Yeah, they are. Was a real chore to get them painted as they fit really tight over the polycap like material they are molded around. I got around this by moving them to one side of the “rod” and took some material off of it, but still let enough on so there was some resistance so they didn’t slide against one another. Then slide them one by one to the other side of the rod to take material off of the opposite side of the rod. Hope this makes a bit sense.
To get them initially moving, I used a twisting motion and at the same time sliding them.
Good luck and happy building!