Instructables user spookylean shows us how to make this cool little folding prop based on a weapon from the video game Batman: Arkham Asylum. He does it the labor-intensive but inexpensive way, cutting the profiles by hand from clear hardware store Plexiglas and then painting them black. I am too lazy for that and would probably just have them laser-cut from black plastic to start with. Embedded magnets lock it in the deployed position.
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