I know of ways to do the fluting through laying out the spirals with lengths of tape or paper etc. or using the indexing set up on some/most lathes. I am just having trouble in mentally figuring out how to do the turning part of these versus havint to basically carve the whole thing and sand a whole bunch. My brain really doesn't like thinking in 3D and turning the objects at the same time. He also has another one that has a varying width ridge that runs diagonally across the surface of the piece. Still have no idea on that one without basically carving away the entire surface.... I will try to get a picture to explain it better though.
Come on Sonny, you've been doing this long enough to know by now that all the bowls we turn won't hold water. I know I've made my share of bowls that turned into lampshades when I went though the bottom. Admit it, come on, it will make you feel better. :)
I have not been smoking anything funny, needer.
I had a router crafter from Sears in the seventies that would do some cool stuff. But I don't think it would do the complexity of these.
I do belive you are seeing a spiral attachments work here.
The turner (if you could call him that) just used it to put a new twist on things. :)