Cocobolo + Spruce Concert, First build

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Chris_H

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Here are some pics of the first uke to be shaping up in my shop..







After I joined the soundboard to the body, I realized the braces were too heavy. After they were trimmed much further, the tap tone of the body so far, gained a lot of depth. I am a little scared to trim the braces further, though they probably could take it. Next time round I will make a heavier lining, this profile seems weak and small. I will likely add some small discreet tabs to reinforce the bracing, especially since the top will have a 2-3mm band of shell purfling.
This uke will be bound in Bocote. I love this Cocobolo, it is from some veneer I cut about 5 years ago, leftover from a project.

Might do a Bocote fingerboard, not sure yet. Neck is Spanish Cedar. This one will be a bolt on neck.
 
Bracing is all glued with HHG, except for the back which is glued with Titebond 3. I did a break test with HHG and Cocobolo, I like Titebond 3 better here, not enough experience w/ HHG to trust it yet. Love HHG for other stuff!

Sides are currently about .080" Top is about .080" Back is about .075" I will probably remove quite a bit in the finish sanding of the back and sides.
 
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Is it together yet? If not trim those top braces right down.... Bridge patches on mine are always softwood when I do a spruce top instrument; just like classical guitar makers.
 
Beautiful single piece of wood for the back. nice inlay too. What are you going to do for the headstock?
 
Pete Howlett said:
Is it together yet? If not trim those top braces right down.... Bridge patches on mine are always softwood when I do a spruce top instrument; just like classical guitar makers.
Click to expand...
Thanks for that Pete... No it is not together yet. I just mixed some T-88 epoxy with some fibers into a paste, and delicately filled some 'tabs', in the kerfs of the lining. I do not trust this stuf as much as I would like. I was pretty tidy with the filler, and barely applied any, but feel like I added some integrity to the lining strength. Chalk that one up to a learning experience. You must mean the upper 2 braces... I was wondering about them. I left them heavy, thinking that there might be some stress due to the neck, but will trim them further. Yes, the bridgepatch is Rosewood, guess I should have used Spruce. Thought about CF for the bridge patch, but decided against that, think I will stiuck with wood there. Will do further research on materials for here..

vanflynn said:
Beautiful single piece of wood for the back. nice inlay too. What are you going to do for the headstock?
Click to expand...
Thank you. Not sure what the headstock will look like yet. Still contemplating slot head, or the other style. Not sure for veneer either. I have some cool fingerboards, but have not yet decided, and this will influence the headstock finish. There will be shell, shell on the fingerboard too... Fully aware that I may make it to 99% and end up destroying this by accident... fingers crossed!
 
Pete, do you mean, also, the braces over the bridge patch?
 
The work looks good Chris but as with most beginner ukes it looks WAY over built. With that large and heavy of a bridge patch you could almost forget the fan bracing all together, especially with a .080" top. They get better with each one you build. Good, clean work though.
 
Cool, thats what I need to hear... I realized the bracing was probably too much, but having no experience, did not want to end up with too little. I will do my best to make the braces disappear before closing this one up. It is interesting contemplating the learning curve. I have built over 700 of one of the types of tuyrntable plinths that I make. It took me around 100 plinths to even realize some things that are critical to the performance of the plinth, about 500 to start to see a more complete picture of how all the measurements work together, and finally, I have more of a handle on making high quality plinths. With the ukes, I know it is just time to put in the time, do my best, and be patient. I see that 'hit and miss' is going to play a significant role for a long time.

Can't wait to have a uke to play though!....
 
And it's going to be a beauty! Please post plenty of pictures so we can all learn from your experience.
 
like others have said, too heavy on bracing. Many of us won't use Titebond 3 as it never really gets hard and you can get creep that shows thru the finish. I have had direct experience with this with cabinets i have built. It is real. You want the original type 1 with the red cap. Very nice first effort in general.
 
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Michael Smith said:
like others have said, too heavy on bracing. Many of us won't use Titebond 3 as it never really gets hard and you can get creep that shows thru the finish. I have had direct experience with this with cabinets i have built. It is real. Very nice first effort in general.
Click to expand...

I am familiar with the 'creep'. I use T-3 in my plinths for it's strength. To deal with the creep, I add about 2 months waiting time for the glue to cure, and try to ensure absolutely tight glue joints. For thew most part, this solves the creep problem. In this application on the uke, it is present only back to lining, and will have no exposure to the exterior. Yes, I can see T-3 causing absolute disaster with the finish on an instrument.... build, finish, polish, smile..... then watch the glue line pop up a month later, a big fat ridge in the finish.

This does bring up an uinanswered question though... as to what glue to use for the bindings. They will be Bocote, gluing to Cocobolo. I want some structural integrity here, as well as just holding the bindings in place. Was thinking about the LMI white glue, but would love suggestions from experience.
 
I agree with what the others said - clean looking build, and it even appears to be symmetrical! Not bad at all. My first thought when I saw the pics was that the kerfed lining strips looked big, then I read you don't trust them. I'd trust them after reducing the width quite a bit. I buy the mandolin linings from stewmac cos I'm too lazy to make my own, but I plane them down between the end block (if I even use one) and the brace beneath the sound hole. I figure that by thinning them say 2 mm gives me a soundboard that's 4 mm wider. Takes about 60 seconds and it works for me.

You already got feedback on the braces, so I won't repeat it. So I'll just repeat that I think it looks good.

Sven
 
Before

And after..

The tap tone resonance of the body has changed considerably, sounds and feels a lot less like a brick :)

The bridgeplate is .090" thick, too thick, and too big..

And the back is now joined with the body. I do not have a clamping caul made for this yet. The go bar rods were purchased from Goodwinds a kite supply store in Washington. 4' lengths of 3/16" fiberglass cost around $125 each. They also sell the plastic end caps, also inexpensive.
 
Wow, the kite suppy store is a great idea! I will have to try that. But at a total of $2875 for a set of rods, I may have to save up for a while!;)
Just kidding. But seriously, that wood looks right pretty.
 
Chris,

Great looking work and thanks for posting. The replies from the experienced luthiers is helpful too. We are all learning together.

All the best and I hope you post a sound clip when you are done.

Tom
 
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