paper knife - knify knife
thingiverse
This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/4tBuqF6i46Q Simple easy knife, printable with no support. I added a 8mmx3mm magnet to make the knife stick on my metal frame desk. I printed it with 0.3mm, so it is very rough. I think i will reprint it with 0.1mm. But it works quite nice for opening letters!
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