clip on and spin design

[Rossi]

Hi all,

I wonder if somebody could help with design, I've made a precision screwdriver with a spinning cap. But the spinning part is the issue.
After making 3d model in plastic I’ve understood that such design probably will not work when done in metal on lathe.
The idea was that cap has a lip that has to go over the pump (see links) that way allowing a cap to spin, but not sure if lathe can make such a cut and also not sure if made in metal it will go over the bump as metal is a lot harder material and has not have a “give\expand” like plastic do to get over a bump.

https://drive.google.com/open?id=1KeVIG ... SSlIk9ERs9
https://drive.google.com/open?id=1PfNpq ... eeiz1BA_cn

[NittyNight]

Instead of incorporating the 'Bump' into the design, replace it with another 'groove' . When it is time to 'Snap' the metal parts together, fit a 'Short' round-wire 'Circlip' to one or the other parts to create the 'Bump'. The circlip will 'Give' and have enough 'Hold' for the job. P.S. What I mean by 'Short-wire-Circlip' is a round profile, 'Cut' circle of springy wire that has enough gap between it's ends that it disappears into the groove when being inserted but 'HALF' reappears when it lines up with its mating groove.