Wool / Yarn Winder support

The guide rod for the yarn on this Marrywindix manual wool winder keeps falling down leading to a yarn disaster.

https://www.amazon.com/Marrywindix-Operated-Manual-Winder-Holder/dp/B00R7GGTCI/

This piece fits over the guide rod and solves the problem.

See also this piece by http://www.thingiverse.com/scarabaea for the same winder: http://www.thingiverse.com/thing:1320067

Alternately, someone on Amazon had the excellent idea of just using a spring to push the arm out so it stays locked. But that person must not have a 3d printer.