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I recently bungled a neck attachment ( improper set, i.e. too high ) and now have to remove it to do it properly. The fretboard extension is attached with fish glue, the neck is bolt on. Could anyone suggest the proper procedure for removing the fretboard extension, or is it necessary at all? Thanks.

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Under Compensated Nut!

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I'd be careful adding any water. Every time I've tried that everything turned black with the heat/water combination. I don't know the answer, but fish has a very high temp resistance. Someone with experience probably will chime it.

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Waddy

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not of much help either, but i can second Waddy´s comment - i unglued a fretboard with heat and moisture and even if i got zero wood failure, i got a mess of black goo on the soundboard, which eventually leaked into the wood and stained it permanently. live and learn, they say.

good luck,
Miguel.

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member of the guild of professional dilettantes

Ill Third It...

Never use water on a guitar (PERIOD).

The only time I have water around a guitar is when steaming off a neck and then I make sure it isn't spitting out water. Even at that if you have ever removed a neck that has been steamed off prior to you doing you will see that the joint is usually discolored and black-ish.

Heat is the only way I would recommend removing anything on a guitar.


Cheers,
Bob

Let me apologize for 'hightailing it' and deleting my earlier post in which I advised the original poster the advise of using heat and water.

...For what it is worth, I didn't offer that advise without having tried it, and knew that it worked on my own builds, bolt on neck/ extension glued with fish glue...
Maybe the heat combined with the water loosened it...
maybe the heat didn't help at all...
Maybe it was just the water.
After reading the spec sheet for my fish glue it does clearly say that it's heat resistant, so I'd tend to agree with Waddy on that point.... maybe my use of heat had no effect.
Fish glue however, does release with water, and to remove the extension, it seems (one) would have to use either heat.... water...., both(heat and water) or just saw it off( attempted humor)

I have removed dovetail necks using steam inserted in a hollow needle (usually) under the 15th fret, and I can't remember not having that process create water... perhaps my technique is flawed..

I am the only one, so far in this conversation, to have offered advise based on actual experience..
I'm certainly interested in learning a better way of doing any process, this one included.
thanks
jack

I admit I have Zero experience with Fish glue but I do know it is similar to hot hide glue in that it is an animal glue made from the collagen dirived from the bones and connective tissue. I am only assuming it will loosen up using heat much like HHG but again I have never used it. I only use HHG and Original Titebond for gluing anything I want to be able to reverse. So someone with experience with Fish Glue probably knows better.

Having said that I still believe you should never use water on a guitar except in the form of steam.



How I do it is pretty simple. I have a wast basket directly under my espresso machine which I put the end of the hose and needle in. When the espresso machine is hot and ready I switch the knob to produce steam. Obviously steam makes water when it condenses so at first the hose is cool and it will produce water drops spitting out of the hose. When it is pushing just steam out I grab the end and give it a few quick raps to shake any excess water out of the hose. When it is pushing just steam out I insert it into the joint and only give it about 10 seconds or until I see steam coming out of the second hole. (I always drill 2 holes one for steam in and one for steam out). I let it sit for about 2 or 3 minutes and repeat the process raping the water out of the hose. I do not inject steam for more than just a few seconds at a time because you run the risk of it condensing into water. The object is to heat the joint up with the steam and introduce as little moisture as possible. After about 10 or 15 minutes of this the joint should start to loosen up.

I have seen people wreck guitars by injecting steam into a neck and just leave the needle there until water starts coming out of the joint or worse it starts running inside the guitar. The danger in that is that you can literally un-glue the headblock from the guitar. Quite a while ago I had someone bring me his Gibson J-45 that he had someone do that to his guitar. They had no clue how to remove a neck properly. When I got it, the top was discolored and warped, the headblock was separated away from the sides and the top and the finish was all blushed from the steam (turned white).

So water is a bad thing for a guitar and steam is almost as bad if someone doesn't know what they are doing.

Cheers,
Bob

Since no one answered your original question, try it first with the fretboard extension attached. There's no point in taking it apart if the neck is bolt on, unless the reset is extreme. Just unbolt the bolts and floss the cheeks with sandpaper. So the answer is don't take off the extension unless you have to.

I've never used fishglue, but IMO people are irrationally paranoid about water. IME, use it in small amounts if necessary.

There's no way steam is going to work for loosening the fingerboard extension without destroying the finish around it. The conventional thing would be to use heat on the extension, and work it loose with a thin palette knife.

