Hi Archit Patel, and welcome to the forum

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I know that I started this monster thread, and when I did I did not imagine what it would develop into, but what I do know is, that many of those participating enjoyed it very much, and at the same time also learned a lot. This is what we all hope, to enjoy ourselves and to learn – so it was a good and interesting thread.
I don’t know much about metallurgy, so my guess may be totally wrong, but I would thing that the difference between the knife made out of a file, and the one made out of a Leaf Spring is, that the ‘file’ knife was treated with a grinding stone, and the Leaf Spring knife was probably not, or at least not so intensively. Is that correct?
Jens