Well that went well. I cut out a sprocket and pawl with my CNC and slapped together a prototype with the spring I have on hand to test it and it works!
For the test, I just cut a slot in a dowel axle and attached the spring to the back of the temporary mounting board. Here it is as if all of the hose has been fed out. The spring I have will wind 6 revolutions which I think is the minimum required.
The only issue I have with this iteration is that if you reverse direction as if you are going to pivot to the locking position while the pawl is in the locking pocket rather than in a switching pocket, it binds and locks. It may just be friction between the rough surfaces of the sprocket and pawl and I suspect that it could release spontaneously. It could be that sanding it smoother and applying a slippery finish and wax would prevent that but I may have modify to the locking pockets to make the angle a little lower so that it slides more easily back into the switching pocket behind it. Not a big deal.
Anyway, this looks like it is going to work. Now to figure out how best to mount the spring.
--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.
