"Bruce" wrote in message
...
Hi Keith

What is your shaft diameter? Ours looks woefully inadequate - I have not
measured it but the Mk 1 eyeball indicates around 30mm (slightly more
than one inch)

Bruce

From memory it's not much more - a standard lorry half shaft. It only takes
'twisting' loads, as the drum runs on the normal wheel bearings in the end
of the axle casing. If it can take the semi-impact loads of a lorry driving
over rough ground, I can't see any difficulty with the relatively smooth
application of torque for a winch launch.

(Observations only from a 'guesswork' perspective. The winch was already
constructed when I joined the club about ten years ago, and I haven't seen
anything other than what is visible from the outside. The system works by,
as somebody else has said, pushing one half shaft in to engage the spline in
the diff, which causes the other half shaft to be pushed clear of its
spline, presumably by an interposed spacer.)

Keith