The Filament Rack

Filament Spools don’t stack, so a drawer full of them clutters fast. The Filament Rack is a bookshelf-style shelf with 8 slots (2×4) built to hold them.

A printer fed by a rack (directly or over MC3D Cable) shows that supply in its GUI: the FU gauge tooltip adds a “+N FU via rack network” line, so a near-empty gauge with a stocked rack never reads as “out of filament.”

Storing spools

• Right-click the rack with a spool in hand to shelve it.
• Right-click with an empty hand to pop the last one back out — last in, first out.

Shelved spools render on the front, each tinted with its tier color, and the shelf visibly fills in as you stock it. It also emits a comparator signal scaled to how full it is.

A backup reservoir

A rack is also a Filament Unit reservoir. When a printer or fabricator runs out of its own docked spools mid-print, it automatically pulls FU from a rack that’s touching it — or one wired to it with an MC3D Cable.

Docked spools always feed first; the rack is the reserve.

Down-only tier rules still apply: a higher-tier spool can pay lower-tier costs, never the reverse. Keep one next to every printer as a backup tank and your prints won’t stall halfway.