Fish glue does indeed have a high heat resistance so using heat is pointless. Water is your only answer, which isn't a very good answer. I would get some UNwaxed dental floss, get it wet, and slowly work it back and forth under the extension. This will take awhile and you have to likely re wet the floss and probably get new pieces frequently but you won't get any water damage on the guitar this way. And there won't be any residual problems like when using steam.

@Greg B, I hope you (or anyone else) didn't think I was suggesting to use steam to remove a FB extension. I was answering Jack's question about how to NOT get water in a neck joint when removing a glued on neck.


If Fish Glue does not let go with heat then that is another good reason to never use it on anything that would need to be repaired.
It would be a shame that all these guys using it for guitars are just building throw away instruments. I will stick to HHG and Original Titebond than you...

Bob

I disagree with the notion that fish glue will not release with heat.
I use it for pretty well everything, and had the "opportunity" a while back to remove a fretboard.
All I did was lay my silicone heat blanket on a piece of MDF, set it for 300, set the neck on top, (with thick cardboard protecting the top) wait 12.7 minutes till it it got real warm, then floss and palette knife and it released just fine, no marks, damage, seeping, nothing.
I have also heated binding with a heat gun where there was a bit of a gap - the fish glue released, I re-clamped, all good.

I have a vague recollection of trying to remove a fish glue joint with heat. I say vague because it was 4 or 5 years ago. I know that I was left with the impression that it was actually a touch harder to remove than HHG.
We know that HHG does not act like PVA or Titebond in the way that those particular glues release. In my experience HHG can take much more heat than Titebond. That is why you often hear the idea that HHG needs both heat and moisture for the glue to release. For the most part they are correct. It may be the case that a lot of heat will make HHG brittle, allowing the palette knife to wedge and 'crack' the joint open. That is also the theory of running alcohol into joints - alcohol also supposedly makes HHG brittle.
I suspect that Fish glue will act in a similar manner to HHG. Certainly you should read the runout of the soundboard and insert the palette knife accordingly. Of course on a bookmatch that is going to change, dependent on which half you are working.
I keep repeating it but the best way to tackle such things is to glue up a few trials with the type of glue that you used. Try to replicate the types of wood used - so the 'standard' would be a thinnish plate of Ebony on to some Spruce. Allow these few test pieces to dry for a few days and then . . . practice. This will allow you to see what effect heat alone has on your particular glue. It may also tell you if you are reading the runout correctly and whether your palette knife is too sharp or too blunt.
Violin repairers often lubricate the palette knife with dry soap. It supposedly helps the initial entry of the knife into the joint. Some may then switch to a knife that has more of a blunt edge so that it acts more towards a wedging action. This is where you really do have to be aware of grain runout. Get this wrong and you will make things much, much worse.

I think it depends on how well cured the glue is. In the case of your binding at least I'd bet that you heated it relatively soon after initially gluing-not saying the glue wasn't set but that there was probably still a touch of moisture in the glue or surrounding wood.
I've definitely reheated and closed a gap or two the couple of times that I've used FG for bindings...I've also tried to separate a well-cured FG joint with just heat, pretty tough.
Things like FB extensions I like to lightly glue with Titebond because it's a breeze to separate a TB joint with a little heat.

So it sounds like there is a lot of conflicting info about Fish Glue...

For me, that is a good enough reason to never use it.

My suggestion to the original poster:

Pull the joint apart the best way you can, Clean all that crap off and use Hot Hide Glue. You will be assured 50 or 100 years from now when some future luthier is repairing your guitar he will be able to do the job correctly and not have to ask himself why the hell back in the 20-teens did idiots use fish glue on a guitar...

HHG has been used since men were walking around in caves with clubs. It has been "time tested" on instruments to hold very well and is reversible years and years after it was put together. The best part about it is you can heat a joint up, repair the part and you don't have to remove the old glue, just heat it up to 145 degrees and stick the parts back together and it will hold like it was new.

That is my 2c for what it's worth.

