War indemnity work and rebuilding concerned the whole of Finland. Plane factories also began making war reparation products as far as possible. The situation was tricky because there were no products on the war indemnity list that were previously manufactured at plane factories. The greatest need was for heavy metal industry products. Instead of aircraft, the factories began manufacturing products that no-one had previously made in Finland. For example, in Kuorevesi they designed various kinds of transfer wagons for the plywood and timber industries and a pulp density adjuster for the pulp industry.

After the war, the Air Force did not need as many aircraft as before, nor was the economical situation favourable towards orders in the plane industry. In order to stay in business, the aircraft factories had to come up with products that could be manufactured using the industry's materials, wood and aluminum, and that could be made using the know-how gathered from making planes.

Among the products manufactured by Veljekset Karhumäki Oy were canoes, woodworking planes and metal tools. There was also plenty of farm machine repair work to be done in the surrounding countryside. Valtion Lentokonetehdas in Kuorevesi made such items as aluminum washbowls and milk jugs, wooden clock and radio cabinets, Pelva linen spinning machines, hairpins and file mechanisms.

When airplane production was on ice at the end of the 1940s, very little design work for new planes was done. Development of a new passenger aircraft was started as collaboration between Veljekset Karhumäki Oy and the Valtion Metallitehtaat metal factory. The development team included Uuno Karhumäki, Matti Hahka and August Puukko from the Karhumäki factory and Torolf Eklund, Johannes Joensuu, Oiva Lounivuo, Toivo Mäntysalo, Aaretti Nieminen, Paavo Paitula, Olavi Raitio and Karl Konrad Wessman from Valtion Metallitehtaat.

The working name of the new aircraft was Karhu-47. It was a four-seater, mixed construction, high wing plane, which could be used both as a land and hydroplane.
The new Karhu took off on its first flight on 20 July 1948 piloted by Uuno Karhumäki. The plane type was named Karhu-48 and two planes were built. The nickname of the first one was Nalle and the second one was Tavi. Production of Karhu-48 petered out after the import of cheap surplus aircraft was freed. The Karhu-48 can be seen at the Finnish Aviation Museum in Vantaa.