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On my builds to date I have used mainly M&T bolt-on neck joint and glued down the fretboard extension, but often wondered if it is necessary. Obviously if it wasn't glued, removal is easy if ever it was needed.
This led me to thinking maybe double sided tape may be an alternative. Has anyone ever used double sided tape for this?
Your thoughts would be appreciated, thanks. Mike.

Glue it it needs to be coupled to the box. Double sided tape would be a nightmare to get to release and it's not what anyone would expect to find in there. You may not be the one removing the neck someday making predictability in servicing highly valued. Additionally double sided tape may come loose, may prevent the extension from being completely down on the top as well.

Mario P. once shared on this forum that he uses a small puddle the size of a quarter (US currency) of Elmer's carpenter's glue for the extension. Makes releasing it with a little heat very easy and clean. So I had built 15 when I read this and built the next 40 his way with the small puddle for the extension. None of mine have ever required a neck reset to my knowledge yet but it's obvious from someone who does remove necks from all manner of manufacturers that the small puddle is a great idea.

Good luck

Thanks for your input. It would be very easy to remove with a little warming up, far less than heating for glue. You do have a point about somebody else in the future having to remove the neck. The small puddle of glue seems a good idea but I'm not convinced that it would couple it to the neck any more than tape though. If the tape failed it would be easy to remove the neck and replace.
This is just an idea that came to mind and I'm not necessarily set on doing it, hence the post to find out whether it had been tried before. Cheers Mike.

Mike the small puddle of glue under the fretboard extension is currently being done by many builders and has been done for years with no issues. You may not be convinced that it couples the extension to the top but I am. It works fine. Hundreds if not thousands of guitars have been built with Mario's method now, he shared it around 15 years ago.

I have never heard any reports that it did not couple the extension completely nor I have heard any reports that a buzz or vibration resulted or that it came loose.

Getting the extension to release easily is not difficult to do with Mario's method. I don't understand what problem it is that you are trying to solve.

You replied that if the tape fails it would be easy to remove the neck and replace presumably the tape. Why would you ever replace tape if it failed?

Also why do you want the removal of a neck to be all that easy? Removing a neck is something that should only be required on a conventionally built acoustic guitar at reset time if that even ever comes.

There are millions of guitar players who argued for decades regarding the dovetail joint vs. a bolt-on neck. Both camps want the neck and body as securely coupled as possible citing tonal advantages... How do you think they would feel about a neck partially attached to a body with double sided tape?

Lastly in the bolt-on neck world most implementations use steel bolts to couple the fretboard extension to the body, no tape for these folks either.

I use double-sided tape on the fb extension to hold it down while I level the fretboard before I remove the neck and install frets. The double-sided tape isn’t secure and is quite easy to remove. I use Titebond under the extension for final assembly. It’s not hard to heat and remove. I tried Elmer’s white glue—it wasn’t reliable.

Long ago, I experimented with not holding down the extension at all. All of the frets above 14 were quite dead sounding.

And how, exactly, could 'failure' of double-sided tape be detected?

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Peter Havriluk

Indeed. You really need the coupling between the extension and the top to get good tone above the 14th fret.

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Well it seems like there are contradictions going on here. From what I read above the only place to get good tone above the body join is if you fret exactly where the cent size puddle of glue is located. There also builders who endorse no glue at all so who's right and who's wrong?
I'd like to point back to my original post where I do say that on all my builds I have glued the extension down, so I do see the merits of it. All I am trying to do here is question whether it is really necessary and if an alternative way is an option.

I wouldn't try to reinvent the wheel on this one, 99 out of a hundred glue the fretboard extension down. Glue the entire surface.

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I think this is a legit question and deserves some serious responses.

There is more than one way to look at it. While I probably wouldn't use double stick tape, I have inserted a piece of plain copy paper between the fingerboard extension and the top (HHG). I've run into other builders who do that too. Ease of removal being the objective.

I also build with the fingerboard extension "completely uncoupled" from the top, cantilevered violin style. When building that way the FB extension is always supported with additional wood to keep the FB stiff enough to play.

So are dead sounding notes because of the FB not being stiff enough? Or is it because it isn't "coupled" to the top? I think the former. most guitars are so heavily braced above the soundhole the upper bout is already "decoupled" from sound production. Granted, gluing down the FB does make the neck/body structure more rigid and there by probably helps transfer energy developed in the neck to the body. But I think that is something different than what I would call tone coupling.

