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Uke observations
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=40898		 Page 1 of 1
Author:  Beth Mayer [ Tue Jul 16, 2013 4:00 pm ]
Post subject:  Uke observations
Hi all,

Just got back from Maui and Kauai. Very beautiful and fun. While on Kauai, I went to all 4 musical instrument stores I could find, to handle and play some ukes. Figured I'd never see as many in one place again, and that's probably true.
I played a couple of Kamakas, a Ko'Aloha, a local builder (can't remember his name), and several Kala's (I think these are imports) and a few other imports.
I was surprised to find that even some of the more expensive instruments had visible squeeze out inside, and most used Grover tuners (nothing wrong with these, but I guess I expect to see higher end tuners on some of the big ticket ukes).

I was looking mostly at Concert size, and the one that sounded the best to me had some features that surprised me. The 13 fret to neck, concert Ko'Aloha had decent straight-grained Koa - pretty enough - and a lighter Koa fingerboard. It had some friction peg tuners that I'm guessing were Grover or equivalent.
Most interesting to me, and unique to all the ukes I looked at, it had no linings. There was a brace at the waist, which looked like a 1/4" piece of wood, cut to fit so that top, sides and back are all glued to it's "rim" (so it's like a partition between the upper and lower bouts) , and with most of the inside cut out. There was also a transverse brace above the sound hole. There was no back reinforcing strip or any back braces. They were two piece top and backs. That thing really rang out.

What I didn't like was the finish looked heavily sprayed and plasticky, and they sprayed the bridge, (which was the same size you'd put on a soprano with no wings), which I thought made it look like a toy. Also didn't care for the plastic nut and saddle. It sounded so good, I was going to buy it, but I could not bring myself to give the horribly pushy, aggressive and condescending owner any business. But that's a different issue. Too bad too, because he had it for sale far below price I found on line.
After all this rambling, I wonder if any of you has any experience with this kind of construction. It seems like you'd need to have CNC capability to perfectly fit this one structural brace/gluing surface. Also wonder if the brace described makes up for the tiny gluing surface of sides to top and back without linings. Maybe the sides were thickly laminated, but it didn't seem so. I have heard of someone not using linings on a soprano, but what about the bigger uke sizes which have a little bit more string tension?
I really want to make a uke that sounds as great as this one did, but not sure I could follow this construction method. I'd be interested in any thoughts about this type of design, or how you would modify it. Aloha!
Author:  Michael.N. [ Tue Jul 16, 2013 4:17 pm ]
Post subject:  Re: Uke observations
All said and done Ukes are fairly low tension instruments. When I make a Vihuela or Baroque Guitar I don't use linings Top or Back. No reinforcement on the Top centre joint, just two Bars either side of the soundhole. The combined tension of the strings on these instruments is a lot greater than found on a Uke. In fact I'm pretty surprised how over built many Ukes are. I'm also surprised that there's any soundboard bracing at all but then again what do I know about Ukes.
You certainly don't need no CNC to fit a brace!
Author:  Dave Higham [ Tue Jul 16, 2013 4:51 pm ]
Post subject:  Re: Uke observations
You didn't see any like this then?

http://www.moorebettahukes.com/MYWORK.html
Author:  ernie [ Tue Jul 16, 2013 6:58 pm ]
Post subject:  Re: Uke observations
interesting way to make ukes at the source i.e. hawaii. Have a whole bunch of interesting videos on making ukes for those who are interested www.ateliertomistrings.com
Author:  Beth Mayer [ Tue Jul 16, 2013 7:13 pm ]
Post subject:  Re: Uke observations
We did not go to the Big Island or Oahu, so I didn't get to see any makers or their shops (I did go to one makers shop which I won't name, but can not say I was too excited about those ukes).
Michael, if you had seen this weird brace, you'd know what I mean about making the brace with CNC....I think it would be challenging to make it all work if that brace isn't really standardized (for lack of a better word).
I know that I have been building lighter and lighter on my ukes with each one, and they are still overbuilt. I started out using the Hana Lima plans for thicknesses and for bracing and reinforcement. I'm gonna be really spare on the next one and let the chips fall where they may!
Author:  DennisK [ Tue Jul 16, 2013 7:23 pm ]
Post subject:  Re: Uke observations
The squeeze-out is probably intentional. I've heard of it being used as a sort of miniature lining on old baroque guitars and such. Hide glue is brittle, but at such small size would probably be fine. And even if it does form a few cracks over time, it's still no worse than kerfed linings/dentellones with spaces between them.

