These knife sharpeners are cheap and easy to make. Using a layer of foam mouse pad underneath the sharpening surface allows the sharpener to conform to the curved shape of a convex blade grind. The mousepad could be omitted for non-convex grinds.
Cut a 1.5×0.5″ oak board into three lengths. First one is the length of the sharpener, two others slightly longer. I did mine nine inches.
Cut two strips from a mouse pad the size of the board.
Cut two strips of sandpaper as well. I use 600 grit and 1500 grit. Get your cement ready.
I used E6000 cement, works great. Glue the mouse pad down to the board, and the sandpaper on top.
Two sided sharpener. I mark one with a 6 since it gets a little hard to tell the difference.
Now it’s time to use those other two boards and clamp it overnight.
You can make a leather strop a similar way. I do those two sided as well. Between the strop and sharpener, this is all I use to keep all my blades shaving sharp. Fresh sandpaper can be simply glued on top as needed.