The age old question - do you beat on an open shed? closing shed? closed shed?
I thought I beat on a closing shed until I really started thinking about what I was doing and observing what was actually happening. And then I began thinking that at the moment of impact, the shed was in fact closed.
So I set up the video camera so that it was recording what was happening behind the beater on a level with the warp in order to see.
And now you can, too.