Originally Posted by
tosh
Never heard of that! What do you mean by work harden?
It's just mean as the material is worked it will become harder and more brittles. in a fuel pipe the variation will harden it over time and eventually it will crack and leak.
Don't get me wrong. I don't think copper will crack and break up really quickly but I did not want to be doing this again so just done everything to make it a one time job