Xacto Knife Cap
thingiverse
I whipped this up on TinkerCad to replace the cap I lost on my old Staedtler blade. If it's too loose or too tight, just edit the ID. Everything else should work fine. If you do remix it, I'd suggest to make the id at the opening slightly smaller so it grips better. I printed it upside down in PETG and it printed fine with no support.
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