Questions about the forging of a pugio and a balteus

[Crispvs]

That sheath was found in the remains of a rubbish heap and the suspension ring is almost certainly a hasty repair to replace a lost suspension ring which had originally been fitted, almost certainly of type 'B', examples of which have been found at Vindonissa.
I believe that the frogs have been associated with the sheath for display purposes, as is common in the cabinets at that particular museum, where separately found objects are associated with one another in the displays to make better sense of them to the viewer. I can think of a number of other examples, including a sqword blade whose tang has had disparate handle elements fitted over it to give a better understanding of what each piece is.

Tarbicus,

I do not believe it would be practical for very long to try to open and close the ring around the frog, as the metal would become more stressed every time it was opened and closed and would eventually snap. To that must be added the fact that where complete suspension rings of either type are found still attached to sheaths, they are always closed (and in some cased cast closed) and are clearly not intended to be opened (which would effectively count as breakage).

Crispvs