Sprocket Chopping Knife
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My wife wanted a Chopping Knife since forever while she was nagging about something I've scrolled through instructables... Accidentally I said Yes to something.
The idea was to build one out of a old sprocket from my bike. It Took me something about 3h to build it. I was supplied with two coffee from my wife and used only standard tools like a drill and a angle grinder.
Find Some Sprocket
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I dive something like 5000-6000Km every year with my bike. These are 3100-3700 freedom units. The chain and sprocket are changed ~once a year.
For this projekt I'm using a SRAM x12 set...
Preparing the Sprocket
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... especially the 50 teeth (the biggest). Therefore the rivets needed to be removed. Then the sprocket was mechanically cleaned halved.
Grind Away the Teeth
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For the cutting edge we need to remove the teeth.
Sharpen the Blade
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To ease the process of having two identical parts I've used some screws to hold everything together. Then I've used my angle grinder to grind on a first edge. With a sharpening stone I've finished the sharpening for now. (I'll try to harden the blade in the future to further increase the sharpness)
Crafting the Handle
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As a handle I'm using some V4A steel which i found in my garden... don't ask. To mount the handle to the sprocket the same holes like the rivets before were used.
Stiffen the Two Blades
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To make the two blades as stiff as possible I've cut down some brass tube and added some screws. This way I have more then enough structure added and it feal like a solid pice of metal, zero flexing.