This plugin allows connecting an HX711-based load cell to Octoprint to read out the current weight of the remaining filament.
You will need an HX711 breakout board and a compatible load cell. You can find these bundled together on Ebay/Aliexpress for roughly $8. Any load cell rated for more than 1kg and less than 50kg should work; I used a 5kg load cell with solid results.
See here for instructions on wiring up the load cell: https://tutorials-raspberrypi.com/digital-raspberry-pi-scale-weight-sensor-hx711/
This plugin assumes you connected the data pin to GPIO20, and the clock pin to GPIO21.
You will also need the bracket to connect the load cell to your printer:
- Regular Spool Holder: https://www.thingiverse.com/thing:3037926
- Spannerhands Spool Holder: https://www.thingiverse.com/thing:4834908
Install via the bundled Plugin Manager or manually using this URL:
https://github.com/techman83/Filament-Scale-Enhanced/archive/main.zip
Once you have wired up the HX711, it must be calibrated. This is a pretty straightforward process, and all you will need is an object of known weight. Attach the load cell to your printer with the printed bracket, then follow the instructions on the plugin's settings page.
If you would like weight messages published via MQTT, install and configure Octoprint-MQTT
Once it's configured correctly, this library will automatically detect it and start publishing messages in the following format:
baseTopic/plugin/filament_scale/filament_weight 171
NaN may be occasionally displayed in the interface when the weight can't be read correctly. The cheap boards vary in quality and are a little sensitive to vibration/power stability. Ensure the cabling is secure, you have a sufficiently sized load cell, and a good power supply.
Python 3 + Python 3 Virtualenv recommended
python3 -m venv venv
source venv/bin/activate
pip install OctoPrint Mock.GPIO
pip install ".[development]"
Running Tests: pytest -v