Very nice idea, and I am copying it, sort of, for my Kubota Excavator. I have all the major parts, and will build before I start a demolition job next month. Thanks for sharing the build. I'll document mine when I get started.
How did you size the solinoid valve on the hydraulic cylinder?
I have a kubota 3710 with a woods 9000 that runs off a woods pto pump which is rated @ 3.8 cubic inches. The manual says it requires 8-10 gpm @ 2400 psi. I guess about the same as yours.
The excavator isn't so bad because it moves easier. Maybe down the road I'll have to replace the footvalve on the excavator from hammer stuff to thumb stuff.