Looking around my local builders' merchants (Halls) for something
to use for a loading coil former I came across what is described
in their catalogue as a "plasterers' bucket" 460 mm (18 ins) tall,
330 mm (13 ins) wide at the top tapering to 280 mm(11 ins).
It is very strong (I can stand on it), and far more rigid than other
plastic buckets. It's made of a translucent whitish thermoplastic
about 5 mm thick and putting a piece in the microwave for 15 mins
didn't even make it warm. It melts with a soldering iron in exactly
the same way as the polyethylene in coax cable and has the same
slightly greasy feel. Also considerably harder than PVC.
So is it polyethylene? It cost 12 pounds as against 1.50 for the usual
cheap plastic bucket so maybe that's a clue. I've wound it with 4mm
Litz to make a variometer and am using it with the QRP rig. Measured
Q is over 500 using only plain single-layer winding.