This is a new try at a scalloped bowl
This reminds me of my first attempt with making a segmented bowl where pieces seem to go effortlessly together to create a perfect ring! Stacking the rings and aligning them was the next problem to solve (more jigs).
To make your bowl like this, of course, you first have to sort out the joints.
The problem: if you had started with a piece of accurately planned all round timber, do you have a way to accurately cut six trapezoidal triangles that fit together perfectly like your petals (no)?
The solution: to make a "Jerry Bennett" type jig for cutting segments and then devise a way to use it, whilst also holding your six petals, so as to make perfectly (effortless) accurate cuts.
It makes sense to master the cutting technique with flat timber before going to the trouble of shaping it e.g. creating a hoop that's later cut into perfect triangles.
If you take accurately planned all round timber and add a bevel to one of the long sides, this can be used like the "reference" top edge of your petals, to perfect the technique.
Providing you can perfect the cuts to construct six bevelled triangles that fit together perfectly, using this "reference' top edge, then you will also have a method to cut and assemble your petals.
NB I found that the best way to make segments that fit together into a solid ring was to cut the first edge and then deliberately cut more off than necessary on the second cut. Although this makes a smaller diameter ring, you are much more likely to have the segments come together to a perfect point. When cutting segments, a trapezoidal triangle is created when the angle of the table saw is deliberately moved away from 90 degrees. The same thing can be used to cut the two angled edges of each petal. Have you considered making the petals from contrasting dark and light woods e.g. joint two pieces of wood before creating the "donor" hoop and later mixing them up?
