Heidi, I would love to see pics of the pots you are creating but also, a question: why did you choose to put your orchids in pots without potting medium? I have dropped orchids in pots without potting medium and they have grown but most people use the medium as a way to keep the roots moist enough and the humidity up. That seems to be your major concern?
Given the opportunity (no disturbing the roots) the roots will attach to the inside of your 3-d pots.
One more question: what kinds of orchids are you growing? Here is one of my mini-terrariums (about 1 gallon) with 2 Masdevallias and a Davallia fern.
