint can be significantly more difficult than a traditional Martin joint.

Neck bolts can certainly come lose, that is in fact a pretty common problem with some of the guitars I've had in for repairs. It might have something to do with the climate up here; humid summers, dry, cold winters, which leads to a lot of wood movement. Its a lot easier to fix than a lose dovetail joint, though...

I'm not too concerned with the weight of the neck joint hardware, after all it is placed in a very rigid part of the instrument, so I don't believe it does much for the sound one way or another. Since it is also pretty much in the middle of the guitar, it has minimal effect on its physical balance, whereas a similar change in weight at the far end of the neck can be felt, which is one reason I'm more concerned with the weight of tuners.

Now, if you want a real challenge, try a compound dovetail on a F5 mandolin sometime. Its a very functional and beautiful thing when it done right, but boy, talk about nightmare to fit! Thankfully, there are alternatives, which may not be as "traditionally correct", but they are easier to fit, and equally strong.

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Rian Gitar og Mandolin

K. Yari needs to look at a Collings neck heel....not so big and bulky, and a bolt on...can be done.

FWIW... I used to use a dovetail exclusively, I have no problem producing and fitting and actually like the joint. I just don't like the idea of one of my guitars coming back with say a twisted neck (or something else out of my control) that will need to be removed and most likely replaced. The removal part is why I switched to a total bolt on, totally eliminating any steam and other tooling damage to the body. All loses are isolated to the neck.

Chuck

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I don't have much to add here,
but the one bolt on I did was more of a pain than a dovetail.
I like fitting a dt until it's nice and snug.
As to the original question about tone,
I think most of us agree that it doesn't make any difference.
Look at the git in my avatar.
Mahog neck, laminated wings where it is glued to the sides,
kind of like a spanish heel.
Not finished yet,
but I don't think it's going to move!

There's a video of the Hofner factory, showing their straight M&T (sorta) neckjoint on the violin basses; these are notorious for failing. I would never trust an M&T neckjoint sans hardware.

Sliding dovetails are excellent 19th century joints. Thank God--and Bob Taylor--for helping to drag luthierie, kicking and screaming, into the light...(insert wink emoticon).

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https://soundcloud.com/jeffreylsuits/he ... -runnin-13

Play nicely!

Before I started dabbling in these dark arts, as a player of 30 years+ I was what you would call a traditionalist - Bolt ons? Bah, surely the cheap option and a sign of the unskilled... I believed much of the hype surrounding 'effect on tone' and felt that an expensive quality instrument must have a dovetail...

But as with many on here, once you start actually reading up and learning about these things, you get an insight that is often not available to the player- to me it's clear that if you strip out the mystique and BS, it comes down to a simple issue. You have good and bad joints.... There are several ways to get the job done, each with pros and cons, and maybe the 'perfect' neck joint has yet to be discovered - indeed it's interesting to see new ideas on this, whether Bolted, glued, wedged, or a combination.

I like the idea of being able to craft a decent dovetail - purely to try and hone this skill, but I also like the idea of a more rapid and easier removal that comes with bolts and the advantage this has on tweaks etc in later years....

I think the only question we should probably be asking is; How can I give the player/eventual owner the best possible service. For some that will mean the desire for a traditional approach to construction, for others a recognition that with heavy use and abuse, the easier neck removal will win out. In a way, if you can master a good joint whatever type, is the answer not to provide customers with choice same as tone woods, or level of bling?

Yes, and no. If one believes both joints are equal in terms of pros and cons then yes. Offer both and let the customer choose what suits their needs. But then there are those who prefer one neck joint over the other. For instance those that believe the dovetail is superior due to the fact it can stand on its own without the weight of fasteners blah blah. And those who say a bolted neck is superior due to X, Y, and Z. So some may offer only one of these as an option and I see nothing wrong with this. Just as some luthiers will not build with a customers wood. You have to build something that you as a luthier approve. You can't just grow a dovetail or a bolt on because the customer wants it. If they wanted a soundboard made of ebony would you do it?

The fact that there are so many different ways to build a guitar is part of what makes them so unique and diverse. It's part of the beauty of the instrument.

Hi Zeke

I get what you are saying, but maybe I can add something else, so that I am a little clearer. I would have to disagree with your 'you can't just offer what the customer wants' - within what are considered established principles, this is surely the whole point of providing a bespoke service- the customer selects the builder they want based on a number of factors and works with them to get the instrument of their dreams. I am not talking 'ebony tops' but where equally appropriate alternatives are available, the builder has a choice, be able to offer both equally as well, or run the risk of the customer going else where.

I am sure that there are some that would not want to be flexible as they have their method and that's all they offer, and that is their choice and fair enough. We can't after all forget that this is a highly competitive space and some will use their design features as a differentiator, which is again fair enough... But I remain unconvinced that one is better than the other, as Both options when properly executed have pros and con, but offer a decent solution to the engineering problem. Therefore, IMHO, being ina position to execute all types well is in itself a competitive differentiator. Customers having more choice is a good thing.

Have to say I don't agree with the attitude of never building with customers own wood... All depends on the quality of the wood and then ensuring the customer appreciates that the builder will want to store it for a for while to ensure its stable... But if its decent high end stuff, can't see a problem. Refuse to build with inferior stuff naturally, but dismissing it out of hand seems another element of inflexibility.

When you build 10 a year selling at $15000 + I am sure you can turn folk away if they don't agree with your approach, but for most, as long as you are not compromising your build quality, flexibility is surely a good thing, and that comes with learning to execute as many methods to the highest standards.

Very true frank. I just do the guitar building thing as a hobby so I'm personally not worried about losing work. I'll do guitars to my standards and if I don't want to do what a customer wants I dont have to haha

I deal with enough making stuff I don't agree with in my day job that I don't want to bring it into my hobby as well but I completely get that those who are making a living need to offer both. In my machine shop I cannot tell you the number of times I've done what a customer asked, even after being warned, and then have to remake all the parts differently when they fail (at the customers expense of course). I've also made things a way a customer asked that caused them to pay 2-3x as much as it should because they think their way is better. So I get how compromise is part of the business aspect. To me though building guitars is a hobby so it gets done my way hahahaha

I guess though what I am saying is that the consensus seems to be that if executed properly, it's not a compromise - well not in any negative way. I am totally with you on refusing to compromise on anything that you consider to mean an inferior result or below the high standards you set yourself. - that goes without saying... But where the professional consensus is that there is no difference in terms of quality, being able to offer more choice is surely and advantage?... A round about way of saying it must be good to learn both?

I am the same as you, unlikely ever to this professionally so can stick to what I know and like, but I would say that I can learn more and improve my understanding by learning how to do both well.

True it would be good to learn both. I personally will probably never make a guitar with a dovetail because I believe the downsides outweigh the upside. I may experiment with the joint but never use it on an actual guitar because I don't like the difficulties it will cause in a neck reset situation. If I was doing a neck reset I wouldn't want it to be a dovetail so I'm not going to put anyone else in that situation that I would hate to be in.

Know what I mean, Vern? Haha