The design in ME 4639 by Don Thorpe displays excellent lateral thinking, but he will not be surprised that something similar has been done in the past. The Great Central Railway (possibly Robinson?) had a device called an Intensifore which had the double piston arrangement, but I don't think it had the return spring, the whole reservoir was pressurised.
Anyway, this concept is for sure going on my next engine, but with 2 needle valves and 2 sight feeds as on both my existing locos I'm not convinced that the oil fed to a central position goes equally to the cylinders
Edited By duncan webster on 26/05/2020 13:54:15