darning egg or mushroom, Stopfei oder Stopfpilz

__A simple darning egg or mushroom, printable without support.__

At home we had a darning mushroom made of wood and I remembered this useful tool, so I designed one to print on FDM machines (i.e. Ultimaker, RepRap,...). It is designed for function and easy printability and not primarily for good design. I tested it and it works pretty well. And I think the design is at least ok while the _Darning egg or mushroom_ is in the sock (see below for details). ;-)

_What is a darning egg or mushroom?_
A darning egg or mushroom is a tool to help fixing holes in socks. It is a hard, round object mostly made of wood or plastics which is inserted into a sock while darning (repairing) it. The darning egg makes it easier to stitch over the hole. With the help of the darning egg, the sock doesn't get deformed while you stitch, and you will not accidentally stitch two sides of the sock together.

_How to use it?_
You put the darning egg in the sock beneath the hole and stretch the sock and