I am a tool user with opposable thumbs... and tools

By now, I should know better than to say, "I can't..."

A solution to the question of how to machine the ends of thin-walled tubing without having either a steady rest or a six-jawed chuck has been presented, nearly simultaneously, by two different friends.

Plugs.

A plug shall be machined to support the tubing (internally) in the chuck at the headstock end.

The tailstock end will be supported by a second plug, riding on an arbor which extends through both plugs and is supported on a center in the tailstock. The tail end plug will be recessed in about an inch or two from the end so I can sneak in a boring bar to turn the ID at one end. I don't need a turned ID on the other end, I'll only have to do that once.

I'll probably fashion the plugs from aluminum.

What keeps the arbor from moving toward or into the spindle, I don't know yet. Perhaps a few set screws. Something tells me I might have to try to be clever. I'll figure something out. No, I don't have a dog plate and center for the spindle.

I'm just embarrassed I didn't think of this answer on my own. Of course, it would be nice to have more and better accessories for the lathe so I don't have to keep making custom tooling to hold my parts...