How this thread works? 1

I think you'll find what's inside the nut is more interesting. It looks as though they may have a flexible element in there which kicks over at the end of travel and then follows the reverse thread back to the start.
Just guessing.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

It's sometimes called a "level wind guide" or "level wind mechanism" or "reversing screw" or "traversing screw"

This is a video of a larger version:
Here's a view showing how the pawl fits into the reversing screw:
A schematic view:

Thank you 3DDave!
That is the solution and thank you for the quick answer!
Great forum!