I know this forum is more about timelapse, but I am thinking the members here are experts in dc motors.

I am building a zero friction slider using skateboard bearings and stainless steel round tracks. I am going to test adding a pulley and weight system to it for gravity fed slow movement.

I also wanted to begin to learn the following:

1. For a move that in realtime would be a nice consistent slow slider move, what RPM motor would I need? No timelapse.
2. Is this a small "hobby" dc motor? Do I need gears or pulleys?
3. Does the battery used control the speed if I have no controller?
4. How do I power such a device?

Additionally if you have an idea on whether I sould, wind fishing line onto a spool, install a belt, have a wheel rub against a line - or anyway to get perfect motion please let me know.

There plenty of expertise on here. I'm sure somebody will chime in.
Have a look at Openmoco.org. This should be a goldmine for you.

Thank you so much, I had missed openmoco.org and these guys seems to be off the charts for this type of technology.