RMH vertical-auger mixers: Tubbies make breakfast, lunch & tea In outline, there are three main choices when it comes to mixer wagons: Horizontal-paddle machines, horizontal-auger designs and vertical-auger mixers. Featured here, the latter vertical types first appeared around a decade ago, with early model capacities spanning perhaps 8m3 to 14m3. James de Havilland assesses entry-level used buys, and provides some ‘to look for’ pointers