Dear Zbigniew, Thanks for all your comments and suggestions.
To correct myself on the A3, there wasn't much play in the valve gear, it was in the reverser and the linkage to the valve gear, more for my satisfaction than the expectation of better running, as it it runs very well now. I did assemble a C&S Mogul--the play in all parts of the valve gear was "overplayed".--It was sloppy! There was one fellow, whose name I can't recall, who solved the problem by manufacturing all new valve gear! Probably the only way to sure success! I appreciate your input and experience on assembly and testing. Steam on, Geoff. Dear Geoff, >Thank you for your kind words. As I elaborated on in another email >just sent, I am still hesitant about the gap. Measurements convince >me, although the extra amount of work and the need to shop for the >components may be a strong counter-argument. I haven't decided yet. >I have to remark that my efforts to keep every Joule of energy in >place should make me a perfect Dutchman;^)! But as to my origins, >they are more steam-and-narrow-gauge-land than under-water-land! >I am most intrigued by your work on removing the play in the valve >gear. I believe this is a long researched phenomenon in the C&S Mogul, >but I have recently been playing around with the valve gear wondering >if the play of about 1 mm should not be reduced... (the steam inlets >in the cylinders are about 1.5 mm!!) In effect symmetrical steam >transfer is only possible in one direction (say forward) while >the other direction will be strongly asymmetrical (only one side of the >cylinder will receive steam). Surprisingly, air test only shows >later activation of the movement in the asymmetrical direction, not >a much more violent and irregular (un-smooth) running. In fact, for >small openings of the reverser the running is very nervous and violent >in both directions (symmetrical and asymmetrical steam inlet opening) >to the same degree. This would mean that there is little practical >need for removing the play, it would only shorten the dead region >in the reverser range but not improve the running for small opening. >Happy steaming! >Zbigniew
