I am re-doing the airline setup for my aquarium. I needed some of the little airline hose inserts and didn't have any, so my wife said "Why don't you print some?". I looked to do this, but couldn't find any pre-made STLs, so I took to designing them myself.
These were designed in Shapr3D. I measured an existing airline flow control valve and determined that the outside diameter of the nozzle tip, was 4.2mm, with a 2.5mm inner diameter. I replicated this as close as possible, with the nozzle starting at 7mm with a taper down to roughly 4mm and an inner diameter of 3mm.
I recommend printing these in PETG or another non-soluble filament (PLA will dissolve in the water over time, while not harmful to the fish, it will cause some grief).
I printed these at 0.15mm resolution at a speed of 70mm/s. I use Overture PETG with a recommended range of 230 - 250, I printed these at 245 to reduce stringing, you will likely need to come back with a heat gun after the print to clean them up.
I also recommend using organic supports on the T & Elbow and printing them upright, this gave the best quality IMO. See the pictures for ideas.
The author marked this model as their own original creation.