I have thought about doing a braceless uke back... but if I'm understanding properly, there was a full "square" brace at the waist, that glued to the top, sides, and back in this uke you're talking about? I do that at the upper bout on my guitars (big upper transverse brace on both plates, with minimal tapering at the ends, and decently hefty side braces that connect the two). I do it to stabilize the neck angle. Not sure what benefit there would be to such a structure at the waist.

I wonder if the back would be less likely to split with no braces glued to it at all though, since it's having stuff glued cross grain to one side and not the other that induces curvature when the humidity changes.

You might be able to get away with a fully braceless top too, if you use carbon fiber buttresses going from the top side of the headblock to the back side at the waist, and put soundholes beside the fingerboard instead of in the middle of the soundboard. But that forms two triangles consisting of the CF rods, headblock, and the back... and an unbraced back is definitely the weakest link in there, so you might need a cross brace on the back at the wide part of the upper bout to prevent it from deforming and allowing the headblock to rotate. And one across the waist where the CF rods attach, if you want to be really safe.

Definitely easier to put a cross brace on the top at the wide part of the upper bout, and L shaped headblock connecting to it, to take most of the neck torque. And if you put soundholes beside the fingerboard extension, you could do away with all other soundboard braces.

And I agree, plasticky finish = ick, and tiny bridge in the middle of a large plate just looks weird, even if it is structurally fine. Give that thing some Red Bull :lol: (gives you wings)
Author:  Beth Mayer [ Tue Jul 16, 2013 8:24 pm ]
Post subject:  Re: Uke observations
Good observations, Dennis...yes, you are understanding the square brace correctly. It does seem that, in that location below the central soundhole, it would hinder some of the plate movement, but if it did, I sure couldn't hear it. I haven't tried the buttress thing yet, though I did enjoy seeing it in your build and in Burton's build a while back. I was afraid I wouldn't be able to execute it.
I do not believe the squeezeout was intentional. It did not look like hide glue, and I was seeing it on the ukes that had linings...so no good reason for it there. Just looked sloppy inside, and these were supposedly hand made by one guy.
So what about having a cross brace near the waist, a transverse in upper bout, and then no fan braces below, but just a spruce or equivalent bridge patch?
Author:  DennisK [ Tue Jul 16, 2013 9:33 pm ]
Post subject:  Re: Uke observations
Beth Mayer wrote:
Good observations, Dennis...yes, you are understanding the square brace correctly. It does seem that, in that location below the central soundhole, it would hinder some of the plate movement, but if it did, I sure couldn't hear it. I haven't tried the buttress thing yet, though I did enjoy seeing it in your build and in Burton's build a while back. I was afraid I wouldn't be able to execute it.

You must be thinking of someone else, because I've never done the buttress thing either, for the same reason [uncle]

The brace would probably make the back behave more like two small, higher pitched resonators. But that may be better than one big, low pitched energy sink. And then there's the issue that uke backs are damped out by the player's body a lot of the time, so it may be better not to design for an active back at all.

Quote:
So what about having a cross brace near the waist, a transverse in upper bout, and then no fan braces below, but just a spruce or equivalent bridge patch?

Sounds good.

This is my current favorite pattern for nylon string instruments:
Attachment:
SideBraces.jpg

The A-frame performs the same rotation resisting function as an L shaped headblock, in addition to stiffening the soundhole area where the box might try to fold in on itself. That cross grain patch of wood that goes underneath the headblock supports against the longitudinal pull of the neck, although it's probably overkill with the A-frame also doing that job. The cross grain strip in the lower bout is just a crack catcher, probably not necessary at uke size. Even the A-frame probably isn't necessary at uke size. Just two cross braces and call it done.

