Drop valve drive

The pinion driving the quadrants on the flywheel is a 16DPx36T screw cutting gear change wheel from my Raglan lathe. Any set of 16DP hange wheels from old scrapped back geared screw-cutting lathes such as Myfords, Boxfords or South Bends provide a source of several alternative gears rather than only quadrants and the 16T pinion in the Meccano system. A boss can be made to reduce the hole in the gears to suit Meccano or any HD axle system. Change wheels are available at s/h dealers.