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Hi Guys!

What is the difference between butt-joint bolt on, mortise and tenon, and just bolt on that I see on Collings guitars?

What exact method do Taylor and Collings use?

thanks, David

A butt joint has no tenon on the neck and butts flush to the rim and a M&T does have a tenon on the neck that fit into a mortise in the neck block.

Tayor uses a hybirdized M&T where the heel is actually a shallow tenon. See their web site under Guitars/ Features/ TN neck. Off the top of my head I don't recall what Colling's neck joint is

Collings uses a dove tail shaped mortice and tenon joint with bolts in the tenon and the nuts on the block end as apposed to the more typical threaded insert nuts in a straight tenon and placed in from the block side.

Collings


typical mortise and tenon bolt on neck


butt joint bolt on


Taylor Hybrid bolt on joint

Michael, who's is the third example, the butt joint bolt on? It looks to me not, in fact, to be a butt joint, but a 'floating' neck-body joint with 3-dimensional adjustment. It's not a Doolin, I don't think it's a Swanson (it's not set in), I wouldn't even think it's our friend Mr Turner's. I'm intrigued.

edited out for stupidity

It is a Yamamoto guitar the neck joint is based on Harry Fleishman's design and you are correct it has both yaw and pitch mechanical adjustment but I thought it a good example of how a butt joint looked

Also of intrest it appears that the extension is held aginst the rosette area with a recessed piece of double sided tape

Thanks Michael. Double sided tape??!! Can't see the point really. Most neck-body junctions of this type leave the fingerboard extension floating. Hence the CF rods or tubes epoxied into the fingerboard to give strength.

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I know but if you examine the end of the extension real well there is either a piece of double sided tape or it could be a thin piece of UHMW or something recessed. He does not really mention what this is. I took a wild guess

I'm betting on compressible foam rubber of some sort, to stop the possibility of the extension smacking the top under pressure or rattling/buzzing.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Maybe white felt. You can get felt padding in different thicknesses and hardness.
Cool setup though.

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Horton, MI

I wonder if you built 2 "identical" guitars, except use the Taylor joint on one and that Yamamoto style on the other, if there would be any difference in sound.

The Taylor has that entire area of contact and the Yamamoto has 3 tiny points, well I guess 5 if you count the screws. The Taylor just looks way more solid.

Any thoughts on that?

Sorry for the hijack.

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Horton, MI

I'm just thinking out loud here but I would think that any compressible material would be dampening to the upper bout and not where we want to go. To me the fret board extension should either acoustically couple with the guitar or be physically isolated completely from the guitar top as in elevated fret boards.

I would think so as well. In fact all other adjustable neck joints I recall either have floting necks or like Talors uses shims and hard botls the extension to the body.

I recall reading back in the day where Bob Taylor responded to the "dovetail is better than bolt-on butt joint" argument (Taylor was using just the butt joint then, not the NT technology they have now)...all the dovetail guys were praising the solid, glued-in, contact with the neck block, better vibration transfer stuff and putting down the hardware, "tenuous" butt joint, the "poor transfer" of sound & vibration...all that...Bob says, "Well, there's the "duh" answer....HOW DOES IT SOUND? Pretty much said it all! And not knocking the traditional, but the bolt-on is just so much more luthier-friendly than the dovetail at the beginning and throughout a guitar's life (IMHO)....

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