Cycling UK Forum

A mate was here last evening and as normal regaling me with what he'd found on the main Facebook cycle sales forum.. here it is the guy who found it wanted to know the maker was , it was Italian he thought and had been attached to a plain 700 slightly rusted steel rim. one side is fixed, see 2 different threads and other for gear sprocket... this side.. anyone, Brucey?? cheers w.

More interestingly, the spokes will be headless, just a piece of wire with a circle in the middle and threaded at each end.
Must be fun on a spoke length calculator!

Looking at the flanges, they are riveted to the barrel/middle bit, looks like 6 rivets per flange.
Are the flanges cast, forged or stamped out (stamp the round holes and roll/burr over to make the spoke holding circles)? The curved edges of the holes in the flange at the back of the picture suggest to me stamping and rolling/burring over.

I have seen that before; the idea is that you don't have J-bends in the spokes to break.I forget what they are called. It wasn't a bad idea, but it never really caught on.

Instead of the “problem” of the j bend, don’t you now have a “problem bend” where the spokes go from straight to curving round the pulley thing?
As well as a new set of things to learn about lacing up… presumably both ends of a (double) spoke are the same, ie both ends pulling spokes or both ends pushing spokes? Otherwise you would get the spoke migrating backwards and forwards round the pulley in response to different loadings at the 2ends of a double spoke?…and flexing the straight to circular bend?
Straight pull spoke’s presumably require a more complex process to fabricate the flange, eg. forging?

I count 10 pulleys per side, making it a 40 spoke wheel… the old standard…with fully tangential spokes, as in traditional 40spoke 4 cross wheels

I do like a nice, clear photo ;- )

did he get his pension credit sorted?

Made by Constrictor, best known for their rims. They made a range of parts, both pre and post war.

Ugly wrote: ↑23 Nov 2023, 6:32pm Made by Constrictor, best known for their rims. They made a range of parts, both pre and post war.

I followed the above to the Classic Lightweight site where there is a description with illustrations, here towards the foot of the article :-
Constrictor 'Circum'
https://www.classiclightweights.co.uk/c ... ubs-1950s/

in theory it should be possible to make the hub flanges a bit lighter, because they see less stress. In practice,I can't easily see how.

A similar approach was used in the no-longer-available MIT Copenhagen wheel https://senseable.mit.edu/copenhagenwheel/wheel.html. In that case, the hub was made of plastic, and the double-ended spokes looped around U-shaped grooves on the hub, which presumably spread the load. I think it was more the weatherproofing, or rather the relative lack of it, that led to its demise, rather than the novel means of anchoring the spokes.

if the wheel sees service loads which cause one side of a double spoke to become slack, then it becomes important that the spoke is well-anchored to the hub. In the case of the constrictor design, I think this is the case, but with the Danish design I'm not so sure.