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Hello,

I’m staring up a new tenor build which will have two firsts for me. It will be the first time using a hardwood top other than mahogany and it will be the first time using an x-brace on a uke. Should be a fun couple weeks. I’ll post pics along the way.





I also made a new bending form and a new form for laminating lining. The bending form is reduced 0.075 from the size of the outside mold. This should approximate my 0.065 side and 0.010 thick steel slat as part of the bending sandwich.

The laminating form is reduced 0.250 to account for 0.180 worth of lining and the 0.065 side thickness (~0.005 ). I’m hoping using this reduced form will let the lining fit better without as much need for clamping.



Brad


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Mighty pretty wood there. Look forward to see it under finish.

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Brian R, Wood Mechanic
N8ZED

An update on where I’m at with this build. The sides are bent and blocks are in. The lining is laminated and cut. The side reinforcement is glued in. The back braces are on and shaped. The rosette is in and the upper transverse is on.











































Brad


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Great looking set, especially the sides. I like your tail block radiusing jig too

Ed

Looks good Brad!

So, you did a full width lining sandwich and then cut it into strips on a bandsaw? If so, did you need to use a caul in the waist or bouts sagitta?

Does your block radiusing jig register somehow on a certain pivot distance from the disc?

Pat

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Pat

Thanks, Pat!

For the lining I use spring clamps. I pretty much use Burton LeGeyt’s exact steps in his solid lining tutorial in the tutorial forum here except I use bias tape for the side reinforcement. For this Uke it’s not a tapered body so it makes it a bit easier.

In terms of needing a clamp at the waist, I’m starting to get that worked out. Initially I was bending the side and the linings sides all on the same bending form. It would work but I would have to torture the lining to get it clamped in place. Recently I’ve been making new molds for all the shapes I build and making them so they are reduced size. What I mean is, I used to make a bending form by taking the outside mold, tracing that shape onto a board and cutting it out to use as the template for making the bending mold. Of course doing that doesn’t account for the 0.075” or so side thickness. Also there is the thickness of the metal slat in the sandwich to add in as well. Mine are 0.020 thick. So what I did was made a bending form template as usual and then use a rabbeting bit to reduce it by 0.095 which gives me space to accommodate my normal side thickness of 0.075 and the 0.020 slat on the bottom of the bending sandwich. So that sorts the bending form for the side.

For the laminated lining, I did the same thing but reduced it down by 0.250” to account for the thickness of the side plus the thickness of the lining strips after laminating them. I use that form for bending the lining sides, I bend all three at the same time, and then use that same form when laminating them together.

It’s not 110% dialed in, but it’s very close and things nest together a lot better now that I’m doing it this way. I did the same for the molds for the last two Dred’s that I finished and they were also a lot easier to fit together. Hope that makes sense.

This is the clamp setup.



Close up of the waist and how things seat together.



Like I said, it’s still a little fiddly but manageable compared to before when I was using one mold.

In the future I want to spend time learning to bend on a pipe. I think I could tweak on the fly if I was using a pipe vs needing so many molds. Maybe not though.

Brad


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Forgot about the block radius jig question.

Yes, I just clamp a straight edge to the table on the sander. Then I have “sleds” for each body type. One end of the sled has the neck block shape, the other the tail block shape. You can see the bar clamped to the sander table which acts as a guide for the plate.



Brad


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Progress on the ziricote tenor Uke from today - The top is braced and the lining is installed. I decided to forego the finger braces in the end. Given the size of the body they won’t be needed.

Wakanda Forever!!
























Brad


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Thanks Brad, but what I was asking about is how you made the linings. Did you make one wide lay up? I was wondering if you had any problems cutting it on a bandsaw. Like did you need to put a caul underneath it?

And for the radius in jig, I didn't see the bar in front of the abrasive. That's what I am making also. I thought maybe you did something like pivot the whole jig a certain distance back to give you that distance of a radius...

Pat

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Pat

Got it, no I just slice it up. The lining is paulownia which cuts so easily there is no resistance on the bandsaw so it slides through easily.



Got it. No, it’s just the front edge of the sled running against the bar. I do want to switch to 120 grit, there is more cleanup of the block than I like and introduces opportunities for me to mess it up.



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Progress from today. The box is closed and the bridge is started. The final bracing measurements are below. It’s ringing and flexing nicely so I went ahead and closed the box.



























Brad


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Progress from today. The neck joint is roughed in. Will floss it and final fit after the binding is done.







A little stub ground to a point that I use to locate the hole in the neck block.























Brad


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A little progress today for Labor Day. The binding is on.































Brad


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Awesome ziricote top! Is that some sort of white gluing caul on the outside of the bindings under the green tape?

Pat

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Pat

Hey Pat,

It is strips of HDPE that are the same size and thickness as the binding. It’s not on top though. I do a two step process, purfling first then binding. The strips act as a proxy for the binding to hold the purfling in the channel while I get it tacked in. Then I untape the strips, remove, and put the actual binding in as a last step.

Brad


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Progress from today... No progress.

But the protective shellac coat made it pretty.







Brad


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Beautiful!

Thanks for sharing the build!

M

I injured my back on Labor Day and just getting back to being able to hobble around the shop a bit. Here is the progress on the latest.

I put the head plate on and trimmed the fretboard to shape.

For the fretboard I use a two step template. First step puts the shape on the end, the second puts the taper on.























Brad


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Frets are in and everything has been final sanded. Pore fill and spraying this weekend.























Brad


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Sweet fretting rig!

Pat

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Pat

In the true spirit of warts and all... I’ll add some pics where I had a failed finish.

The finish bubbled up very much like solvent pop, but what I learned is that it’s air coming to the surface from the heat applied by the UV light. This happened because I attempted to skip pore fill which I now know is a no-no with the UV materials. I stewed on this for almost 3 weeks while working on other projects. It was barely noticeable after leveling but was indeed there. It’s a tricky balance that I’m learning about when to pull the plug and redo something and when it’s fine to let it sail. On this one I want the finish to be perfect so I pulled the plug.





Also made a bridge for it today on the CNC. I’m new to CNC and the uke bridge is one of the first things I drew up in the software. Recently I added an engraving pass at the very end to mark the centerline and the string hole locations. These will get sanded off after the bridge is installed.





Brad


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Good thinking on the markings. Slick!

Pat

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Pat

Sheesh, I work so slowly.

Getting to the buffing stage is satisfying.











Brad


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Wow! That's gorgeous.

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Nearly done. I still need to do a final setup and spit shine.





Brad


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