Nefit Smartline controller knob

Replacement knob for Nefit Smartline gas heater controller.

To maximize strength, the knob shaft must be printed horizontally, requiring support.
All other details are designed with an angle, so with the correct support angle setting, only the knob’s edge and shaft will get automatic supports.

Optionally use a sharpie to color in the arrow.

The design maximizes strength within the available space, but the retaining clip remains fragile.
Carefully remove any remaining broken parts (e.g., using a sharp needle) before installing the new knob.
Install only once, as repeated installation seems to eventually damage the retaining clip, because the plastic is stressed beyond its yield point.

The knob was designed in Rhino3D. The original .3dm, as well as .stl, .obj, .stp, and .igs files, are included.