Hornby do an 'Operating tipper set and wagon' which uses an end-door wagon and an electrically-operated tipping arrangement. Part number R8132. The end-door wagon is of a type used for coal. It does not appear to be available separately from the set.
Hornby also have mechanically-operated log loading and unloading sets, also a gravel wagon - both these are side-tipping rather than an underneath hopper type, at least for the gravel.
Regards,
John Webb
Hornby also have mechanically-operated log loading and unloading sets, also a gravel wagon - both these are side-tipping rather than an underneath hopper type, at least for the gravel.
Regards,
John Webb
