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I'm ready to put my bolt on neck (MJ) & want to glue the FB exstention. Will TB stick to EM6000 or any other glue for that matter. Or do I have to get rid of all the lacquer?

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Mike McNerney

We clean off the finish to within 1/8" of the edge of the extension, but only glue a narrow band ... approximately the 1/8" of lacquer remaining plus 1/4" of wood. That is enough to keep the extension on and makes removal a bit easier when and if.

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A constellation only takes shape when one maps the whole.
- Beth Brower

Maybe I'm just getting impatient but after some razorblade scraping I'm still getting lacquer & am wondering about the same principles of the bridge gluing,
so I thought why not use an adhesive like titebond melamine glue.

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Mike McNerney

I very carefully apply stripper with a Q-tip, then scrape the remaining or get under it with a chisel after scoring the perimeter of the area I'm removing with a scapula. The scoring is very important. It keeps the finish from lifting beyond the point you want it to.

Too late at this point, but is there a reason why you don't just tape that area before finishing like for the bridge?
Mike

I wouldn't worry about removing the finish, and I would only glue the end near the soundhole. That joint is usually in compression, and adhesion is irrelevant. If the joint is in shear, it's better for the glue to fail than the top to crack on each side of the fingerboard.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I mask off to about 1/8th" in the extension area. Prior to gluing knock off just the ridge left by the tape and glue down with 4-6 dots of Elmer's School glue. It's enough to hold it down and I can remove one in about 10 minutes if need be.

Yes I should of masked it in the beginning. Next time! thanks all

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Mike McNerney

You definitely want to scrape to bare wood for the bridge. The FB extension maybe not so much but I would still do it. IMHO that is part of the neck joint. I tape like others have suggested but I have done it without taping off too and certainly have scraped tons of finish off of cheap guitar bridge repair jobs and I've found the best tool to be a chisel freshly sharpened leaving the burr in place on the back edge, IOW don't hone the flat back of the chisel at the very end of sharpening.

I'm with the no glue crowd -- never had a problem, it certainly works on jazz guitars and the instruments in the violin family since the extension does not even touch the sound board. It would seem if need be scraping out a section large enough for a few drops of glue would suffice. Allegedly there is a popular instructor on the east coast that not only does not use glue on the extension but also uses a single bolt to attach the neck.

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Ken Cierp

http://www.kennethmichaelguitars.com/

http://luthiersforum.com/forum/viewtopic.php?f=10101&t=49233&hilit=fingerboard+extension

If low action and having fretwork last after dressing are important to you, glue it. Humidity changes are inevitable in every guitars life.

As mentioned, we usually tape the extension patch with standard 3M blue tape to minimize the work of getting a clean edge to glue to, but it's easy to rout off or score/pop off or use a warmed pallet knife (lacquer) to clear the patch. A lightly beveled scraping to remove any raised edges (just as on a bridge patch) is the usual practice here to finish the prep for gluing. We glue with hide because it is easily reversible without extraordinary cleanup measures, and that two inches of gluing area (4" x 1/4" x 2) will carry a few thousand pounds of shear loading along the fretboard axis.

There are some key differences between floating fretboard extensions and glued or bolted extensions - a properly done floating extension has a great deal of resistance to changes in geometry because it is largely decoupled from the top, while traditional flattop extensions are relatively weak in bending (the difference in having 1/2" or more of neck wood and fretboard resisting bending loads versus 1/8" of ebony). Gluing or bolting a standard flattop extension to the top utilizes the stiffest area of the guitar body (the neck block/UTB/#1 back brace structural box) to maintain proper geometry and prevent the extension from being driven into resonance. Extending the neck block well beyond the edge of the fretboard and a well tapered upper transverse graft are our preferred methods to address cross-grain top failure in tension (versus shear) due to misbehaving fretboard stock.

We've seen unglued/unbolted extensions buzz like woodwind reeds, and what were apparently tight fits out of the builder's shop on an extension end up with several thousandths gap after a few months and an hour of our time to quiet them down. As is frequently mentioned here, repair experience informs construction, and chasing what was ultimately a fretboard extension buzz was a great way for the boss to make the point with me that some things that seem like good ideas to builders can be challenges for repair people.

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A constellation only takes shape when one maps the whole.
- Beth Brower

Yup, the shear strength of the tongue is an important aspect of keeping the neck at the right angle. Just a thin bead around the edge of the tongue.

I have started to bolt down the fingerboard extension.
It seems to me that you undo some of the advantages of a bolt-on neck design when you glue part of the system. But it is necessary to fix the fb extension down to the soundboard to avoid that buzzing problem that others have mentioned. The Gore/Gilet books present a method for a bolt-on/bolt-down neck attachment. Most recently I have used this method from Luthier's cool tools (I have no commercial interest - just a satisfied customer) - it works really well and achieves the same objective as the Gore/Gilet method.
http://www.luthierscooltools.com/Tools.htm#Bolt-on
This way you can remove the guitar neck in moments with a hex key, or even use finger bolts on the extension.

I apply masking tape around fretboard extension. Then after removal, I apply more moving in about 1/8". Scrape and sand to wood. This is not about mechanical strenth. Just a good clean fit, no vibration. No glue in the joint!