009 Coal hopper style wagons,
These are loosely based on the standard gauge coal tub displayed at the Beamish Industrial Museum in the north of England. They are of a wooden planked construction reinforced with metal straps and bolts, built on a stout wooden frame. I have included a pair of basic universal couplings, but other types may be used if preferred.
The chassis has a clip-on base to hold the wheels. I would recommend 6.2 mm metal rimmed wheels with 7 curved spokes with the pinpoint bearings removed. These are available from Dundas Models ref PN58 for 2 or PN59 for 20.