Walschaerts Valve Gear w/o Combination Lever?

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New Member
Hey everyone!

I've finally finished the geometry and calculations for my G Scale 4-6-0 Live steamer project. Tricky getting things to work together and still be able to be manufacturable by myself.

I designed a Walschaerts valve gear, but didn't put in a combination lever. With almost no valve lap I have about 90% of each piston's travel getting power...
I'm also putting in a very hefty slomo system; I'm taking apart an RC servo which has an insanely low gear ratio from the little tiny 5V motor to the output shaft, i'll run the axles to the output shaft of the servo, and swing a weight on where the motor should be. I'm hoping to be able to run on a test stand at incredibly slow speeds.

THE QUESTION: do you think there would be that much of a noticeable difference in performance at this scale if I took the few hours to add in a combination lever?

Thanks in Advance for any input!


Its rare to see true Walschearts in G scale that can be notched up(the real reason for lap/lead and the combination lever that induces that). A few high end Aster gauge one models have it. But look at the Roundhouse models, they have the combination lever, but its just for looks to make the gear look more"complete" vs without it. The lever imparts no lap or lead to the motion. And please do post up some pics. Mike

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