I have the top tipping wheel and I have a bottom small u groove, but I would have to make a flat one.
I only have one shot at this as I just have the bits of duct and no spare.
As it's a round tube, a tipping wheel won't help much, as the flange will need stretching on the outer and shrinking on the innner.
If it's a one off, I would make a slit in a 10mmx100 bolt or bar to the depth, the gradually pull it over, use the edge of a cross pein hammer to stretch the outer flange, on the inner crush the tucks that will form on something flat.
Tipping wheels are for panels as Burdekin is showing
!st pic shows the scrap test. Best one of all. Shows the "P" shape to the bend.
2nd pic shows the final job that fits standard duct to some old non standard stuff. This bit will slide in the old.
A taft turned in spot welded to a taft turned out that overlaps it.
The turned in did ripple a little but dressed flat ok ish. tipping outwards was no bother.
I had a flat hardened anvil but not the same fitment as my Jenny, but a spin on the lathe later and I had an adaptor ring.
VERY pleased with the results on some 1mm galv sheet as shown in the photo. The U grooved anvil that I used Friday
is sitting in the background on the backstop bar.
Just goes to show your never too old to learn, and thanks again for the advice.