While working on the jig to bevel the caps and making a test piece I had time to think about making the center bowl that goes in the body opening. I had it narrowed down to a small segmented piece or laminating up a solid blank and using it to turn the bowl. In the end the laminated piece won out mostly due to final assembly considerations when attaching the bowl to the body.
The lamination begins with laying out the leopardwood pieces needed shown in the top photo below. Pieces 1 through 4 are full thickness but 5 and 6 get cut thinner and go in between the outer full thickness pieces. The red arrow points to a faint white line that’s their rough thickness. In the bottom photo the piece in the back is 5 and 6 and has been rough cut to thickness but not to length. The color in the sawn pieces is lighter since the outer oxidized skin got removed when squaring the blank.
The bandsawn face does not look to bad in the above photo but if you get in close as in the top photo below it does look too rough to use as a gluing surface. Smoothing the surface out is done with a couple passes through the thickness sander giving the surface shown in the bottom photo. Another benefit is since the sander references off the back side of the piece the sanded face is now parallel to the back.
Gluing the pieces together can now start. Here are pieces 1 and 2 which will form one face of the bowl’s turning blank. The two “C” clamps are used to make sure the pieces faces stay aligned and don’t slip when the orange clamp is tightened down. They get removed after a couple of minutes once the glue has a chance to grab. 
The same process is followed for the remaining two sets of glue-ups. Here all are clamped up ready to set overnight while the glue cures. I probably don’t have to wait that long but scheduled these steps to be done at the end of the day so they could cure overnight since the shop cools down this time of year at night.
In the top photo the glued-up blocks have had their edges trimmed flush and the faces run through the thickness sander to make sure that the faces are flat and parallel to each other. The blocks are arranged in the order they will get glued together. That’s shown in an edge on view in the bottom photo which shows how the thin layer is sandwiched between the thicker outer layers.
With the glue cured the clamps are removed and a rough circle ¼” larger than the finished piece is drawn on the top face. Also, a 1 1/8” mounting hole gets drilled, both of which are completed in the left photo. Next is to cut the round blank from the square block. In the right photo you can see how I use as push stick to keep my fingers from being in line with the direction the blade is cutting. A useless bit of information on the push stick. It’s the same one I have used on various machines for over 40 years and it does have a few chips and marks where it has done its job.
A couple minutes later the blank is cut and ready to mount on the lathe. The process for mounting and squaring the blank in the lathe is the same as the other blanks. Once that’s done, I turn the blank to a smooth slightly oversize cylinder. The pencil line on the end of the blank is close to the final diameter.
Once again because I am trying to make a matched set the bowls need to be turned identical to each other and that means another template. In the top photo the outer edge of the bowl shape has been cut out on the scroll saw and the waste bowl shaped is greyed out. It just needs a little finish sanding to fair the cut edge. Because I will need to flip the piece end for end during turning a tenon will be left on the bowl. That’s marked with the red arrow and will be cut next. The bottom photo is after the space for the tenon has been cut along with a set of reference dimensions (red ellipse) to be used to get the bowl close to shape.
With the template in hand, I can go back to the lathe and turn the blank to its final diameter. Once that’s done the template information is transferred to the blank. The circle on the end of the blank is the diameter of the tenon that will be used when the blank is reversed to hollow the bowl out.
Using a parting tool, steps are cut to the depth listed at each of the reference lines. The intersection of the step’s vertical and horizontal faces gives me the outside diameter of the bowl plus about 1/32” at that point. The red arrow points to a typical diameter. From here the excess material gets cut away in a rough arc. 
Here is after the first few passes knock off the corners and some work has been done to shape the blank into a rough curved surface. Once smoothed a bit more the template is used to find high or flat spots which are then marked for adjustment. One note, this is a subtractive process only. If a cut is made too deep then the whole bowl shape has to be shifted toward the 4-jaw chuck on the left and even this is limited so material removal is done judiciously.
This is the completed shape turned and sanded to a 90% finish. The tenon that is sticking out of the bowl’s bottom at the right is temporary. It will be used for the jaws to grip while the inside of the bowl is hollowed out and later removed. 
Next Up – Finishing the Bowl & Making the Lid
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