Revisiting - Ratchet thoughts

This is an addictive hobby and one's thoughts keep turning to odd bits and pieces. 

I do not like the idea of Clayton's (noisy football type rattle) ratchet, but I think it's attachment to the Minute wheel is much better than what I had proposed.  Why?

Well if we look at the opposite diagram with an exaggerated clearance between the (green) winding drum and the (yellow) arbor.  Despite the gap, the right side of the drum will always be at a constant distance because the weight will make sure it is always pulled to the left.

But a wheel (not shown), attached via a ratchet with a single pawl (the red spot) will move in an elliptical orbit and not a constant distance to the next wheel.

 
I must therefore change it's design slightly.

a) there must be 9, not 8 clicks for the 3 pawls to engage with on the ratchet

b) each pawl must be sprung to always engage.

Furthermore if I attach the ratchet to the minute wheel, instead of the pawls (as is normal and in my design), it means I do not need the supporting disc on the front of the Minute wheel (to keep it upright if I'm to overbore most of the inside of the holes to reduce friction), as the ratchet will achieve the same purpose.

My design had the elements of the Minute arbor (going from front to back) as ['+' signifies they are connected]
          End cap, Supporting Disc + Minute Wheel (with pawls attached), Ratchet + Drum End + the Drums etc. - 5 elements before the Drum.

I can now have
          End cap, Minute Wheel + Ratchet, Drum End (with pawls attached) + the Drums etc. - 4 elements

and I can now attach the cord through the Drum End piece, rather than have to drill a hole in the actual drum - much easier.

I do find it useful to write out my design thoughts - now I must go back to revisit and change the design before getting down to the serious stuff of actually making something!

However I have failed to achieve my objectives at this stage of the project.  There were a number of reasons I decided to write this diary.  First because I think it helps to put things down on paper and I have an appalling memory, so re-reading it helps me.  Secondly it may help others like me, who are first timers and manage to find this web site.  But lastly in the hope that others may give me help.  In this last respect, the response for advice has not been forthcoming despite postings on a couple of forums.  In most other hobbies people share their knowledge, but I have not managed to find them - great shame, I will have to potter on in the dark.

 

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