Tack welds on ball joints!?

[Webbaldo]

Been cleaning my torsion arms up ready for a mate to swap balljoints over.

Anyway discovered three of the four arms have tack welds on the top of the ball joint.

Any idea why? Cant imagine if they were loose such tiny welds would hold them on?

Confused

 

[Webbaldo]

Found this off another type of car forum, maybe it's the same?, US thing it seems

Tack welding ball joints was once common practice

They often don't fit quite so tightly the second time around, and if left alone, the infinitesimal movement that can occur with thousands or millions of tiny impacts can enlarge the holes, and cause meaningful looseness.
A little tack weld can prevent that initial unmeasurable movement, and prevent the joint from loosening later.

Also, in a world in which few cars went beyond 100,000 miles, and most ball joints lasted more than 60,000 miles, nobody ever worried about how they would get that second set of ball joints off forty years in the future.

- Eric