I don't think anything could be worse :)

Thanks
Yan

I was just looking at the failure picture above and it seems there is very little if any penetration in the weld. To me, it looks like the bead of molten aluminium acted as a glue rather than a structural weld...

That was the problem. The factories hired people with no welding experience and sold the bikes without testing the frames first. Being a welder there was no or little welding penetration of the metal parts. Roger

@rhenning
 

A bad welder can kill you (basically).

I fully agree with you.

When I obtained my certification as a car mechanic, welding was part of the comprehensive examination AND if one failed the welding test one failed ALL TESTS!

So, not everyone has a desire to fail like tern!

But anyway, I hear you, loud and clear.

When dahon changed their dealer system in Europe, the European distributors that got pushed out were selling off their stock of naked dahon frames, but that was many years ago. You could ask some current dealers if they're willing to sell you frames.