There are respected builders who cantilever fingerboard extensions and make great sounding guitars. The idea being to include the upper bout in sound production. It makes sense to me too, and why most of mine are built that way. Sure, this is different in the opposite direction from the OP but it is part of the equation. The whole violin family, mando, and a lot of guitars have FB extensions totally uncoupled and they are still great sounding instruments.

I'll add that a typical FB extension is not stiff enough (because of fret slots/thickness) to support play over the body, the question to me is -- is it coupling with the top what makes the sound better or is it just that gluing it down is providing stiffness to the structure and FB extension? I think there are at least 2 different things going on here.

Sometimes you just have to muddy the water.

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Brian R, Wood Mechanic
N8ZED

Yes, fingerboard stiffness is the problem. Cantilever fingerboards need some structure to stiffen the floating extension, which requires raising it farther above the top, which requires tilting the neck forward to keep the strings aimed at the bridge, which then makes the guitar want to fall away from you when sitting on your leg. I don't like it.

Gluing the extension to the upper bout allows it to make use of the soundbox's existing stiffness. Double stick tape would probably do the trick as far as tone goes, but glue also makes use of the extension as a brace for the upper bout, and to keep the heel cheeks from indenting into the ribs with softer side/binding wood.

As far as sound production from the upper bout goes, I'm of the opinion that it's negligible if you have the soundhole in the usual place and no unusual bracing like flying buttresses to take the headblock load off the soundboard. Difficult for any vibration to make its way around the soundhole in the first place, and even if it does, the upper bout can't be flexible enough to make much use of it.

McPherson's solution is an interesting one, positioning the soundhole so the unavoidable perimeter stiffness can serve as half of its support structure. The upper bout still needs to be fairly stiff, but at least there's a wider path around the hole to carry vibrations.

It's also possible to put the soundhole in the side of the guitar so the soundboard is entirely unperforated.

Or for the very most freedom, you can use the force-free bridge technique, with a tailpiece and counterbalancing horizontal break angles in the saddle. Theoretically it would be possible to have the bridge float in free space without a soundboard at all But of course you'd need some other structure to support the force between the neck/headblock and tailpiece/tailblock. And as far as I know we still have 6 more years to wait until the patent runs out. I never was able to find the patent, but 20 years from the date on that post it should certainly be expired.

Mike there are no contradictions happening here you are just not accepting sage and time tested advice and you want to push back. I don't know a single builder who endorses no glue at all and if they do they are wrong, period. There is always going to be someone with a bad idea and that does not make it a good idea.

and conversely!

Fair enough.

Brian cantilevered fretboards are very much an accepted way to build and different as well I'm sure you know. Some of my detail here is for others who may not know. It is perhaps one of the oldest ways to build with Antonio Stradivarius to Ken Parker employing same. Ken's going to be pissed at me for implying he's 400 years old... It's a different animal from an unsupported, kerfed, stress induced by force fit freted fretboard extension structure with a nasty tendency to curl downward initially and upward in time attached to a vibrating guitar top.

Sounds like a harsh environment doesn't it especially when the vibration transmitted by the frets and fretboard are supposed to be transmitted to the underlying structure, the box.

There is the issue of when a guitar starts to fold into itself, neck reset time. Double sided tape will permit the joint to slip but without any warning that it's slipping in time. In fact I would not be surprised if neck reset time comes sooner all other things being equal with a taped extension on a conventionally built acoustic guitar. The coupling to the UTB is now accomplished by soft, double sided tape and not a hard, immovable glue joint.

Many builders, myself included see the UTB as key in keeping the guitar's geometry static as long as possible and an opportunity for stiffness in the upper bout with the extension coupled to same. Some of us even augment the UTB with CF for this very reason.

For what this poster described a conventional fret board extension in direct contact with a vibrating guitar top double sided tape is a very bad idea and people here learning to build guitars should not see it as anything else. One poster described using it for temporary reasons which is clever but he also reports it does not hold.

EDIT: Wanted to add that the reason why double sided tape won't hold and is a bad idea has been mentioned, twice in fact.

