One of the tasks that tends to be problematic is the OD finishing of tube material. From hand finishing to placing tubes in a lathe there are all manner of ways people try to work with tubes. In reality there is a much more simple and fast way to do it that it seems many are not aware of. There is the centerless style of machine most have seen where the tube spins while being processed. Many are not fans of these due to the risks of the spinning tube. If there is a bend to the material the tube can flail around and get out of control. They also tend to be aggressive in a general sense as far as material removal. If you have nasty rust covered material with severe pits they would be the best option.
Planetary tube grinding machines do not spin the tubes during the process, which creates a safe operator environment and eliminates the possibility of barber poling.