Metal scrapers in the classroom 3D printer bin?
Our position, and the 'but they work' counterpoint.
Our position
A metal blade on a PEI build plate scratches the plate, which ruins adhesion permanently and ends with you buying a new plate. Worse, metal scrapers are the #1 source of 3D printing injuries. Kids always default to the 'strongest-looking' tool in the bin. If a metal blade is in the room, eventually a kid will use it to pry a stuck part, slip, and cut themselves. Bambu plates release parts with a gentle flex - the plastic scraper is almost never needed.
Other voices
Reputable sources worth reading before you decide. Labels reflect our honest read of each source's general stance, not direct quotes.
Bambu Lab official plate care guide
Broadly agreesBambu's own maintenance documentation recommends plastic scrapers and warns against metal implements on PEI surfaces.
Prusa knowledge base
Broadly agreesPrusa's documentation treats metal-blade prying as an advanced-adult-only maneuver, with explicit warnings.
3D printing enthusiast forums
Nuanced / mixedAdult hobbyists debate this regularly. Some argue a metal spatula with careful use is fine. In a classroom, the 'careful use' caveat is unenforceable.
Heritage Ender 3 / bed-knife workflow
Pushes backOlder printer communities grew up with glass beds that tolerated metal scrapers. That workflow does not apply to modern PEI flexible plates.