Today’s sharpening

Today, I worked on re-sharpening a Blue #1 MizuHonyaki Fuguhiki.
Even though I call it a re-sharpening, it was really just fixing the edge by correcting the bite.
Blue #1 steel tends to become a bit round-edged and soft because of its hard and tough nature, making it prone to dullness. I started with a diamond stone, but the stone and the knife were at odds, so I couldn’t get the edge as I wanted!
The reason the diamond stone didn’t work well, I think, is because of the stone clogging up and the hardness of the diamond surface. When you’re working with hard steel against hard diamonds, it’s a bit slippery, and the tough steel particles clogging up the stone surface just make it worse.
So, I had to switch to a regular coarse stone—‘Ato-kun,’ the kind that chips off in flakes.
A medium stone could have worked too, but rather than gently working on it with the finer stone, I prefer to take a more aggressive approach with a stone that has better cutting power, just going at it all at once for a cleaner result. By the way, I had to flatten the stone three times.
As expected, this method allowed me to quickly get the base sharpening done better than with the diamond stone.
There were some minor chips scattered across the edge, and since the request was for a flat grind, I focused on making sure to establish a nice convex edge.
For the back, I used a #1000 diamond stone, carefully removing the clogging while working on the grind.
The Uraoshi, which only makes contact with the back and the tip of the knife, didn’t clog as much as I thought it might.
With the convex edge done right, I noticed the burrs were sharp and snapping off cleanly.
Now, the challenge is deciding what kind of finishing polish to do next.
At this point, the edge is really aggressive, almost like a 1-to-1 relationship between the movement and the cutting action—it’s biting really hard.
The next step is how smooth I want to make it. A slight polish with a Suita stone might create a better balance. However, since I believe the customer will finish the sharpening, I’m thinking of stopping at about a 1-to-3 ratio with this sharpening.

• 2015-03-11