Making Masts?

I was talking to a friend about possibly renting a power plane for
mast building and he offered the use of a 6" tilting bed
planer-joiner. Venerable old machine with lots of cast iron and a
huge
motor. I a not sure how long the bed is, I just had a quick look at
it. Maybe 2 feet or so. Is there any practical way to use that to
help
round out a mast from four sided stock?

Le