Cheers,
Bob

It's not so much that there is conflicting information about Fish glue, just not enough testing. You get conflicting information about any glue. I've been around instruments long enough to have heard all the rubbish said about HHG. Oddly enough there was a time in the late '70's and '80's when Guitar makers thought it was very weak. Too weak for any of the joints that were placed under any stress. It became such a mantra that virtually the only people that were using it were the Violin and Lute makers.
It just needs more testing to be done on Fish glue. I honestly think it behaves very similar to HHG when subjected to heat (heat alone). If it's releasing easily when subject to heat I agree with William, in that the joint hasn't cured for long enough and it's the residual moisture that is assisting. I'll soon find out because I have a test piece glued but my memory of trying to release the Fish glue joint 4 or 5 years ago suggests that it's little different to HHG.
The other option to consider is whether a full strength HHG/Fish glue bond is necessary under the fretboard extension. I deliberately weaken the glue joint under this area but (a) I don't make SS Guitars and (b) I did enough testing of my procedure to put my mind at ease.
I glue the fretboard with HHG btw. That doesn't imply that I think Fish glue is unsuitable for the task though.

Michael, You very may be correct in there has not been enough testing on using Fish Glue on guitars. I know it was used in the art world as a binder for some 2,000 years but not sure about its use for guitar building. I personally see it much like using epoxy as a filler. It also is being tested by many luthiers but has not been time tested. By that I mean there are no guitars around that are 50 or 100 years old that have been filled with epoxy. For that sake only I will not use it and much prefer the standard finishes that I know will be around for years and years to come. I am just getting into building but I do want my guitars to be around many years after I pass on and more than that I don't want some future luthier to look at something I have made and scratch his head and ask why the hell would they _______ (fill in the blank).

I just visited your site Michael and love your guitars... I would love to pick your brain a bit if you wouldn't mind. I have a real love for the Romantic Era of guitars.

Cheers,
Bob

I tried heating through a test piece with Fish glue. A full 2 days (48 hours) after gluing and it released quite easily with heat. I'll try the same test but give it a full week.

I tried heating fish, it does release but it was only after a day or so. I notice HHG harder to remove with heat after it sat more than a week however, to the point that a little moisture was necessary.

I never thought you were only supposed to inject steam for a few seconds, always assumed that steam goes in until neck joint comes loose. But I guess for some guitars like Guilds where they put so much glue in the joint, that it might take a while to steam it off. When I do it with my guitar I can do it without damage simply because I use very little glue.

The other problem is on some guitars, the neck block is very thin, meaning if you drilled a hole in the 15th fret you will actually poke the needle into the body rather than the dovetail. Not sure what the right solution should be...

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Wait... fish glue? Just wave a damp paper towel in the air and catch the fingerboard as it falls to the floor. If that doesn't work, put on some gloves and loosen the extension with your brain.

Thank you, thank you, I'll be here all week.

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George :-)

Or just use a worm on a hook...




I have never found that HHG wouldn't loosen up if heated to 145 degrees. I have repaired some 40 to 50 year old Gibson's and Martin's and have never used water to remove parts.



Some people do but I don't. I have found from experience that a little goes a long way. As long as you keep the joint hot the glue will release. I assume you are using a neck removal jig to apply pressure on the joint? If you do then you will see the joint coming loose as you apply the steam.



Don't drill your holes angling back to the heel block. I drill 2 holes slightly angling them toward the heel and in a slight V pattern toward the center of the heel. That way you will pretty much drill only into the heel and not the headblock. The slight V pattern keeps you from drilling through the side of the neck (a very bad thing to do). When I inject steam into the joint I watch very carefully for steam to come out of the other hole. As soon as I see it come out of the other hole I pull the needle and wait a couple of minutes and then re-insert and repeat. It doesn't take too long since steam is much hotter than 212 degrees (boiling point of water) and HHG melts at 145 degrees.

Hope that helps.

Cheers,
Bob

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

I was going to ask when you heat up that fish glue does it smell like fish?

nope

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Steve Smith
"Music is what feelings sound like"

Questioin is: did the OP get the extension removed? Wilb?

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Steve Smith
"Music is what feelings sound like"

Steve, nope, haven't attempted it yet. This is a new guitar and and the action at the 12th is 0.125. With the anticipated bellying I've usually experienced on previous builds, I expect that to increase. However, the humidity has been extremely high where I live. And the guitar has been sitting in that humidity for awhile. So, I have placed it in my humidity controlled assembly room and waiting to see what happens. But i still expect that I will have to reset the neck.
In any event, thanks to the generous input from forum contributors. Your discussions and thoughts have provided me with information that I will need.

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Under Compensated Nut!