OpenSpool Makes Proprietary Filament a Thing of the Past

Bambu Lab printers have become massively popular in the last few years for good reason: they’re very easy to use and work very well. But one major complaint people have with Bambu Lab printers is that they’re largely proprietary and kind of lock users into the ecosystem. If you want to take full advantage of Bambu Lab’s AMS, for example, then you need to buy Bambu Lab filament that it can recognize with its RFID reader. But what if you could have all of those advantages while purchasing any filament you want? Now you can, thanks to the OpenSpool Mini device.

OpenSpool is an open source RFID reader for 3D printers, designed by Spencer Owen to eliminate the proprietary barriers associated with filament detection systems. Bambu Lab’s is the most noteworthy, but other manufacturers are experimenting with similar systems.

This goes both ways, so you can read Bambu Lab filament RFID tags for use with other 3D printers or you can put tags on any filament to use with Bambu Lab printers. To be clear, you can already use any filament you want with a Bambu Lab printer — it is just that you won’t get automatic filament detection. OpenSpool enables that automatic filament detection, even if you are using other brands of filament. It is, essentially, spoofing the tag ID.

OpenSpool is very much still in development and the read/write support for each printer and filament tag type is limited, but the project is progressing nicely and we expect to see that support grow.

If you want to give OpenSpool a try, you can build your own device right now using the open source files. But Owen is also offering several options on Tindie for those of you who would rather save some time. You can purchase the bare PCB so you don’t have to have one fabricated, purchase a kit, or purchase a fully assembled device. The prices are surprisingly low — Owen should probably increase those to better cover his costs, but you can take advantage of his generosity for the time being.

The device itself is based on an ESP32 development board paired with a PN532-based RFID reader. Those go in a simple 3D-printed enclosure that looks nice and is designed to sit next to the printer (or the computer that controls it). The ESP32 runs OpenSpool firmware developed by Owen and he even created a web tool to make flashing and configuration as easy as possible.