Through repeated sharpening of the bevel, the front flat on the back of a Japanese blade will begin to disappear. The solution is to tap the layer of soft steel above the cutting edge to press the hard steel downward slightly.
Thank you for the video! I read Odates book years ago but never had the confidence to try it. Today I tapped out a plane blade and a chisel. It really saved me a lot of grinding and metal. I hope there will be more videos with Andrew Hunter. Due to the Shop Talk with him I gave my japanese planes another try. Greetings from Germany.
Beauty!! Thanks for the demonstration. Ive just bought a japanese knife for leathercrafting and i was like what i am going to do when the edge gets near the Ura. Cheers!!
Simone Camplani I learned of my regrettable name translation in college when I had Italian neighbors. They said if someone was "Ben Strano" they were the village idiot. Can't argue!
I would have to offer, checking for flat on a sharpening stone even if flattened is not really adequate. Stones wear fast. A truly flat fine grit diamond stone much better for this purpose or an old fashioned kannaban probably best .
So here is a question, I bought a few years back a used Kanna, and the blade hollow is quite small or I should say the flat area, especially the corners are quite large, assuming they got that way because the previous owner didn't tap out his iron, and was just grinding away to keep a flat edge and the hollow off of the edge... How does some one brings back a narrow edge and narrow "corners"??
As I understand it from my time with Andrew, there really is no going back. If you're an online member of FWW you can check out this article www.finewoodworking.com/2017/02/08/get-to-know-japanese-handplanes , but I'm almost certain that's when a blade is considered truly "tapped out" and your best option is to invest in a new blade.
