Alo,
I was glad to see the sharpening gadget had ceramic rods, too. I don't trust carbide scrapers to make a knife-edge and wondered if they left a stretched or torn burr on an edge. When I used them, the resulting finish was odd.
I like "diamond" bench stones, and mostly sharpen edges with them, often using a clamp-on gadget to hold the blade at a fixed angle.
I have one gadget similar to yours, but where tiny strips of flat diamond-on-nickle are held at a fixed angle so you can saw a dull edge back and forth. Even then, I'll only use "back and forth" sharpening to set a coarse bevel.
Sharpening "perpendicular to the edge" seems to me to give a better final edge - but what's best for a knife might not be best for a weeding tool. And I know someone who sharpens a machete "lengthwise" ... in fact does it with a file, not a stone. And gets a good edge.
But I do use a crossed ceramic rod handheld gadget for "steeling" between sharpenings. I think it mostly straightens the edge, while also removing a tiny amount of steel. I also think of it as "polishing" or burnishing a micro-bevel.
Corey
