[Antennas] Rusted and frozen steel pipe in aluminum tower topsection.

[Tom Bates]

>>Anyone have any experience with how to remove the rusted pipe without
damaging the softer aluminum collar?

This may work.  I've done this many times to remove "galled" bearings from
housings...

Cut the steel pipe close to the collar, and with an electric arc welder, weld a few
beads around the INSIDE of the pipe.  The weld will "pull" the pipe in, and hopefully
it will drop out before the steel expands. However, since steel and aluminum have
different rates and coefficients of expansion, the weld heat may also cause the
heated and expanded steel to "stretch" the aluminum and once cool. the pipe may
loosen in the fit.

No warranty expressed or implied.  Good Luck...

Tom   AA1NZ