Pre-owned 1960s Muldivo Mentor Pinwheel Calculator for Repair. Carriage is stuck and will not advance. All other features fully working. Includes original instruction manual and grey plastic soft cover.

Step back in time with this beautifully engineered mechanical calculator from the 1950s - 60s. Long before digital tech, businesses, banks and schools relied on this pinwheel marvel to crunch numbers.

The Muldivo Mentor WSR 160 is a 1960s German-made, hand-cranked mechanical calculator, renowned for its high-quality brass pin-wheel mechanism and clever engineering. The machine itself was originally manufactured in the 1950s and 1960s by Walther, a German company best known for producing precision instruments, including the famous PPK pistol as used by James Bond. Walther’s WSR-160 pinwheel calculator was their top postwar model, featuring advanced mechanisms compared to earlier designs.

For the UK market, the British company Muldivo (established in London in 1912) acted as importer and distributor, rebranding the Walther WSR-160 as the “Mentor.” Muldivo had a long tradition of supplying calculators and often rebadged European machines for British buyers