Sweet find... but this is more or less say 'common knowledge' I've always been reluctant to apply. Maybe because I'm lazy or don't really believe in links soldered to washers...
I'm still trying to find a way of attaching some U-swivels to metal hollow shafts... and people keep telling me to 'cork' them w/ pieces of wood.
But I don't wanna...

There's got to be a way...
Peace!