The concept is a little confusing! So a plywood model helps to make it clear
(I made the model after getting the design wrong twice!)
The blank is first mounted centrally and the top "washer" shallow hole is formed
The blank is rotated 90° and re-fixed in position 2. Note the counterweight bolt
Moving to position 3, the third hole can be created. A variety of skews is used
The fourth hole is formed at the bottom. The counterweight is a heavy 10mm bolt