Massaging Rolling Pin

Another massage tool. It's a print-in-place 'rolling-pin' style massager.

Why create yet another one? This one had a very specific purpose for me. While doing physical activities like squats, when I get down to about 90 degrees, a tendon behind my knee slips in and out of place, which can cause a bit of pain the next day. My physical therapist recommended using a tennis ball to roll my leg over to massage the tension out. Though, I'm no sports person, and have no sports balls, so this is the thing that I made to solve my lack of sports balls. It works very well for me as well.

This object is a Customizer enabled. I feel like the default settings are pretty good, but of course you could make the handle area longer/thicker, or make the ball bigger or smaller. One setting of note is the 'clearance.' This is the distance the inner rod comes up above the inner cavity. If you set it to 0, it will sit on the inner cavity, which may very well fuse the rod to the ball. A setting of '1' is