Sump pump hose coupling

Connects a 1-1/2" corrugated hose (common for sump pumps in North America) to a 3" threaded PVC cleanout fitting.

(I needed to make that connection reliably, with very little vertical space. See the third photo - this was the situation I inherited. No further comment.)

This coupling is not watertight; it fits the case where your sump pump hose is draining into a wider pipe that will drain downward. I think allowing a little wiggle in the connection improves durability, because otherwise the force of water flowing and stopping intermittently would be transmitted more directly to the cap.

I printed this in PLA once (pictured), and it cracked after some months; not sure whether a work crew banged it up accidentally or it died due to stress. So, I printed the replacement in glass-filled PLA, which seems like it's doing fine. (Five years later: still fine.)

A couple of contractors have needed to replace or modify the hose since I installed this, and they both figured out how it worked without asking me, which I took as a design victory.