Looking for suggestions for a durable wing stay design. My current ones start of as round tube which butt welds onto flat bar which is then bent over the wheel to form the shape under the cycle wing. There is a clear weak point at the point where the flat bar and round tube butt weld together - end on end.
Any suggestions ?
One has failed and I am going to repair it by replacing the flat bar with a longer piece which I will run down the side of the round tube and give a much longer contact area between the two.
Really I'm looking for suggestions for a design which has no obvious failure points built in as my current ones, frankly, do.

[Edited on 3/6/04 by zilspeed]

If you use a tube that you squeze to make it flat neare the tyre.
I think this will be stronger

I would flatten the ends of the round tubes and insert the flat bars inside them, then weld the two together. There will still be a weak point at the change of section but the flat bar will better supported and I think will look better than running the bar outside the tubes.
Just my opinion though.

Mick

[Edited on 3/6/04 by Mix]

Perhaps a web welded on the inside would help 8mm bar.
These cycle wings have and will always give trouble to the masses. The other thing is to get some fake carbon ones made of plastic from that lighting supplier.
Fibreglass ones are heavy unsprung weight. Reduce this and the brackets will not have to work as hard.......

Im with Mangogrove, flat bar but welded with webs spreading the load at the joint between the flat bar/tube. What u using to weld Mig?
Shug.

Mig is all I can do shug.
As someone said to me years ago, "I'm an armature ".
I believe he was an electrician.
I sincerely hope the weather improves or I'll be doing nothing today.

I believe the MK ones are done in the way of...

quote:

---

Originally posted by Mix
I would flatten the ends of the round tubes and insert the flat bars inside them, then weld the two together. There will still be a weak point at the change of section but the flat bar will better supported and I think will look better than running the bar outside the tubes.

---

Hi,
I'll be doing my wing stays soon and perhaps I'm being naive but if the edges of the bar and flat are bevelled to permit full weld penetration (multi pass if required) then shouldn't it be strong enough no matter whether it is a simple butt weld? If not then I'd suggest cutting a slot in the round bar to allow the flat bar to be inserted for 25mm or so before fully welding.

Cheers,
Craig.

Flat bar up the middle of the tube it is then lads.
Sometimes all it takes is a couple of ideas to help see a better solution

I had the same problem

in the end I welded them back together, added a small bit of metal around the area where it snapped and added a metal strip joining the two which makes it more rigid

mark
Rescued attachment cycle.JPG

I used tube for the whole shebang as follows:

cut a steel plate which has holes to match those on the upright intended to locate the disc covers.

bolt in position using either a spacer if fixed or if you have a mishmash of wheels then go for double nuts.

use a pipe bender to form 90 degree bends in two peices of pipe. one for the front stay, one for the rear.

assemble on sheet with clamps and weld to plate as desired.

trim plate back and tidy up.

when fitting arches bed them down on either a mastic or light filler.

Having had an immediate failure with the original design this has given me 1000,s of miles of happy use. i even managed to damage an arch keeping the stay intact...

Squeeze the tube -- while red hot then reheat and quench to refine the grain structure
Also don't weld the joint braze it