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Ohlsson and Rice company formed
"By 1941 Irv Ohlsson had teamed up with Harry Rice, and the firm of Ohlsson & Rice were producing a .19, a .23 and a .60 that were highly popular. No other engines at the time combined the reliability, ease of maintenance, simplicity of operation and unlimited life of the O & R engines. The Second World War put a temporary hold on their success, however, as all manufacturing facilities were turned over to military production. By the time the war shut down their production, they had produced about 75,000 engines.
As soon as the war was over, O & R got back into production. Even with a shortage of needed materials and machines somewhat worn out by 3-shift a day wartime production use, they jumped back into a market that had a seemingly endless demand for their products. Modelers were hungry to get back into flying, and O & R took advantage of the market by buying the machinery needed to meet the huge demand. By the end of 1947 their production had risen to almost a thousand engines per working day."
Link:
Model Engine BuildersIrwin Ohlsson