How does the regulator and superheater work in this stripped down 3.5" GWR boiler? Particularly the round item with the pcd holes?
I was trying to work out if i could utilise the superheaters to get compressed air to the cylinders instead of having to make up a little manifold, but realised i was faced with this round thing with a hole on each side and the small holes drilled around.
thanks for any help