She is welding the rear head casing to the tube. Or do you mean the rivetting bit? Those are the barrel nut insert rivets. Both the tube and threaded insert are tinned. Rivets inserted and dollied over and then the whole lot is heated so that a soldered joint between the two is formed to reinforce the rivets.
Last edited by Peter Laidler; 05-29-2016 at 03:01 PM.
The film was taken at BSA and the Ordnance man was a local Home Guard who acted as the escort to take the guns the short distance to Weedon. The short story of the making of this film and the original of it including the names of the people shown is housed at the Birmingham City museum of industry and technology
Interestingly, the production notes refer to the rivets as 'drive rivets' which have a coarse threaded shaft - almost like a very coarse pitch self tapping screw - which half-turn thread themselves into the hole. In practice this seems to be a myth because they're just flat-head rivets punched in! The drive rivets were definately used to secure the front and rear barrel supports in the Mk3 guns which were also secured with soft solder.
The arc welding part where she arcs the front left and right tabs of the trigger mech housing (or the trigger case.....) to the tube was done in two hits. One side was left to cool right down before the next side was done. This was done this way by arc welding so that the instant heat didn't distort the casing (well it did I suppose, but to a very small degree). Then the next side later and distortion was minimal. The rear head casing could be gas welded because it was equal heat radially around the complete rear end of the tube.
One of the women welders in the film was named in the Sten book
Last edited by Peter Laidler; 05-30-2016 at 05:54 AM.
In the days when noone noted serial numbers. Presumably they were test fired before issue in the Ornance chain?
'Tonight my men and I have been through hell and back again, but the look on your faces when we let you out of the hall - we'd do it all again tomorrow.' Major Chris Keeble's words to Goose Green villagers on 29th May 1982 - 2 PARA