by romanjurt, published
A six Pin key 35mm diameter to open a cap nut on a new ER 20 Holder
Seems to be rigit enough and works. Long term testing still in progress...
This thing was made with Tinkercad. Edit it online https://tinkercad.com/things/92Gc0Wb93CI
i did print it with 30% infill and 1.2mm walls.