Ceiling mount multisensor housing with twist-lock mechanism

I set out to make a twist-lock mechanism, inspired by a simple mechanism I saw on a deoderant bottle. It was an interesting journey which took many days of testing to reach success. I would challenge you to make a mechanism that is better than mine, I am sure this can be improved!

The idea with the twist-lock is that you put two pieces together, and you just start twisting, and eventually you feel a “click” and it's locked together. This sounds simple but is surprisingly difficult to achieve. Firstly it needs a kind of guide-rail that means whatever angle you combine the two pieces, it will sit straight, and then guide one piece down onto the other as you turn. Then there needs to be some way to make it “click”. And I wanted it to print successfully without the need for supports which would change tolerances within the mechanism. In the main part (with LED strip) you can see a ring, and above it you see little tabs. These tabs needed some angled part underneath (as you cannot print in mid air) and this causes a lot of the challenge to get right.