^^My guess would be a subtle combination of 2 and 4? He slightly heats the tube and slightly cools the post, then uses something pneumatic or hydraulic to steadily apply pressure to the underside of the post with some sort of clamping device.
I've been thinking this over on the train, feeling a little
^^My guess would be a subtle combination of 2 and 4? He slightly heats the tube and slightly cools the post, then uses something pneumatic or hydraulic to steadily apply pressure to the underside of the post with some sort of clamping device.
I've been thinking this over on the train, feeling a little