Tired of contact sensors that are glued to window frames, looking ugly and tending to fall off sooner or later – especially on frequently used windows or in changing temperatures? Mee too!

Luckily, I came across a design by chames.bont, which perfectly fits my needs - but for a different contact sensor. I started to adapt, modify, and remix the concept to better fit my own setup. Many thanks for sharing your work with the community.

This model mounts the contact sensor directly to the window handle, avoiding adhesives on the frame entirely. The result is a clean, reliable, and fully reversible installation that stays in place even with daily use.

I am a big fan of Tuya Zigbee contact sensors, mainly because they use standard AAA batteries. In my setup, these sensors have been running for over two years without a battery change, which makes them very practical for long-term use. They are also cheap and still doing their work.

I went through a learning-by-doing process. An earlier version mounted the sensor in the opposite direction using the backplate, but testing showed that the distance to the magnets was too large. Flipping the sensor and switching to a top slide-in design solved this issue and significantly improved detection reliability (my tests show a 100% detection rate).

The model has been tested on standard German window handles. Feedback, improvements, and remixes are very welcome.

BOM

This model requires 2×3 mm neodymium magnets. Optionally, you can use a small drop of glue to fix the magnets, although they are designed to be press-fit (I used glue as a precaution).

Printing Info

• I did my tests with PETG, which works very well.
• After completing the tests, I printed the final version in ASA, which provides excellent strength and UV resistance. If you have the option, I recommend printing in ASA for the best long-term durability
• I uploaded the print profile as PETG to allow more users to print it easily.

PLA is not recommended, as the model is under mechanical stress and may be exposed to sunlight, which can deform it over time.

After completing the tests, I printed the final version in ASA, which provides excellent strength and UV resistance. If you have the option, I recommend printing in ASA for the best long-term durability.

Key Features

• No glue or tape on the window frame
• Mounts directly to the window handle
• Reliable detection via rotating magnets
• Designed for long battery life sensors (AAA)
• Fully reversible installation
• Tested on standard German windows

Notes

• Designed for standard German windows
• Assembly guide included
• Use at your own risk