I don’t know about you, but I’ve always struggled a bit getting a spoon/bowl knife “really” sharp. You know, wicked sharp, where it wants to cut the wood from across the room? I’ve taught loads of people to sharpen chisels, plane blades,…, but these were all tools with a cutting edge along a straight surface. As you well know, the spoon/bowl knives have their cutting edge along a curve, which is what makes them more difficult to bring to the highest level of sharpness.
A while ago I recalled how I’d made two accessories that fit a small, tight-radiused gouge, and helped me hone it effectively. So why not use a similar process for these curved knives?
I found a scrap of Pine (I like using a softwood, but you can use what you have available) that I cut into two blanks that were about 4″ long and 1 1/2″ – 2″ wide. This allowed some extra material so I could hold it safely, while I was honing the knife. On the first, I used my spoon knife (made by John Switzer @BlackBearForge on IG) to remove some wood along a portion of one face, until I had a recess that matched the curve of my knife. This was just a shallow recess, just so no one works hard trying to fit the whole of the curved blade down into it. On the second pine blank’s end, I pressed a section of the curved knife’s blade into the end-grain, and then removed wood until I reached the cut line (curved).
As you can imagine, both blanks were made to these shapes so I could apply some honing compound, and then hone the blade against them. Having the blanks/jigs matching the shape of the knife creates a wider contact area, rather than just a point, which for me helps stabilize the knife and “jig”. When I’d used a flat piece of wood (with some honing compound on it) to work the outside of the spoon knife, I could tell I wasn’t as consistent.
You can use whatever honing compound you’d like, or if you are needing to sharpen, rather than hone, you can apply a section of PSA sandpaper to the “jigs” internal / external curves. I like to use the Tormek honing paste on the “jigs”, that my Tormek T-7 came with years ago, as it seems to cut most metal quickly as well as bring to a very polished surface. You can pick up a tube at Highland Woodworking (a link to their website is over on the right side of my page, and full disclosure, I do get compensated if you purchase through that link) or a number of other retailers.
Here is a quick video I made to show how I am using the “jigs” I discuss above, but if you cannot view this, the direct link for Youtube is here (or you can copy and paste this info: https://youtu.be/qOlaTIEUAVM ).
I hope this makes it easier for each of you to make your spoon knife as wickedly sharp as possible.