So here is my extremely quick and dirty improvised knock box. It may not pass the wife test which is lucky that I am single but it does the job.
Equipment - 1 small metal bowl, 1 dowel 2-3cm larger than diameter of bowl, 1 large 2 small rubber bands.
Put one large rubber band around the bowl
Loop 2 small rubber bands under the large and feed both loops through dowel
Done
Equipment - 1 small metal bowl, 1 dowel 2-3cm larger than diameter of bowl, 1 large 2 small rubber bands.
Put one large rubber band around the bowl
Loop 2 small rubber bands under the large and feed both loops through dowel
Done

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