This Thing is a replacement plug and cap for the large inflate/deflate port of a big inflatable kids pool. It has two parts:
The cap part is a remix of Inflatable Pool Cap by jag. Thanks to the publishing of the openscad source for that Thing, it was a simple tweak to change to a round exterior (instead of hex) and set more stepsPerTurn / $fn for higher resolution curves on the threads. (I chose 120 steps per turn instead of the default of 24 steps per turn, which gave a little smoother result given the overall size of the part.)
A shout out as well to syvwlch for developing the awesome and useful screw library. That library makes the threads in the cap, so be sure to download it if you want to tinker with the openscad source for the cap.
Monoprice Maker Select v2.1 w/Klipper firmware
The threaded cap benefits from the extra resolution @ 0.1mm layer height if you can manage it. I printed at 100% infill to keep it strong.
The plug is less demanding and would probably print fine at 0.2mm layer height and whatever infill you use for solid objects. I used 0.1mm @ 30% infill for my plug.
(Klipper replacement printer firmware is awesome, check it out here if you haven't heard of it!)
Lost one of the three plug + cap combos for our inflatable pool, making my kids sad.
Went browsing Thingiverse for design ideas, hoping to find a parametric threaded cap that I could, through much trial, error, and use of calipers, eventually get to work as a replacement.
Instead, beyond all hope, jag had designed an actual identical replacement cap, and with openscad source! Tweaked a few things in the openscad file to make it rounder inside and out.
Unfortunately that only met half my need - I had also lost the plug that goes under the cap, so I pulled out my calipers and whipped up one of those in DSM.