Spherical Ball Joint question...

[Ewen]

...how is a spherical ball / Rose joint made ? I've one here on my desk, not the split type, how do they get the inner ring inside the outer ?

[Ewen]

..

[kjgreen3]

I think its a combination of heat and cold, the tolerances are tight but the inner ball is supercooled probably in a vat of liquid nitrogen whilst the outer ring is heated up. You then quickly put the inner (slightly contracted ball) into the outer ring (slightly expanded) and viola one completed ball joint.

 

I remember this from physics experiment with a ball and ring although dissimilar metals so the expension contraction was more exaggerated. the ball wouldn't go through the ring unless the ring was heated up first by a bunsen burner.