Tom Gardner wrote:

I'm designing a new generation machine that will need to push a 5/8" rod
two inches with about 600 lbs of pressure. It also needs to be a bit
"springy". The new machine is only about 5 cubic feet in volume and
will replace current machines that are 4' x 5' x 6' in volume. The old
machines use hydraulic power for the pin push. I want the entire
machine to use 120VAC only. One option is a small pump and an air
cylinder, another is a linear actuator with an in-line die spring or
something I haven't thought of. The rest of the machine is most of the
way there and rather clever...for me, anyway. What pitfalls can I
expect with a linear actuator?

Not sure what the control / timing requirements are. Would this be
something best done with a continuously running motor, an electric
clutch and a gear drive to a cam type setup?