I have a Dolce Gusto coffee machine and I use it with a set of reusable stainless-steel capsules. These capsules need a place to rest to cool down and pour out the water trapped inside.
Inspired by several other coffee knockbox, I made my own to handle my capsules.
Used capsules can rest on the top plate for several hours while they cool down and the water pour out of the hole. Afterward I can open them and take out the coffee (now solid enough) and drop it below.
The extra water will pass the internal filter and ends in the final outer container. This way I lower the risk of mold forming on the coffee.
Be aware that capsules are hot when resting on the top plane. I would suggest use PETG. In my case I simply made the top plane thicker since I have only PLA at home.
Credits:
alessandro.calzavara