Been watching this thread with interest..Aster has built several compound
locos,,Swiss A3/5 and DR 0+8+0 ++0+8+0 and J.V.R. did a lot of the Design
calcs etc for them ,he wrote a very good article in G1MRA Journal on
compouding in our small size about 2 years ago.Basics seem to be ahigh
enough pressure from the boiler so that aftre the first stage cylinders
theres sufficient left to do useful work in the low pressure side, the ratio
of cylinder sizes comes out different to full size locos from memory on the
DR loco it was 10mm bore [high] and 13mm [low]
this loco is very strong once its warmed through and runs like the wind! and
no reheating was fitted..
Gordon Watson.
