These two walnut bowls are very much alike in all aspects of their design except for the shape of the upper surface. I split both blanks from the same log. After hewing and planing both bottom surfaces flat, I gave the one an arched top and the other a flat top.
Above are both blanks. It may be more intuitive to create an arched blank when working in the “bark-up” orientation, since the arch is already there the natural form. But it can also be done with a “bark-down” (or “pith-up”?) blank, and may be a good choice for certain logs and circumstances.
Realizing that the growth rings were difficult to see on the blanks and having just discovered the feature that lets me mark on photos, I’ve indicated the growth ring pattern with the yellow lines.
Both bowls were laid out in the same way on the upper surface, in a “rectoval” shape. From the angle above, you can see the same sort of grain pattern on the inside of the hollows.
Drop down a bit and the difference made by the blank form becomes more apparent. Neither is inherently better; it’s a matter of taste, setting, and/or purpose. It’s good to have both options to be able to make the best use of a particular log.
I chose to finish the interior of both bowls with a subtle texture by paring the surface with a relatively shallow gouge. In the case of this bowl, I’m using a Hans Karlsson bent gouge 150 sweep (the edge represents an arc of a circle 150mm in diameter) 45mm wide, equivalent to a #4 sweep or so, I’d say. The specific gouge doesn’t matter, but sharp does, especially when pushing an edge that wide through dry (at this stage) walnut. Even with all that pushing, two holdfasts and some rubber pads are all that’s needed. Simple and effective. I don’t know what I’d do without holdfasts.
The side panels of both bowls were finished at the bowl horse with a drawknife. I carved flutes on the end panels but I varied the number. Flat top got 12 flutes, and arch top got 9, slightly wider.
There’s a knot in the end wall of flat top. It carved easily, and I like the way the grain swirls around it.
I carved the same nail-cut pattern on both bowls.