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I am getting ready to build a uke with as much sustain as I possibly can. This instrument will be mostly played in a slow, melodic finger picking style (Think of John King or Daniel Ward). This is the first time that I’m building a uke with such a purpose in mind and I would like to get some feedback from those who have built a uke with sustain as the overriding goal before.
In particular, I would like info/suggestions on the following:
1. Top Wood
2. Back and Side Wood
3. Bridge
4. Bracing
5. Bridge Patch

Anything else you have insight on would also be appreciated.
Many Thanks!

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Formerly know as Mandodiddle.

My Ukulele #7 has an Englman top, it has some of the longest sustain Ive ever encountered in a Tenor sized Uke. The bracing on it is Kasha though

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Steel strings I love my harp ukulele.

You could try a double back (where the external back that rests against your belly is stiff and heavy, but there's a second lightly braced back inside to vibrate). Or sympathetic strings like Fred Carlson's sympitars. Maybe nylon playing strings and steel sympathetics on an internal zero-downforce bridge so you can still brace it like usual.

Ukuleles ain't what they used to be...
Sustain was not a particularly desirable feature for the "bouncing flea" sound when all Koa wood bodies were de rigueur.
But then came Jake Shimabukuro.....
https://www.youtube.com/watch?v=IYhcN8p ... zw&index=2
https://www.youtube.com/watch?v=rxzqlzU ... w&index=11
https://www.youtube.com/watch?v=1UM7CXj ... zw&index=3

You definitely want a softwood for the top. I'd guess that a good, stiff piece of spruce might top the sustain table. Light + stiff is more important than species.

If this is a tenor or concert, use simple fan bracing and no bridge patch. For a soprano, two ladder braces and a very thin spruce bridge patch.

I find that slightly thicker tops enhance sustain, but at a small cost in volume. The trade off is inevitable. Light bracing is important.

Body is less critical, but rosewood might offer a little more sustain.

Another thing that helps sustain is a greater impedance mismatch between the bridge and top - the energy is transferred more slowly over a longer period. A dense bridge material (African blackwood) on a spruce top? Since the same amount of energy is transferred over a longer period of time initial volume is less.
Ukes are not terribly loud instruments, so the loss of volume for the increase in (less audible) sustain may not be a perceivable benefit. YMMV

I'm not familiar with kata bracing. Do you mean Kasha?

Build it like a guitar, except the bracing. Spruce top, hardwood back and sides, etc. Brace it for high tension strings like Savarez Cristal 500CJ and Alliance 544J. Pretty much standard fare for me, as your goal is the same as mine.

Thanks everyone. I'm definitely thinking about a light and stiff spruce top now. Maybe go with Rosewood on the sides. The bracing and the thickness of the top is still up in the air for me. I'm getting conflicting opinions from other sources as far as making the top thin as possible or thicker than normal.

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Formerly know as Mandodiddle.

Thin tends towards less sustain - think banjo.

But I'd aim for just a little thicker for the top, a hair over 2mm. Too thick and the top is too heavy to work properly.

For comparison, a hardwood top will be 1.8mm or less, depending on stiffness.

Two things I'll add to the list of good suggestions already posted:

1. Increase stiffness and mass of the neck. Stiffer materials, bigger cross section, the addition of a trussrod or other metal stiffeners if you don't already use them. This will help reduce losses to the long archery bow-like bending mode of the instrument.

2. Increase scale length, or just use the longest scale length typically used for the size of the instrument. If this is done using a conventional string set, this will increase static string tension which may require stiffening of the top structure. Longer strings require less bending for a given picking displacement and are subject to less internal damping. Longer strings are more compliant and allow greater picking displacement as well.

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R.M. Mottola
LiutaioMottola.com

Author of the books Building the Steel String Acoustic Guitar and Mottola's Cyclopedic Dictionary of Lutherie Terms.

Want more sustain? Just build it like this instrument from Nigel Tufnel's collection:

https://www.youtube.com/watch?v=lrhJv4KplU4

OK, back to the real advice.

[FACE WITH TEARS OF JOY] Those were the days. Good old Spinal Tap!


Sent from my iPhone using Tapatalk

_________________
Formerly know as Mandodiddle.

Darrel Should read as Kasha bracing

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https://www.facebook.com/PuraVidaUkuleles/