M30 x 1.5mm manual radiator valve cap

I recently needed to shut off one of my radiators manually, but I realized I didn't have the original plastic cap. I searched all over MakerWorld for a simple, reliable model, but I couldn't find what I needed. So, I designed this heavy-duty version from scratch to solve the problem for myself and anyone else in the same situation.

This is a robust, functional manual control cap for standard M30 x 1.5mm thermostatic radiator valves (TRV). This model is designed to replace lost or broken plastic caps and is strong enough to fully depress the radiator's valve pin to shut off the heat.

The design features a hexagonal head combined with an ergonomic grip, allowing for high torque by hand or the use of a standard wrench if the valve is stiff.

Features

• Aesthetic & Ergonomic: The balanced hexagonal shape provides a professional, "factory-made" look while ensuring a perfect grip.
• Dual-Purpose Design: Large hex faces for wrench compatibility and rounded flutes for a comfortable hand grip.
• Standard Compatibility: Fits most common radiators (Heimeier, Honeywell, Oventrop, etc.) with an M30x1.5 thread.
• No-Support Printing: Optimized geometry for easy printing without supports.

Material: PETG (Recommended), ASA, or ABS. Do not use PLA, as the radiator's heat will cause it to soften and fail.

Disclaimer

This is a DIY replacement part. While designed for strength, always ensure the material used (e.g., PETG) can handle your specific radiator's operating temperature. Use at your own risk.