Apologies for the necrothread, stuck at home on strong painkillers and antibiotics with an abscess, reading back through what I've overlooked of A4A this last wee while.
Anyway, these look absolutely awesome, both the hand held and the telescopic. Think I'd have a go at making a nice elegant shaft for the hand held version like the one in the link above and maybe change the angle on the blade slightly to about 23deg, to give more of a natural stroke:
https://www.burford.co.uk/garden-and-outdoor/garden-tools/nunki-beech-handled-copper-hoop-weeder/
The telescopic one looks really good too. Could probably do something with a brush pole. I wonder how these do at making clay into a finer crumb?
Great idea on the hacksaw blade Ancells, I happen to have an old one lying about, I'm loathe to throw out good tool steel. I smell a project on the horizon so maybe I'm feeling a bit better after all!!