Michael,

> I confess to being a bit vague re the start n stop points, so it's probably user error again.

It can be important to be precise when you're constructing things, because you'll often want pieces to join up with one another. So be careful with just eyeballing things, it can cause problems later on if you're doing a more detailed construction.
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In the interest of getting the info out here and my own understanding,
I meant a bit vague in comprehension, rather than execution. As an ex-draftsman, accuracy is ingrained. lol
Intuitively I expect to tell it what to revolve (selection) how far to revolve (degrees in text input) and what axis to revolve on. I'm not clear on how the start and stop points are used to define that axis, especially for the cases it seems designed for, where that axis isnt perpendicular or parallel to the active view window. I'd guess its related to the way an angle is defined but haven't explored enough for the penny to drop. I've successfuly used them to revolve by drawing two points on an axis but what I've inputted by the random distance I chose between them is anybody's guess.

I'm painfully aware of breaking the injunction to keep one's mouth shut and risk appearing stupid, rather than openning it and thus remove all doubt. However, its a good cause and at the least all the experienced nurbists get a good chuckle.

Cheers
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