Replacement female coupling ring for a Gardena garden shower. Designed from measured dimensions of the original lost part.

Features:

- True helical threads (ISO 60 deg profile, M27x1.5)

- 11 grip bumps around the exterior for hand tightening

- 3mm top lip with through-hole for aluminum pipe insertion

- Rounded edges, chamfered thread entrance

Dimensions:

- OD: 35mm, Height: 19mm

- Pipe hole: 21mm

- Threaded section: 16mm deep

Tolerances:

- $slop variable controls all clearances. Default 0.20 works for most PETG prints. Decrease to 0.15 for tighter fit, increase to 0.25 if too loose.

- Adjust in ring.scad before exporting.

Printing:

- Material: PETG

- Infill: 100% (structural thread walls)

- Layer height: 0.15mm

- Supports: not needed

Requirements:

- OpenSCAD 2021.01+

- BOSL2 library

Export:

openscad -o ring.stl --export-format binstl ring.scad


I used PI AI agent with local model to help me create this. You find the used skill attached.