It is not difficult to sharpen certain Carbide cutting tools for small items like Chequering tools a set of Dimond needle files work well or you can now purchase a set of flat Dimond hone plates at a low cost these being very popular for woodworkers rather than oil stones, have used these for re sharpening Carbide router cutters very successfully. Though over the years I have found the larger the cutting edge it cam be rather tricky to re sharpen planer blades but not impossible to do by hand.

The only lessons in my life I truly did learn from where the ones I paid for!