This is another version of the thumbwheel to replace the m3 wingnut on the Wanhao Duplicator i3 / Cocoon Create / Monoprice Maker Select.
It requires 4x m3 nuts to install. The nut recesses are quite tight, i recommend using long nose pliers to press them into place.
I also reccommend using this in conjunction with a locknut underneath the heated aluminium to stop the m3 bolt from spinning.
I prefer the larger wings, they are easier to turn finely than the more popular round style knurled thumbwheels.
Edit: Due to feedback/comments, I have added a smaller version which should clear the printer frame in certain cases where the original size was running into things, although I had no problems with the original size.
Edit: For any further changes, you can use this link to make a copy and edit using OnShape:
Edit: as requested, I have added 5.25mm and 5.75mm hex holes to allow for different types of m3 nuts and for various printers undersizing/oversizing holes.
Install m3 nuts
After printing, use a small hobby knife to cut away any excess plastic inside the m3 nut recess, and use long nose pliers to press the m3 nuts into their new home.