Roger Hill, Transvaal Meccano Guild
The centre of the differential is formed by sandwiching a coupling between two 1½" narrow strips. A short threaded pin is inserted into the coupling and on the threaded end of this is fixed a collar secured by a nut. The assembly is held together on two threaded rods and fixed by nuts. The ends of the differential are a 1½" bevel gear (the crown wheel) and a bush wheel or wheel disc. These are secured to the threaded rods with nuts. This forms a very compact, robust frame for the differential eliminating twist. Two ¾" contrate gears are attached the the coupling by pivot bolts with washers as spacers if necessary. The contrates must rotate freely on the pivot bolts. The two half shafts pass through the bevel gear and bush wheel respectively and each hold a ½" pinion. They are journalled in the centre holes of the narrow strips at the centre.
© Copyright Roger Hill