Conventionally built acoustic guitars are always under string tension and this tension encourages the entire structure to fold into itself. Neck reset time...

There are examples of double sided tape used on guitar tops and here are a few:

1). Pick guards may be attached with quality, 3M double sided tape even with great care to select tape with the least thickness of any material possible.

2). On the arch top guitars that Brian brought up double sided tape can be used, although I don't like it... to "pin the bridge" once proper intonation is dialed in. We use double sided tape because it comes loose.... and we can remove, replace and relocate the bridge when the player changes string gauges and that calls for resetting the intonation. Double sided tape is specifically employed here because it does not hold well over time and can be removed.

In both examples above the joint between the surfaces is not in shear. The fret board extension is subjected to shear stress and that is the primary reason why double sided tape is a bad idea in this joint. There are other reasons, mentioned too but this is a joint that wants, constantly to move and when it does what results is distortion of the upper bout including the sides that is permanent and requires the neck angle to be reset to correct.

Or, in other words that little puddle of Elmer's Carpenter glue is part of a series of glue joints that keeps the neck angle static over time countering string tension.

Some of the other reasons are we see guitar all the time for a ski ramp at the end of the extension. The board initially curls downward under compression from frets in slots and then it can curl upward creating a ski ramp. Although a Fender style bolt-on neck is not what we are speaking of the single most common reason whey folks with Strats and Teles and such can't have low action at times is the fretboard has curled with a ski ramp that needs to be milled out with a fret dress.

What does a Fender neck have to do with this discussion? If a fretboard on a Fender style neck can move into a curl and STILL be glued well to the hard maple under it what do you think this curl will do if it only has double sided tape to stop it....

Or, in other words fret boards curl and it's very common. A good bond with the top, UTB, block is key and very much part of the overall idea that Ervin (Sompgyi) promotes that a guitar, the entire guitar is a monocot.

I have this question running on another forum, with similar reluctance from some to accept anything new. One member, however, did state he might try something similar but use the masking tape/ ca glue method instead. To be honest, that seems like a better idea, as there is no residue to remove and the joint will not be soft as Hesh fears but will give a more solid adhesion. In effect, it is a glue joint but sandwiched in between tape.

You have it wrong Mike there is no reluctance to accept something new here. There is a reluctance to promote or further a bad idea on a forum where someone may take this idea and run with it and then have a failed instrument that results. There is a difference between pushing back on a bad idea and being closed to something new.....

My hope is that you don't continue to be personal because you cannot accept the very advice that you asked others to provide. I can get personal too but prefer to try to stay on mission and lend a hand, share experiences, etc.

So CA is not serviceable and would be a nightmare under the fretboard extension requiring so much force and heat to release other glue joints in the block region may slip in the process. We also go in that joint with pallet knives and if you extend the time and effort required to release this joint you increase the possibility of damage to the instrument caused by the Luthier AND the incorrect glue choice originally.

CA should never be used on anything that has to be serviced (released) in the future with the exception of frets where heat is easy and safe. CA would also be very counter to the idea of an easily removed neck.

So look Mike you accuse me of being closed to something new, this is not new it's simply a bad idea and you won't let go and move on. I've asked you what problem it is that you wish to solve using tape in a joint that tens of millions of guitars have glued?

I still would like to know what you have in mind, why do you need to remove the neck more easily than the five minutes it takes me including set-up with heat lamp to release a joint with a small puddle of reversible glue?

Maybe I am missing something here I do it all of the time so I am genuinely interested in why you want a removable neck seemingly with less effort than the alternative?

Thanks, I'm of to work I have 5 guitars waiting for me to repair this morning and I'm happy about that. Be back later.

I use a lot of blue tape and CA for CNC work. Just remember it’s only strong in one direction. That’s why we use it to temporarily affix the work to the spoilboard and why it removes cleanly.

FWIW, I’m in the puddle of Titebond camp because I’ve taken enough of my own necks back off to know it’s not difficult to remove, cleanup and prepare to re-glue.

I have a strong desire to go to the bolt on / off joint but I have too many plates spinning as it is.


