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Building The FIDELCO Ukulele. Specifications: Solid Mahogany Soprano Ukulele, 13.5” Scale Rosewood Fingerboard with Mother of Pearl Diamond Inlay, Black/Ivoroid/Black Rosette, Rosewood Bridge, Reclaimed Corian Nut, Rosewood Headstock Veneer with Mother of Pearl Logo and Shepherd Inlay, .
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Building The FIDELCO Ukulele Specifications: Solid Mahogany Soprano Ukulele, 13.5” Scale Rosewood Fingerboard with Mother of Pearl Diamond Inlay, Black/Ivoroid/Black Rosette, Rosewood Bridge, Reclaimed Corian Nut, Rosewood Headstock Veneer with Mother of Pearl Logo and Shepherd Inlay,
The Top and Back The entire uke is constructed from reclaimed mahogany from a local plaque manufacturer. At one time, these plaques were being cut up and sold for firewood. One plaque will yield three top and back plates. The plaques are ripped down the center then resawn on a bandsaw so that they can be bookmatched. The edge is planed and the halves are glued together. After drying, they are ran through a thickness sander which reduces them to .080 of an inch. A much better use than fuel to roast a wiener.
The two pieces of wood are scrutinized to determine their best use. Ideally, the grain on the tops should run on the quarter, meaning that the grain is perpendicular to the top, which adds stiffness to counter the tension from the strings. Using a plexiglass template, the shape is traced onto the top and back paying special attention to match the template centerline with the joint that runs down the center of the plate. Once traced, its back over to the bandsaw where the plates are rough cut to shape.
The center of the soundhole is located on the top and then goes to the drill press where the channel for the rosette and the hole itself is cut using a circle bit.
The soundhole isn’t cut completely out on the drill press but just deep enough that it can be finished with a sharp knife. This reduces the risk of tearout around the soundhole. The channel for the rosette is .050 of an inch deep but once installed, it will provide further reinforcement to the soundhole.
Once the channel is cut and the soundhole is cleaned up, it’s time to install the rosette. The rosette is made up of a piece of ivoroid that is .050” thick surrounded with two pieces of black binding that are .020 inches thick. The trick is to get all three pieces pressed into the channel at the same time. They strips are fitted and the ends are trimmed then re-fitted and trimmed again and again and again until they are perfect. Sometimes it takes 15 minutes and other times an hour. Luckily, I only had to start over once on this one and it took about twenty minutes.
Finally, the glue dries and the rosette can be scraped flush with the top.
The bracing location is mapped out on both the top and back plates. The bracing provides support as well as a degree of mass that affects the final tone. Instruments with stiff, or heavy braces, tend to sound a bit thinner and tinny whereas a lighter setup will give it a nice tonal balance across the strings. Too light and the top will sink.
Here is a close-up of the braces. They are carved using a chisel and finger plane so they resemble a pyramid with a slightly rounded peak. They are then tapered on the ends. The kerfing and sides of the uke will be notched so that they are tied directly into the sides of the instrument.
All the braces are installed plus the rosewood bridge plate that sits underneath the bridge and supports the shear tension from the bridge, as well as helps spreads the vibrations of the top to the sound chamber. They will be set aside while work on the body begins.
The sides are bent in a mold using a silicone heat blanket. Before going into the mold, the book matched sides are taped together, wetted and wrapped in foil. The blanket heats the wet sides which creates steam and makes them pliable to mold them to the shape in the bending jig.
A heat blanket is put on top of the sides then they are sandwiched between two pieces of stainless spring steel. Along with holding the sides to the shape of the mold, the steel also helps distribute an even heat. As the sides become pliable from the heat, the waist is clamped down using the handle attached to the large steel pipe at the top of the bending jig. Slowly, each side is pulled down and hooked to a spring that runs under the jig that will maintain tension on the sides and hold them to the mold. The sides are heated and cooled several times to “set” them to the final shape.
So, here they are. As you can see, they are perfectly matched sets. They will be trimmed to length then put into a mold where they are glued, tapered, kerfed and the tops and backs attached to create the sound box.
The sides are put into a female mold so that they will maintain their shape while further work is done.
Traditionally, the ukulele has a tapered back. The sides at the neck block is 1 13/16” then increases to 2 1/8” at the tail block. The taper is achieved by angling the body in the jig then cutting it with a fine kerf saw.
There are two more things to do before gluing the top and back on to complete the sound box. First, the neck block, which will be the point where the neck joins the body, and the tail block need to be installed. They are sanded to match the rounded profile of the body, glue is applied and they are clamped on the centerline.
Next, the kerfing, or lining, is installed around the edges of the sides. This provides support as well as gives a larger surface area for which to glue the top and back plates. The kerfing is notched so that it can follow the curves of the instrument. Below, the mold is sitting on a piece of sandpaper that is glued to a smooth piece of marble. Before, and after, the kerfing is installed the sides are sanded level and square by rubbing them over the paper while in the mold. Once all the kerfing is installed it will be time to glue on the top and back plates.
