I learned a lot from this loco, specifically that it was possible to reverse the pistons by reversing pressure. I swapped out your controller for that with one that I think correctly implements your intention, and I'm very happy with it. Now the "coolant loop" between the firebox and boiler is really tricky. No pumps are required, but a control valve absolutely is. For this version I used the equation " clamp(-10*x-90, 0,1) " in a function block to read the boiler pressure and regulate the "coolant" loop. I have a second controller that tries to regulate the fire to match what is actually being taken out of it by the coolant but haven't published that.

I saw your train in this video. https://youtu.be/-E0IiAmQHcE

mine now

It bypasses brake input from other R-BUS compatible car. so you can double heading with brake coupled.

So what does the Double HEading Button dO?

ok thanks for the help!

i will try

https://www.yosemite.com/what-to-do/yosemite-mountain-sugar-pine-railroad/

from which railroad?

can you make shay No. 10?

Add some load to pistons (use higher gear ratio, or add flywheel) can make the stop-and-go a bit less noticeable. also the piston works better at lower steam amount. try regulate it below 1 with variable valve, but the value differs on your amount of load.

very nice shay and how did you get the pistons to work cause for me they keep stopping and going as i was also doing a shay?

All I think of is a Heisler or maybe a Climax.

amazing creation

nice use for pistons!