I'll probably do two cross braces plus A-frame whenever I get around to the concert uke on my agenda, just because I'm paranoid about neck resets, and I don't believe the soundboard area above the lower cross brace has much effect on tone either way. And I'll be using either lutz or giant sequoia, both of which I have riftsawn tops, which makes softwoods extremely flexible across the grain. Should somewhat mimic the long grain to cross grain stiffness ratio of a thinner quartered top with fan braces. But that coral snake guitar is perfectly quartered redwood, very stiff across the grain with no fan braces, and it sounds excellent. So for sure both ways work... it will just be fun to explore the differences between them more :)
Author:  Michael.N. [ Wed Jul 17, 2013 1:15 am ]
Post subject:  Re: Uke observations
Me thinks you are over thinking this. Just do the two harmonic braces either side of the soundhole. That's it. Nothing more needed and certainly not for a Uke.
Do a Youtube search for 'Brune 1863 Torres'. He talks about a very simple Torres Guitar without bracing:

Image

That Guitar has WAY more tension than any Uke.
This is how I do a Renaissance Guitar, which is really the original Ukulele except that it's a long Ukulele. Probably longer than a baritone.

Image

With a Uke you probably need 2 Back bars at the most! Linings certainly not needed. I'm pretty sure I could build a modern Classical Guitar without any Linings and it will still be fine. Uke's, definitely not necessary. Many Ukulele makers take their ideas from modern Guitars ,hence all the crazy bracing patterns that you see in some Ukes. But Ukes are nothing like modern Guitars. They are much closer to a renaissance Guitar than any modern Guitar - both in tension of the strings and the actual musical pitch. They even have a version where the strings are doubled, the Taro patch. It's a renaissance Guitar.
Author:  PeterF [ Wed Jul 17, 2013 4:00 am ]
Post subject:  Re: Uke observations
Would you be able to bind a uke with no linings or do you leave the binding out?
Author:  Michael.N. [ Wed Jul 17, 2013 4:54 am ]
Post subject:  Re: Uke observations
No you can't bind it but you can half edge it.
Author:  ernie [ Wed Jul 17, 2013 6:55 am ]
Post subject:  Re: Uke observations
I use 3/16in /4.5mm WRC kerf binding on my ukes . as the binding/purfling adds a vy decorative touch IMHO.Only problem is sometimes the binding does not want to behave around tight curves e.g. Honduran rw , so I try to make it thin around .060 or abt 1.5mm.
Author:  Tai Fu [ Wed Jul 17, 2013 8:22 am ]
Post subject:  Re: Uke observations
The uke I am building has been very lightly built intentionally. Last sophrano was a disaster because it was way overbuilt. I guess I tend to overbuild everything just because I am scared of failure... You can always tone shape it later on if it seems overbuilt but if the instrument breaks because it was underbuilt, then you've lost all your hard work.
Author:  Pmaj7 [ Wed Jul 17, 2013 11:38 am ]
Post subject:  Re: Uke observations
I think you certainly could build a uke without any linings, reinforcement strips, braces, etc. But it would be better to just make really small reinforcements.
Author:  profchris [ Wed Jul 17, 2013 2:29 pm ]
Post subject:  Re: Uke observations
I've made around 25 ukes, mainly sopranos, and I think I'm now getting the hang of it. My aim is to build as light as possible, so that the back and sides are live and contribute to the sound.

Linings are not strictly necessary, but to compensate for any poor gluing technique on my part I use a tiny lining 6mm deep and 1.5mm thick, about the same thickness as the sides. If I'm binding, I use a double lining.

My body shape is very narrow, based on that used by the Portuguese immigrant makers of the 1890s, and I use only a single top brace between just aft of the soundhole, plus a bridge plate of the same material and thickness of the top. The back has a single brace at the waist.

I've recently started putting a very noticeable curve to the back, and this makes a huge difference in both volume and resonance. This is a koa soprano which I finished recently (all koa except for the Spanish Cedar neck), and it weighs in at 230 grams. It's about as loud and resonant as the Koalohas I've played.

Image
Image

For a full-width concert I'd probably use a second top brace in front of the soundhole and two fans, but stick to a single back brace. Braces are 6mm or less wide, around 8mm tall, and tapered to nothing at the sides.
Author:  Beth Mayer [ Wed Jul 17, 2013 2:41 pm ]
Post subject:  Re: Uke observations
Great information, all. Thanks for the input! When the next one is done (I'm in the middle of a guitar build right now), I'll post it and compare with the one I just finished.
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