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Leftypeter
01-31-2016, 06:56 PM
I am building a tenor uke 17 inch scale and wondering if neck reinforcement (perhaps graphite rod?) is necessary or overkill. Built one guitar but this is first uke.

Also, is bolt on neck with threaded insert a good choice for neck to body join? Dovetail joint seems hard and time consuming.

What a great resource this forum is!

BlackBearUkes
01-31-2016, 07:17 PM
A graphite neck truss rod is a must in my book. Of all the ukes sizes, the tenor when tuned to standard GCEA, has the most stress on the neck. My advise is to use a truss rod. I don't do bolt on necks so someone else can chime in on that point.


I am building a tenor uke 17 inch scale and wondering if neck reinforcement (perhaps graphite rod?) is necessary or overkill. Built one guitar but this is first uke.

Also, is bolt on neck with threaded insert a good choice for neck to body join? Dovetail joint seems hard and time consuming.

What a great resource this forum is!

granger
02-01-2016, 03:40 AM
There have been some good studies done on this that make me feel that a carbon fiber truss rod is a must. I use 1/8" x 3/8" that I get from Stew Mac. I use a bolt on neck with a reverse heel. This design was inspired by the Tacoma Papoose, an excellent instrument. It is very easy to make a jig to route a pocket into the reverse heel neck block and then fit the neck tenon into it. The real beauty of the design for an amateur builder like myself is that allows me to fine tune the neck angle. And I have found I can adjust the neck angle very easily after the instrument "settles in". When you set the frets into the fret board slots you cause the neck to want to bow back, once it is strung up for a couple weeks under tension I find that the neck comes back to where it wants to be as the tension compresses the barbs on the tang of the frets into wood of the fret board slots. An highly experienced luthier must know how much to compensate for this on a glued up neck, I don't so I appreciate the ability to reset the neck with a bolt on design. I am fussy about having the action as perfect as possible on my instruments and the adjustments that you make with a reverse heel design are all in the same horizontal plane. By putting in a temporary shim into the neck pocket you can see how it affects the neck angle. I stack up pieces of tin foil. They are .001" thick. A stack of 10 of them in the rear of the neck pocket can make a big difference in neck angle.

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mikeyb2
02-01-2016, 06:58 AM
Peter, I recently started a similar thread, and decided to use a shortened graphite rod as shown in the Mya Moe video on Youtube. I also decided to use a threaded insert and similar socket bolt to join the neck to body. This is where I am at, on my first build. The connection when tightened up as in the photos seems very secure. I have used a similar connection on 3 banjos, and had no problems.8794487945

Leftypeter
02-01-2016, 07:00 AM
Thanks for the wonderful detailed feedback. Looks like I will go with the graphite truss rod. Does Stew Mac make them specifically for ukes or do you modify one meant for guitars?

Michael Smith
02-01-2016, 08:17 AM
I use the carbon fiber 3/16" x 1/4" x 24 cut in half to fit from LMI. It is my belief if you put in a half a dozen thousands relief in your neck and expect it to stay for the life of the instrument carbon fiber can only be helpful.

mikeyb2
02-01-2016, 09:24 AM
Thanks for the wonderful detailed feedback. Looks like I will go with the graphite truss rod. Does Stew Mac make them specifically for ukes or do you modify one meant for guitars?
I bought mine as carbon fibre guitar rod 8mm x 4mm and cut it to length( I'm assuming graphite is the same as carbon fibre in this instance)

Beau Hannam Ukuleles
02-02-2016, 03:52 AM
I am building a tenor uke 17 inch scale and wondering if neck reinforcement (perhaps graphite rod?) is necessary or overkill. Built one guitar but this is first uke.

Also, is bolt on neck with threaded insert a good choice for neck to body join? Dovetail joint seems hard and time consuming.

!

A bolt on neck is a good traditional choice.

use either a CF rod (best) or a stick of ebony as neck reinforcement