Scarf Joints

vanflynn

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I’m starting a Hana Lima 'Ia kit to help appreciate what all you folks do and have a question about the scarf joint. Does it really matter if you cut the joint so the head stock is on top or on the bottom of the neck (alt in pic)? The instructions have you put the headstock under the neck but that makes the joint line visible on the headstock and I wasn’t planning on putting a veneer on it.
(Of course I am assuming that this will end up as a playable instrument instead of expensive firewood!)

Thanks

Scarf joint.jpg
 
the middle one is best
 
my apologies on the link. Wan't sure that would work.

Go to Advanced search - enter Scarf under jeywords - to the right "seach titles only"
I got several pertinent hits.
 
Usually with the type of joint used in #2, "ears" are glued onto to the sides to hide the joint.

I've been making scarf joints that way for years - once I tried to test a dummy neck "to destruction" by clamping the headstock in my vice and bearing down on the neck with all my strength.

I failed to break it, so I recommend the #2 design, with "ears" either side. As for the visible glue line - I like to see this. Wear your joinery skills with pride!
 
I dont like scarf joints in necks..I usually make e'm one piece...otherwise I build them laminated out of 3 or 5 slices ...Much stronger and less chance of warping (sometimes with an ebony stripe down the middle) :)
 
Early in my career I made a couple with the "wrong" juxtaposition, and sure enough, one of them came undone. Perhaps both by now. The problem is that all of the tension goes to that iddy bitty point of the joint on the back of the neck surface, and if there is any weakness it will simply unzip.
 
I always do the middle style. All 3 styles are fine foe ukes though. Go with what works for you and your neck blank
 
#1 is used by a jillion electric guitar makers. Once the neck is carved the joint ends roughly under the first fret, in plain sight. No one seems to care. I've used both patterns for hundreds of necks with no problems, but I prefer #2 because the joint can be hidden with ears and veneers. #1 comes apart more easily if the instrument is dropped, but with a uke you'd have to throw it on the floor pretty hard to break the joint. Long ago I made test necks out of pine to test the joints, then beat them on the concrete sidewalk until they broke. The necks broke, but the joints held. But the maple in electric guitar necks seems to be stronger than the glue joint. I've had to repair quite a few, but the break was as likely to include some shattered wood as well as the glue joint. Either way, it was an easy fix.
 
I tend to use one piece but if I am going to use a scarf joint it will always be type #1. Firstly it looks lovely and people think you are really clever for creating that funky joint with all the compound curves (they don't get that it was just two flat surfaces to start with). Secondly the question of strength has never been an issue. It is a Uke, not a chair so I would not expect it to see enough stress to break the joint.
Just my preference.
Max
 
For what it's worth...this is my set up for cutting and gluing #2. I then apply a thin overlay to cover the joint.
 

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Why hide the scarf joint?

A scarf joint is something I proudly point out to customers to show a BETTER build quality. It is NOT a 2nd rate joint or compromise woodworking technique.

I would be more embarrassed about using a one piece neck which as it provides a weak point due to grain orientation under the nut- more chance of the headstock breaking off if the instrument tips over (google Gibson neck breaks). Yes, it is more unlikely on a uke but accidents happen.

On my one piece necks (neck and heel) I still scarf the headstock even though it is more work.
 
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