I bought this kitchen utility knife (actually 2, a large and medium knife) at a farm show a few years back. The only reason was the top blade slice tomato and onion rings easily for the perfect thickness for hamburger builds. As you can see it is a cheap make but using it for a few years now. The blades is sharpened with a single bevel (one side only).

How do I sharpen the blade. Specific the upper blade as my knife sharpening tool is double bevel device and does not fit in the gap to sharpen the top blade. I did noticed the rivet holding the 2 blades together at the front. One thought is removing the handle to access the top blade. It seems the tang is tapered to the rear and just bent over to prevent it from coming loose. I would have a locking pin fitted or a nut at the back for ease of removing the handle for future sharpening. How difficult would it be to drill a hole through the tang for a locking pin? I know some knifes are very difficult as stainless steel is used.

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