I made this to wind up the 1/8" nylon rope on my canoe anchor.
Print 1x Cord Winder and 2x Handles. Then assemble with stainless hardware leaving the handles enough space to spin free. (I used epoxy to set the handle bolts into the body.)
I made the "points" sharper so the rope would wind easier.
I moved one of the handles to the middle to allow for easier winding around the center axis.
And I added a small hole opposite the center handle for the back end of the rope I use to be fed out of.
(This allows it to easily be attached to something else so you don't lose your anchor and winder accidentally.
IE. Imagine if you have the anchor down and the winder in the bottom of the boat. You unfasten the anchor line (fastened in the center of the rope at the depth you needed it) and you start pulling up the rope with your hands as the boat drifts. But your hands slip and lose their grip. The anchor drops and you are now in much deeper water. The line pulls tight against the cord winder and it goes overboard. It's not built to "self-unwind", and it's not bouyant enough to float the anchor so it sinks right along with your anchor.
If the winder is connected to something in the boat via the "start" of the anchor line through that hole the winder can't go anywhere. It's also not in the way since it's perfectly at the winding axis.)