If you insist on being AR about it, here goes. On a stationary flange which has a bushing for the pin, the pin rotates in the bushing because the pin is bound in the birdseye. Upright hammer butts, grand wippens to name a few. On a stationary flange which has the birdseye, the bushed assembly rotates on the pin. Grand hammer shanks It depends on the assembly execution as to which part is secured to a rail and which is free to rotate. So in some instances the pin rotates in the bushing and with others the bushing rotates on the pin. In either case, the pin is restrained either by a clamping plate or a pressure fit. In and of itself, the pin does not rotate but as a member of an assembly. Its function acts according to its relative execution within that assembly. Put another way, The pin does not rotate when it is part of the assembly which is secured to a rail and is stationary. In this instance the mating assembly rotates around the fixed pin. The pin rotates when it is within the assembly which is not secured to a rail. In this instance, the bushing is stationary and the pin (restrained by its assembly mount) rotates in the fixed bushing. It depends on which side of the hinged assembly you hold secure. When cutting a branch off a tree it does matter on which side of the saw you are seated? -- Regards, Jon Page
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