Double thickness of tinplate formed by folding along it's length shaped round a former and soldered in place. Epoxy if on alloy .If you want lugs just fold and pinch in a vice or pliers.Drill holes as required for stays. Or just solder on.👍 Takes patience but very effective.

Thanks Gary no I don't have access to a lath but will look at aluminium tubing as a fix.
Rick

Hi Rick, photo as promised and a rough idea of my solution for the chimney problem, I think this needs a bit more work as yet? Question, do you have access to a lathe? Regards Gary.

Hi Rick I favour aluminium tubing as you can buy any diameter you want, a 12" length is not expensive, then using milliput putty mould a few rings of putty around it say top, bottom and an inch from the top, square them up on a lathe then you can fix the four stays into the putty, which looks just like the real thing in miniature. Regards, Gary. (I'll bung you a photo.)

Thank you Hammer I like the bear can didn't even think in that direction great idea.
Rick

Depends on the size. I have used copper plumbing pipe. 22 & 28mm. Or beer cans cut off top & bottom slit down the length, bend around a former, solder joint. I have used all these methods.