Back in the early '70's we used to manufacture_supply parts for the Rotothresh combine from the loewen Mfg combine parts plant. Still have brochures_literature_drawings on file, but don't remember quantities. There were very few made.
PAMI tested one when they were in production and here is the summary of that report that I copied off of the Alberta agriculture site. I think they were a bust, and they didn't last long. Summary of Western Roto Thresh Self-Propelled Combine Functional Performance: Functional performance of the Western Roto Thresh selfpropelled combine, was good in dry grain and oil seed crops. Functional performance was fair in tough and damp crops. Capacity: The MOG Feedrate* at 3% total grain loss varied from 11.1 t_hr (408 lb_min) in 3.58 t_ha (53 bu_ac) Neepawa wheat to 7.6 t_hr (279 lb_min) in 2.87 t_ha (53 bu_ac) Betzes barley. The capacity of the Western Roto Thresh was similar to the capacity of the PAMI reference combine for a similar total grain loss. Grain loss from the separating drum limited capacity in most crops. A reduction in grain loss over the separating drum would have permitted higher combining rates. Cylinder loss was usually small and aspirator and shoe losses were insignificant in comparison to the separating drum loss. The aspirator removed from 70 to 90% of the chaff before the shoe, resulting in increased shoe efficiency and reduced grain loss on side slopes. Engine and Fuel Consumption: The engine had ample power for all conditions. Fuel consumption varied from 27 to 32 l_h (6 to 7 gal_h). The rotary radiator air intake screen performed well, preventing radiator plugging even under adverse conditions. The engine started well. At temperatures below +5C, ether was needed to start the cold engine. Ease of Operation and Adjustment: The steering system was excellent for field operation. It was possible to pick most sharp corners formed by self-propelled windrowers. Most controls and instruments were conveniently positioned. All controls were responsive. The cab was adequately pressurized and relatively dust free. The evaporative air conditioning system performed well but needed routine maintenance. Sound level at the operator station was about 94 db(A). Header visibility was very good both in the daytime and at night. Grain tank visibility was good. Rear visibility was restricted. The rear view mirrors were needed for road travel. Road transport required caution since the short wheel base created a choppy ride. The maximum road transport speed of 22 km_hr (14 mph) was adequate. The unloading auger was slow, taking over three minutes to unload the 4.6 m3 (127 bu) grain tank. The Western Roto Thresh was quite easy to adjust for specific field conditions. Adjustment would have been easier if return tailings could have been inspected. The optional shaft speed monitoring system was helpful by warning the operator of malfunction. Ease of servicing was good. The cylinder, table auger, and feeder all were positive and aggressive. Plugging was infrequent, even in damp crops. Unplugging the cylinder was inconvenient since access was through the bottom of the grain tank. Unplugging of the separating drum and drum fan also was inconvenient. The stone trap stopped most stones before they entered the cylinder and was fairly easy to clean. The Melroe pickup had excellent feeding characteristics, delivering the crop beneath the table auger. Operator Safety: No serious safety hazards were noticed when operated according to the manufactuer's recommended procedures. Access to the cab was hazardous, especially for older operators. Operators Manual: The operators manuals provided adequate information, including a list of standard replacement bearing and drive components. Mechanical History: Durability problems occurred with the crankshaft extension coupling, the cylinder drive and the shoe hangers. *MOG Feedrate (Material-Other-than-Grain) is the mass of straw and chaff passing through the combine per unit of time.
the roto -thresh was subsidized by the saskatchen government while in production and when that was removed they shut down.they were selling for less tha it cost to build.they had a 48 inch john deere cylinder and new holland seives but i worked along side a 750 massey combine and could outwork it with the rotary technology-the ony drawback was going down a long hill you had to turn around and empty out the straw-they had short stubby drive wheels and if you went up a very sharp short hill sometimes the wheels would spin and the combine would bounce and water would splash out of the cab cooler and you would get wet.they started with 3145 cat diesel-then upgraded to cat 3208-they used about 3 gallons an hour so were very cheap to run-they originally came with roto-brush pickups but they were junk-the fibre glass brushes rotted from the sun-i bought a demonstrater when the company shut down about about 1976 and used it for several years-there was very little maintainence and no problems and less grain loss than other combines-im retired on 40 acres and wish i had one to play around with.maybe i could find one stored away.i still have the operators manual.