I have machined the Cylinders for my Allen Mogul. The Castings I have were cast with integral Steam Passages from the Valve Ports to the Cylinder Ends. The Cylinders are machined symmetrically and the Distances from the Ends of the Cylinders to the cast Edges of the Passages are all in the order of .34" . If I were to clean up these as-cast, razor-thin edges I would get say 3/8" for the Distances. The Concern I have is - at the Dead Centers the Distance from the End of the Cylinder to the Edge of the Piston Ring is 7/16", i.e. there is only 1/16" between the Edge of the Piston Ring and the Passageway. The Piston is fitted with qty 2 Piston rings, supplied by Allen Models. The Distance between the Piston Rings on the Piston is 1/8". Do I dare put the Piston Rings in a single Groove in the Piston ?
By the way, these are Cast Iron Cylinders.
