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For those of you who use a mortis, how much wood do you leave on each side of the tenon? Does a wider block help stability in the upper bout?
B


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On non-cutaway guitars, 1 1/4" on each side. On cutaway guitars, 1 1/4" on the non-cutaway side and, on the cutaway side of the block, 11/16" + or - a bit depending on the width of the fretboard at the body.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Mine are 2 3/4” cause that’s why. No matter style of attachment.

Mine look like this. I make them about 2-5/8 to 2-3/4" wide. The reason is most of my fingerboards are 2-3/8" at the 14th fret. That means that the block is a little wider than the neck heal and the finger board. That give me good base to attach the neck to the body.

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Joe Beaver
Maker of Sawdust

We use a 1-3/4" depth by 3/4" wider-than-body-fret width at body (but not less than 3" width for standard guitars). We also use a chamfer on the unglued edges of the block and an elliptical or otherwise abbreviated and tapered UTG on non-vintage work to spread the loads in the neck area across the top to the bracing and rim.

Another option to address the shear loads (due to dissimilar rates of movement on the fretboard versus body seen on glued extension guitars) is to use a friable or low strength adhesive such as Elmer's Glue-All. This ensures a low strength bond that acts as a fuse by allowing the extension to separate from the top before the top cracks, protecting the structure at the expense of whatever stiffness contribution comes from a rigid, not-creeping joint glued with hide glue. Mr. Proulx uses this approach with some success.

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For the times they are a changin'

- Bob Dylan

FWIW. Since I build ukes that have narrow FB , I make my necks from laminated soft hdwd plywood.Titebond to laminate the ply block. We use fish glue , fast tack, and easier to remove to glue it down and for future repair. If the fb is e,g 44mm wide at the body joint we will use a block 42 mm in width to prevent cracks. I prefer plywood as IMHO as there is less seasonal movement .

I go with 2 3/4" regardless of attachment. These were made today.

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Blue Ring Acoustics
blueringacoustics.ca

Ernie, your neck blocks are less wide than the fingerboards passing over them?

Yes ed they are for our ukes. The Fb is almoost in a straight line to the top of the uke bridge , and it is only 3/16 in or 4 .5mm. in thickness. This allows for a variation in neck thickness and shape . Ukes are light . so there is not as much pressure exerted on the neck block as in a guitar . On the soprano, concert and tenor models , the FB sometimes only goes to the 12 th fret which means just a small section of FB is hanging over the top and upper neck block area . I also shy away from using hard fb/s like ebony preferng rosewood . hard locust and persimmon, these woods are accesible
here , but not so mjuch in Van.Furthermore. by using fish glue . we get a fast tack to center the fb and clamp. If Problems arise, the fb can be taken off and easily replaced or repaired if necessary . Have not seen any cracking around the soundhole. I have built at least 75 ukes. I cannot say if this would work on a guitar. because guitars and ukes are similiar and different in a number of ways . As always experiment on scrap. Bon chance

Guitars get a much wider block for cl and ss. Usually a laminated ply or bass or willow and ply on top and bottom