I get a lot of questions about making these mechanisms out of materials other than wood. Metals such as aluminum and brass, and various other materials like MDF perform nicely. I even proved that low quality ply will work well when I used the rotten, termite infested, moldy ply from a fallen down chicken coop to make a clock. I wanted to show that these mechanisms are very forgiving of the materials used. That chicken-coop-clock looked really bad, but it ran.
I'm not familiar with Perspex. Had to Google Perspex and found it is an acrylic sheet. Some guys have already made my designs in acrylic and they all have reported that the internal friction of acrylic is very high. This means a lot more drive weight was necessary to overcome the internal friction and drive the mechanism. Excess drive weight always puts stress on the frame and arbors.