Karl wondered:
How do
you use conduit for tomato plants? Specifially, how do you tie to
thi
s slick
stuff?

This looks like an opportunity to build a tool!

Create a roller rig that will "neck" that EMT every few inches. Sort of
like a pipe cutter, but with a dull edge, so it doesn't cut the pipe,
just roll-forms a compressed line in it.

You might get away with just grinding a pipe-cutter's wheel to a round
profile. In which case, since all good Rigid-brand pipe cutters have
replaceable cutters, that's not a very expensive proposition.

Then... you set up your lathe without the tailstock so you can chuck up
the pieces, and just "step" down the pipe with the forming tool.

Heck! You might not even destroy the galvanizing, if you polish the
wheel.

LLoyd