In article . com,
" says...
Hi

I have a strut on a pram that has sheared. It's at a 'springy' point
but isn't particularly load bearing. The fracture hasn't caused any
distortion to the tube, and the two halves still mate nicely.

Main problem is that the fracture is just at the end of a curved
section, so making a suitable plug to tap into each end won't work.

The tube is aluminium (or an alloy), so 'simple' welding doesn't seem
to be an option for repairing it. The tube is also one of several
welded into a reasonably complex array, and so isn't easily detachable
for popping some type of replacement in.

I have thought of two ways of repairing it:

1) Cut the tube off at a lower straigh point, make up a replacement
section and join to the original: a) with suitable plug/dowel; b) by
welding old to new. From these two I'd prefer 1a as I can just about
do all of that myself.

2) Align and secure the two parts, then fill with some suitable epoxy
or meltable resin. Once set the resin would need to have the strength
and durability under flexing to keep the joint stable.

How about this:
Take a piece of aluminium mesh (the sort you use with car body filler
for bridging holes) and roll it up so it's a snug fit inside the tube
and several layers thick. Jam one end of the rolled mesh into the
curved tube section so it takes the right shape (ish), then remove
it. Now lag the inside of the curved tube and the curved half of the
mesh with epoxy and jam it back together. Try to get plenty of epoxy
through the mesh so it bonds all the layers. Then glue the straight
piece of tube and the other end of the mesh. Although the ultimate
strength of the repair won't be great it should be adequate, and will
hopefully reduce flexing and the chance of a further fatigue failure.