After reading the "how do they make steel wool" thread above has got me wondering..
How do they make copper "solder ring" fittings?
I can see that the actual copper part could be bashed out by a big machine but how do they get the solder into the groove on either end?
You could sit there for days trying to get the solder into the groove with a blowlamp/soldering iron and never achieve it.
The joints don't appear to have any discolouring due to heat.
So..how do they do it?
sponix