Just a thought, you may be able to age the gun [ish?] by the threads on the screws if they are metric then I would guess post 1965? if they are BSW / BSF or some obscure size then I would guess earlier. kind regards Al.
PS. but I do know that old stock of imperial fasteners was 'used up' for many years after metric was adopted?
PPS. Have looked on Garvin's excellent site & I now think it has been soft solder together & what about those square nut's ! so now I think mid 1920's early 1930's?
Last edited by cringe; 23-01-2021 at 12:28 PM.
The 'Ripple effect ' those joint have would not normally appear on a soft soldered joint unless it did not get hot enough to flow correctly?
Soft ( Lead based) solder will scratch easily with a pin or needle. Hard (silver) solder or braze will not
Not done with a knurl driven resistance seam welder then ?