A push-fit socket for those semi-standardized garden hose quick connect things for 3/4" garden hose threads. It uses 6mm airgun bullets as latches. IT ACTUALLY WORKS AND HOLDS PRESSURE WITHOUT LEAKING though tolerances may depend on your printer, I printed it on a Taz 6. Please read the instructions.
Requires vitamins: 4 x 6mm plastic airgun bullets (i.e. airsoft), ABS glue.
Requires cleanup after printing.
Printed in ABS with general "medium quality" setting.
It may or may not require supports depending on your printer. I managed to print it without supports once, but that was an accident and may have been a fluke.
Sleeve Version Only
This is an improved version of https://www.thingiverse.com/thing:2422356 re-designed to the center spindle can print flat, which causes a big improvement in strength. But the stairstep pattern inside a horizontally printed tube won't perfectly seal.
push_0009b.stl includes a little shim that prints vertically - you're supposed to glue it inside the threaded section, for that perfect seal, since a horizontally printed part will be a bit rough inside.
Don't get it upside down, the wide end of the flange should point towards the ball bearing holes. Wipe up any excess glue.
Non-Sleeve Version Only
This is an improved version of https://www.thingiverse.com/thing:2422356 re-designed to the center spindle can print flat, which causes a big improvement in strength. But the stairstep pattern inside a horizontally-printed tube won't seal perfectly. Paint it with ABS glue to get a shiny surface which will work better.
Paint a ring of ABS glue on the very end of the threaded section, to get a shiny surface that won't leak when screwed to a hose.
Ream out the holes in the center part until the BB's can just barely stick through the side, but not so much that they fall through. The locking sleeve can now be slid atop as an extremely tight fit, becoming loose again (though nearly unremovable) once the balls are fitting into the locking grooves.
The locking grooves hold the BB's fast when the sleeve is in the locked position, preventing the other half of the quick-connect from leaving.
Like most garden hose things, use proper hose washers to prevent leaks.
As usual, sources at my site: http://burningsmell.org/3d/pushfit/