Sharpening: The Lies of the Eyes
Isshi Yamada never said much to me when I was dating his daughter in college. To us Western students who studied Eastern religions, he was an enigmatic Zen Buddhism professor who was famous for giving exams that bordered on the surreal.
Most of my memories of Dr. Yamada put him sitting at his dining room table in a worn Irish fisherman’s sweater , drinking a little sake and watching the affairs of the household.
One day, however, Dr. Yamada became quite animated on the topic of human perception. And his short lecture sticks with me to this day.
“What is the one thing the eye cannot see?” Dr. Yamada asked.
Dr. Yamada shook his head.
“What is the one thing that fire cannot burn?” he asked.
Like most Westerners, I started to go literal. “Titanium?” I said (or something equally stupid).
“What is the one thing that the finger cannot touch?” he asked.
I shook my head.
“The eye cannot see the eye. The fire cannot burn the fire. The finger cannot touch the finger,” he said.
This short condemnation of self-analysis and self-perception has colored my thoughts every moment since that day. Including today.
As I’ve said before, I do a lot of sharpening. I sharpen things almost every day. I think nothing of the process. I don’t obsess about it. I don’t blog much about it (there is no “Sharpening” category for this blog). For me it is like religion. Not the fervent kind with snakes and faith-healing and fried chicken. The kind that simply flows through everything. Without it, things wouldn’t exist. Without sharpening, woodworking wouldn’t exist. Period.
And I don’t talk about sharpening much on this blog because people get upset. And you should never ever get upset about sharpening. That spoils your efforts.
I have a theory. Maybe it’s more accurate to say I had one. Here it goes:
When I sharpen with waterstones, I get the best results if I use firm pressure when beginning with a new grit then I use gradually decreasing pressure on that new grit. This change in downward pressure seems to speed the polishing process, or at the very least it polishes the areas around the deeper scratches, revealing them to my blind eyes.
My crackpot theory: The firm pressure breaks up the waterstone and those particles get smashed into smaller particles on the surface. The lighter pressure I use at the end of a grit allows those smaller particles a chance to work the steel.
Bottom line: Using less pressure will speed your efforts.
So I sent my theory to Ron Hock, the founder of Hock Tools and the author of one of the books we publish that I am most proud of, “The Perfect Edge.” Ron (or the Rev. Ron as he is sometimes called), thought about it for a bit and replied:
“I think mine is the simpler theory so, according to the principal of Occam’s Razor, I’m right. (But I think you’re right, too: That due to the crushing action you are loading the surface with finer and finer grit grains and reducing the pressure allows the blade to float on them.)”
So that’s the set-up , not the real story. I have spent the last 17 years of my life sharpening and dulling steel edges, and that is my honest perception. When I use firm pressure I can get my edges only so polished. Then they stop looking better , no matter how much I work. But if I start using lighter pressure, they look better on that same grit.
So I set out on Monday to show this through photographs using our nice macro lens. I sharpened an A2 iron on my #1,000-grit stone until it stopped improving using firm downward pressure. I took its photo. Then I switched to delicate pressure on the same grit. It looked a lot more polished. I took its picture using the exact same camera position, iron position, light position and camera settings.
– Who makes the best honing guide for chisels? Richard Kell. End of story. Buy them direct from Richard here. (And buy a sundial while you are at it.)