Normally, I use spindle clamps when gluing up an instrument, but since a uke is so small I find this a much easier and quicker method.
Once the glue is dried then the edges are routed flush with the sides to prepare it for binding.
This instrument will be “side” bound using rosewood with a white/black/white accent strip. Its called side binding because the accent appears on the side of the instrument versus the face. First, a channel must be routed around the top and back that is the width and depth of the binding. When routing the binding channel, you remove so much side material that you reveal the kerfing.
Since the binding is wood, it is bent to shape using the same method as the sides. It is trimmed and glued into the channel. Tape is used to “clamp” it into place while the glue dries.
Since this was a special commission, I decided to incorporate the side binding effect in the tailpiece strip. It took several attempts at this to get the miters matched up but I think it is well worth it.
Finally, we have a sound box and we can start building the neck.
First, two pieces of mahogany are glued together to make the neck blank. The profile of the neck is drawn onto the blank and cut out using the bandsaw. “Wings” are glued onto either side of the headstock area to make it wider. The centerline is drawn on the blank on all sides along with the tapered fingerboard and the headstock shape before being cut to size on the bandsaw. Once again, reclaimed mahogany was used to make this neck, and the blank was large enough for two necks and a couple neck and tail blocks.
Once the neck is roughed out then the heel,where the neck meets the body, is drawn on the end of the blank then cut using a handsaw. Finally, a “heel cap” made of rosewood is glued on that will match the binding that runs around the back edge of the body.
Carving a neck, especially a uke neck, is a pretty simple process but most first timers are terrified that they are going to take off too much material. I like to draw a tapered line off the centerline the length of the neck. At the heel, the line starts 3/8” from the centerline then tapers in to 1/4” just below where the neck meets the headstock. The lines give me something to track my progress with and to make sure I’m doing the same thing on both sides of the centerline. I don’t use a fancy jig to hold it, but simply clamp it to a workbench where I’ll rough carve it using a coarse rasp.
The neck is carved at a 45 degree angle to the first line. The outside will be worked down within 1/4” of the fretboard then I will start blending in the heel and headstock for a smooth transition.
Next, I carve to the center line and try to leave a bit of a ridge right down the center. I am used to carving necks for mandolins, which generally have a rounded V shape when finished, and I like to do the final shaping of that V with sandpaper. At this point, I am working from the outside to the center but carving in line with the neck. I can feel, and barely see, the last pass with the rasp and try to overlap each pass halfway until I have the rounded shape I am looking for. Once there, I will finish out the transition areas at the heel and the headstock and then go over the entire neck with a finer toothed file to smooth out the grooves from the rasp.
After about thirty minutes of carving and thirty minutes of sanding, we have a finished neck ready for the fretboard to be glued on. This particular fretboard was made by a friend, and fellow luthier, David Gill of Columbus, IN. I had run out of rosewood and asked if he had some I could use and he was kind enough to cut, inlay and fret this board free of charge. Surprised is an understatement when I showed up at his shop expecting to pickup a rough piece of lumber but got this instead. He cuts the inlay pockets, along with the pearl diamonds, by hand so he is a better man than I as you will see my solution once we get to the headstock inlay.
Most production ukes have a flat neck heel and body shape to facilitate a quick and easy neck join with little labor. Really, really high end builders use a compound dovetail joint which can literally take hours to cut and fit. I like the look of the rounded body profile that you get with the dovetail but use a reliable and easier dowel system in joining the neck. Here, the body profile was traced onto a piece of paper which was then glued to the top of the neck(before the fingerboard was glued on). Using a spindle sander, the heel was sanded to fit the body profile. A little more hand sanding will make the neck so that it attaches with about one degree of neck angle. When the instrument is tuned to pitch, the string tension will decrease the angle making the neck almost parallel to the top. Otherwise known as creating neck relief.
Here the headstock veneer, with mother of pearl inlay, is being glued on using my parrot vice as a clamp. The fretboard was glued on prior to this step. Once the veneer dried, the tuner holes were drilled and tapered for the bushings. You can catch a glimpse of my name and the special logo I had cut specifically for this project. It’s a really cool looking inlay.
Here is a shot of the neck joint. Corresponding holes are drilled in the neck heel and the headblock of the body. A 3/8” dowel completes the joint. The dowel and the mating surfaces will be glued. It is a very simple, yet reliable joint that has been used for decades. A lot of people look at this and say, “Wow, how in the world do you clamp that together while it dries.” Easy answer. Rubberbands. Very large rubberbands.
Nothing like two 40” rubberbands wrapped in every conceivable direction to get the job done. Once stretched, these will provide as much, if not more, clamping pressure than most clamps. These are also used to clamp fingerboards, binding and other odd shaped assemblies.
