[MrFixr55]

I'm gonna hazard a guess here. the ball was likely glued or soldered to the shaft.

The pin that looks like a nail goes into the spring. The spring goes into the "outer" brass shaft.

Put the inner shaft into the outer shaft and hold the 3 balls in place Push the inner shaft into the outer shaft only to the point where the balls seat the farthest into their holes. Insert the assembly into the steel "collar. When you let go of the shaft, the spring will push the shaft out, so the 3 balls contact the ball soldered in place, keeping the shaft in place. The ball bearings act as a planetary gearset.