What the station does and what you need

OpenTag Station is a small touchscreen device you build yourself. You put a filament spool on it and it reads the spool's NFC tag, shows which Spoolman spool it is, weighs it, and saves the remaining filament to Spoolman. It also writes new tags from your Spoolman records and, if you use FilaBridge, can tell your printer which spool is in which toolhead. That part is optional.

Demo data. The picture is a rendering of the touchscreen, not a photo.

What it does

• Identifies a spool. Place a tagged spool on the station and it looks the spool up in Spoolman.
• Writes tags. Pick a spool (or a filament) from Spoolman and the station writes a blank tag for it in the OpenPrintTag format, then checks the tag and links it to the spool in Spoolman.
• Weighs and saves. The station subtracts the empty spool weight and shows the filament that is left. Nothing is saved to Spoolman until you press UPDATE SPOOLMAN (or turn on automatic saving).
• Clears tags for reuse. Erase a tag, remove its link in Spoolman, and use it on another spool.
• Assigns a spool to a toolhead (optional). With FilaBridge, tell the printer which spool is loaded in which toolhead. Tested with a Prusa XL; the touchscreen shows up to five toolheads.

Spoolman stays the record of what you own. The station reads from it and updates it; it does not keep its own inventory.

What you need

You need	Notes
The station hardware	A WT32-SC01 Plus touchscreen board, an NFC reader, a load cell with its amplifier, and the printed case or a platform you build. See the parts list.
Spoolman	Your own running Spoolman server that the station can reach on your network. The station is not useful without it. Weights are saved to Spoolman 0.26 and 0.27; see Connect Spoolman.
2.4 GHz Wi-Fi	The station cannot join 5 GHz-only or WPA3-only networks.
Blank tags	NXP ICODE SLIX2 (NFC-V / ISO 15693). NTAG and MIFARE tags are found but not read yet; other tag types are not seen at all. See Which tags work.
A desktop computer with Chrome or Edge	Only for installing the firmware over USB. Afterwards any browser on your network works.
A known weight	To calibrate the scale once.
FilaBridge and a printer it supports	Optional. Only needed to assign spools to toolheads. Tested with a Prusa XL.

From parts to your first spool

Follow these pages in order:

1. Parts list — buy the parts.
2. Wiring — connect the scale and the NFC reader, then check Power and print the case or build your own platform.
3. Install the firmware over USB.
4. First boot and Wi-Fi — get the station onto your network.
5. Connect Spoolman and FilaBridge — including the scale calibration and, on Spoolman older than 0.27, the two extra fields Spoolman needs.
6. Your first spool — write a tag, save a weight, assign a toolhead.

Two ways to use it

You can use the station from its touchscreen or from the station's web page in a browser on the same network. Everyday work needs no browser: identifying, writing, clearing, weighing, saving the weight and assigning a toolhead all work on the touchscreen.

The two use slightly different words. Most action buttons on the touchscreen are in capitals (WEIGH, MANAGE TAG); browser buttons are not (Weigh, Manage tag). The touchscreen's start page is Home; the browser's is Dashboard.

Touchscreen pages	Browser pages
Home, Weigh, Assign, Tag, Settings	Dashboard, Inventory, Printer, Settings

Some things exist in only one of them:

Only on the touchscreen	Only in the browser
Showing the name of the setup network	Updating the firmware
Choosing the printer from a list of the printers FilaBridge found	Factory reset and restarting the station
Setting a new access token when you forgot the old one	Downloading and restoring a settings file
	Testing the Spoolman and FilaBridge connections (Test)
	Choosing the 5 kg or 2 kg load cell
	Editing spools and filaments in Spoolman
	Removing a spool from a toolhead (Unassign)

The touchscreen never asks for the access token. The token only protects changes made through the browser; see Access token and network safety.