How soon before making a fist will be outlawed? It might be used as a weapon, best we just cut it off, right?
As has been oft repeated: All you need to make an edged weapon is a material that will hold one and a way to make it sharp.
A knife or Shiv can be made by anyone out of metal, plastic, stone, etc.
All that needs to be done is get the material and sharpen it.
On a basic level, a weapon is anything that can be used to apply destructive force (preferably at a distance) . That can mean just about anything tree branch, rock, brick, laser, M1911A1, Thermonuclear devices, etc..
Bottom line WE CAN NEVER RID OURSELFS OF WEAPONRY. So there is no point in pretending that we can.
The only solution is to be armed to defend yourself be it criminals or governments.