[G6Tanuki]

One from a year or so back: building a little HF antenna-tuner I needed a way to isolate the frames of the variable-capacitor and the roller-coaster coil from the metal case. I found a Tesco "Value" polythene chopping-board could be cut to size and, being about 1.5cm thick, provided a rather good solid low-loss insulating base.

Small offcuts of the chopping-board bolted to the front panel provide support-bearings for the two control-shafts. Polythene is a good material for use in un-lubricated bearings.