SAT started own engine production in 1940 under Hercules licence. This together with tram building and 1942 started axle production led to lack of space in the factory area. The first plans of moving some of the production out from Helsinki were made already before the war. The plan was put into practice due to the war which made the factory located in the capital vulnerable to Soviet air raids. In 1942 the construction of new premises began in Karis, which was out but sufficiently reachable from Helsinki. Coach- and cabin building was transferred first, after which the tram production followed; building of lorries stayed exclusively in Helsinki until 1950.