Plastic Knuckles
thingiverse
I have designed these "brass" knuckles with FreeCAD and I am pretty satisfied with the results, since I still am pretty new in the 3D printing universe. 80% or higher infill is recommended in order to obtain a print dense enough. Also, the size depends on how big your hands are. In my case it was 90% the original size, which I strongly recommend. IMPORTANT: This is intended to be used only as a self defense weapon in an extreme emergency case. Do not use it to harm anyone, as it could cause serious injuries.
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