Got Vederstein's Swashplate Engine finished. When I first finished the parts and assembled it (unpainted), it ran. Then I paint all the parts, reassemble it and no go??? Then figured it out. The paint on the underside of the swashplate was still rather soft and balled up and the steel balls on the top of the pistons couldn't smoothly move it. Sanded off the paint and then had metal on metal and you can see the results.
Grasshopper
https://www.youtube.com/shorts/9EHFBN10MWM
Grasshopper
https://www.youtube.com/shorts/9EHFBN10MWM