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.