Perpetual Motion Machine: The real-life version of M.C.Escher's Waterfall

Step 8 5.2 wall of flume

The wall of the flumes is composed by two ABS plates indicating the shape of "walls" and 5~6 PVC pipes limiting the width of flumes.

To avoid leakage we need to stick PVC sticker on the top of wall. It also helps when we do the mapping later.