Meccano Chain - 1 - Chain Drive

Meccano Chain Drive - 1

Chain Drive Sprockets

Meccano chain and sprockets are another very useful way of transferring drive from one shaft to another.

Both the shafts will rotate in the same direction. The ratio between the two shafts is calculated by dividing the teeth on each sprocket. In the example above, the left hand sprocket has 28 teeth, the right hand sprocket has 14 teeth, so the ratio will be 28/14 = 2:1. The shafts can be any reasonable distance apart, as the chain length can be adjusted to suit.

There are 5 different sprockets in the Meccano system, as illustrated below. They range in size from ¾" to 3" in diameter.

From the smallest to the largest, they have 14; 18; 28; 36; 56 teeth respectively. If the two sprockets are the same number of teeth you'll get a 1:1 ratio, otherwise you can pair any two sprockets to get the following ratios:-

The sprocket details are as follows :-

14 Teeth (Part 96a) ¾" diameter.
18 Teeth (Part 96) 1" diameter.
28 Teeth (Part 95a) 1½" diameter.
36 Teeth (Part 95) 2" diameter.
56 Teeth (Part 95b) 3" diameter.

Note that part 95a and part 95b have large ½" diameter bosses fitted, so you will need a long grub screw (Part 69b) or set screw (Part 69) to secure to the axle.