Peter Epperson posted this to the ferro-cement list.

My friend found this roller at the dump many years ago. He didn't know what it was but knew it was good for something. Indeed it was. We have often joked that without it we would have to go out of business. We use it for rolling the rebars that define the shape of our tanks. We use a #4 rebar at the top of the wall of our tanks and one at the bottom. These are primarilly for giving the tank shape and rigidity before we shoot the mud. The roller has shaped miles of rebar and has been repaired and improved many times. Basically it is very simple and plugs in to the 2" tow receiver of a pickup truck. This is the ticket.