What it is
Shredded waste always hides a bit of steel: screws, staples, springs, threaded inserts. Steel wrecks extruder screws and blunts knives. It needs to come out early, and it is worth weighing on its own, because clean scrap steel is a stream, not rubbish.
M2 is one bar holding ten strong neodymium magnets on a steel strip, used three ways:
- Chute. Slide the bar under the floor of a printed chute and pour the batch down it. Steel sticks; plastic slides past. Slide the bar out over a cup and the steel drops off.
- Rake. Put the bar in a closed sleeve and sweep it through a tray of flakes. Pull the bar out, the steel falls.
- Wand. For deep bins and single pieces.
There’s even a zero-print fallback: any salvaged magnet in a zip bag.
Why it matters
It is the cheapest useful machine in the whole recycler and a good first build for a curious family — with an adult, because these magnets pinch hard and can shatter.
Safety
Eye protection. No pacemakers near the bar. Keep phones, cards and drives away. Store it on a steel keeper.
Where it stands
Designed, with printed parts drawn and rendered. A bigger version, built into the head roller of a conveyor, is designed for 2027.
Les plans sont gratuits — the plans are free.
