How do I slow down a pocket door when opening and closing?
I'm currently installing a pocket door. It's a full 1.75" exterior door thickness, flush door that weighs 120 lbs (plywood facing and oak rails and stiles and oak edging.) I built the door myself (cost me 10% against the cheapest bid I got for the door.) I am using Johnson 200 series rollers and I-beam for the door. It rolls VERY easy. Easy enough to break finger bones. So this quickly became a serious safety issue for me. Luckily, before I set to finishing the pocket door wall.

I am using carpet samples (free) on the floor inside the pocket. The carpet is attached inside a separate piece of "furniture," in the sense that by removing the door trim, I can remove the pocket door and then reach inside, unclip the wood box (3/4" high, 32" long, 3.5" wide) that holds the carpet samples, replace worn samples, reclip the box back against the floor inside the pocket, place the door back, and retrim the door. I can easily set the resistance this way (packing several strips of carpet on top, if needed) and appropriate carpet samples will be available in perpetuity.

Also considered using pile weatherstripping as an alternative idea. But the carpet really seems to work better and only wears against the bottom of the pocket door which no one sees or cares about.