Howdy Folks,
I bought a wrecked Town and Country tandem a few years ago that had a severely verticalized front end, so I cut it off and replaced it. An interesting thing was the 4130 chrome moly tubing was internally reinforced with approximately 1' long sections of tubings fitted inside the frame tubing at all the joints. This particular Town and Country was from about 1959. It helped explain the extra weight of the frame. They had a beefy and heavy 1 1/8" fork with a reduced and machined section for clamping the steerer to the stem in addition the the stem wedge bolt. Also, Schwinn used lead solder to clean up and finish their brazed joints on these frames. I suspect this is also the case on the the Schwinn Continentals made in the 40's and the schwinn worlds from the same era. Paramounts are brass brazed and don't have this problem. I'm not sure about the Sierra or Super Sport models Schwinn made with 4130 tubing as upscale bikes during the late 60's and early 70's. I never saw one stripped of paint. My early 70's Paramount tandem has the rear curved seat tube and is fillet brazed.
Paul Brown
Santa Rosa, CA