Meccano Chain - 3 - More Chain Drives

Meccano Chain Drive - 3

More Chain Drives

The Meccano chain can be used to drive from either side, so you can have multiple sprockets on each run of chain as shown below.

Note that any sprocket running on the back of the chain will rotate in the opposite direction. In the example above, the ratios will be 18:-14:28. So, if the left hand sprocket is input, for each rotation of this shaft, the centre shaft will rotate 1.28 times (18/14), but in the opposite direction. The right hand sprocket will rotate 0.642 times (28/18).

There is one more standard Meccano part which has sprocket teeth, this is the upper tray of the thrust bearing (Part 168).

This part has 73 teeth, which will allow another host of ratios ranging from 5.21:1 (with 14 tooth sprocket) to 1.30:1 (with 56 tooth sprocket), when paired with the standard sprockets. You'll need to attach a bush wheel (Part 24) to one side to allow the part to be attached to an axle.

73 Teeth may seem like an unusual number, but it is a factor of 365 (73 x 5), which is useful for calenders as there are 365 days in a non leap year.