+1 on soldering the hinges. Matter of a fact, instead of trying to solder the tubes on the steel lower trunnion body, I machined and fitted a hinge block insert into the steel body.
I also used soft solder but fitted all the joints with blind 1/8\" pins for reinforcment. For example the \"key\" on the bottom of the trunnion cover has 2 hardened dowels in the solder joint.
Works for me, your mileage may vary.
nitewatchman
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