while certaily a neophyte as far as live steam
this is what i think i have learned so far-and i could be very wrong-but so far it works for me
i have had great success with performance at low speeds -all things considered -ie load and flat track, outside temp-
by simply adjusting the fire-i run about 65%-80% of full open, and also , at least on the frant s, i am judicious about the water bath for added pressure-i get longer runs by far
on my #24 SRRL R/C roundhouse, which i can sorta get to crawl if Im simply not too hamfisted with the joy stick,
i simply never wait until blow off, and once heated -which in turn comes into the cab and heats the old style roof/ceiling mounted tank, increasing gas pressure , i back off the gas valve just a bit-which on my engine lowers the jet engine whine of the air intake/jet adjustment a bit
and it really helps-not only with throttle adjustment control
but also with an efficient use of water and thermal efficiency of fuel in heating the boiler
-i understand that a gentle heat up is actually better than a full blast, as the loco itself also must absorb the heat and when this is lower it is more efficient as more of the usable heat is taken rather than going up the stack -
-ie you dont get as much waste, blow off, etc
you have to find the equilibrium between load, grade and firebox rate
its sort of a trial and error process to learn but i am often able to run really slowly, like scale 5-8 mph