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Hesh, so you've decided it's a bad idea, I can't help you. Please bear in mind I'm an amateur builder with around 30 builds under my belt. I'm not in it to make money, it's purely a hobby and I am still learning and don't have enough time left to learn everything. All I have done is ask this question to the forum quite innocently because I like to learn. If I won't leg go, as you put it, it's because the responses to my post have not been convincing.
During my time on the forum, I have posted a few times with various questions and found everybody to be very helpful, including yourself, for which I am grateful. However, on this occasion it seems we differ, so be it.
So now I will move on, and as I've not had a satisfactory answer to my question, I shall probably go and glue down the extension on my recent build.
Thank you for sharing your thoughts. Mike

If you ever want to compare notes on the bolt on/off joint, just let me know, Brad. I think it is well worth the extra work. Plus, it really isn’t that hard a plate to spin. Of course, this is coming from someone whose many plates are dangerously close to hitting the floor at the moment . . .

FWIW, I also rely on the shear strength of glue to prevent the tongue sliding forward and changing the geometry. Instead of a puddle though, I run a very thin bead (1/32”) around the very edges all way round. That way if you do decide to pull the neck, you never need to get a knife more the 1/4 or 3/8 under the tongue.

That said, I have found with the bolt on butt joint, you don’t need to remove the tongue for a reset. Just clamp the extension down as if you were gluing it making sure to leave a hinge point at the body joint, pull the bolts, press the neck forward to open the joint to get some flossing paper and get to work. Takes about 15 minutes, no heat required.

I recently had #5 of my budget line in from probably almost 20 years ago by now for a reset. Turns out it had an M&T with the barrel bolts and a glued tongue, and the same technique worked.

IMO you’re trying to solve a problem in a manner that may present problems not foreseen yet. It would be easy enough to test on scrap. Double stick tape some ebony or whatever you’re using for fb material on finished and unfinished spruce, leave it for a month or two then see what you have to go through to remove it. I suspect it won’t just peel right off like you think. The double stick tape I becomes very very stubborn after time.

You are welcome Mike and I appreciate the detail here. I would like to be helpful and I appreciate your curiosity and situation. Please feel free to contact me directly if you would like to discuss this or anything further I am one PM away and I help a lot of people here who do not post on the forum and it's done by PMs.

I did ask two other life long luthiers about the use of double sided tape under the fret board extension this morning while I was at work in our lutherie shop in Ann Arbor, MI. Both said the same thing I did, it won't hold, the joint won't hold up in shear, it will weaken the monocot structure of the box and result in early neck reset being required and it may be a tone and vibration suck.

If you are not convinced give it a try and see what results and report back.

You did say that you remain unconvinced and there is only so far any of the rest of us can do to convince anyone of anything. I still would like to know what problem you are attempting to solve and why you want an easily removable neck if you would please answer me? PM is fine. I was asked this same question, what the problem is by both pro luthiers I consulted this morning so there are several of us who would like to know.

Thanks Mike

In our discussion this morning all three of us thought the same thing a bolt-on with the extension also bolted-on would be a structurally sound manner to attach the neck with minimal vibrational loss from incomplete coupling of the two subassemblies, the neck and the body. Ask Taylor they made a name for themselves largely from this very idea of a bolt-on, easily removable and changeable neck angle neck.

" I still would like to know what problem you are attempting to solve and why you want an easily removable neck if you would please answer me? PM is fine. I was asked this same question, what the problem is by both pro luthiers I consulted this morning so there are several of us who would like to know."

Hesh, you keep asking me which problem, but really it's no big deal. Maybe the answer lies partly in your question i.e. that pro luthiers would like to know. Once again I remind you that I'm an amateur. Try and remember when you were one, and certain procedures seemed daunting. As pro luthiers, you will have the tools and experience to make the reversal of a glue joint second nature, not so as an amateur. I had to remove a bridge a few years ago, and also a fretboard. I didn't find either task a pleasurable experience. I don't have all the fancy heating equipment and jigs you have in a pro shop.

So, with this in mind, I try to make my life a bit easier, which in this case led me to thinking there may be an easier way to undo a neck if it was attached differently. It's a problem that is unlikely to be one I'll ever have to deal with, but it doesn't stop me thinking about it.
Cheers Mike.

Glue, puddle or completely. I've taken 2 of mine (completely glued down) with heat and patience reasonably easily and without any drama.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Your original post asked for our thoughts. You have received a lot of thoughts. My thoughts are glue it down, and don't use tape.
As Nike says: " Just glue it."