Its the oxide. If it was not for that coating the metal would simply go up
in a flash and a bang, trouble is its horrendously hard to make stuff stick
as the oxide simply comes away. I seem to recall some kind of etching
adhesive could glue it, but the best fix though it will look bad is
mechanically bolting plates onto the joint I think.
Brian

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This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"pinnerite" wrote in message
news:20210402171053.d019320f5e4e16594ebc2e2a@gmail .com...
Let's be fair, it may not be the glue. It could be the user - me.

he items glued together are the ends of the arm of a cast alluminium patio
chair. One of six. The arm is bolted at the bottom to the seat and at the
top to the chairback.

The break came at the point where a bolt is screwed through the arm and
into the chairback. It simply snapped.

This first happend in the summer. When I first tried to locate the
sections, I realised that the joint had been under stress. So after gluing
wit superglue, I filed the hole to allow the bolt free movemnt.

I thought that would be the end of it but a couple of days ago, the first
when we coud sit with up to six people, it snapped again at the same
point. I forgot that I had used SuperglueIt and because it looked clean
glued it agin wuth two-part gorilla glue (a bit like Araldite). It was no
good and came apatrt again as I bolted it in.

On inspection it hada sticky feel and instead of glinting, the brocken
areas are a dull grey. I tried cleaning them with petrol. I am not sure if
I was successful.
So before another attempt, I thought I had better garner the benefit of
experience.

TIA, Alan

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