Differences in sharpening methods.

T. Erdelyi

T. Erdelyi

Joined
Feb 3, 2001
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I've been freehand sharpening for nearly 30 years, and like most when I started I sucked. I don't think anyone was born with a bandaged thumb,(get it, kinda like a green thumb:)). Anyway the point I'm trying to make is that, ever since I've been sharpening by hand I've always been taught that if you have to push hard to put and edge on your knife than you've been using the wrong grit stone.

It's very difficult to maintain a consistent angle when applying so much pressure, also you have more chance for an accident when applying so much force.

Now I've been taught old school by butchers and hunters/outdoorsman how to sharpen, I rate myself pretty high on the ability chart, but I keep seeing threads where people are being told that they are not applying enough pressure when they sharpen.

I've been told by many experts :rolleyes: that if you have to work so hard to get a good edge your probaly using the wrong stones,(didn't I say that already?)

My question to you experts is: Is pushing harder the way to achieve the edge you desire or is a lighter pressure with a more aggresive stone the way to go?

Much like there is no one knife, that does it all, there is also not one stone, that does it all.

You always sacrifice something when you try to find one tool to do it all.

I'm lookin' for feedback.
 
There is nothing magical about using a coarser grit that lets it remove material without pressure. You gain some advantage because you are not wasting energy reducing the removed material to as fine a powder as when a using a finer abrasive, but I see much of the advantage in reduced heat generation. You usually use a coarser grit because you want to remove a lot of material in a moderate amount of time. It generally takes pressure to achieve the faster cut rate. I tend to use higher pressure and a coarser grit when I have a lot of material to remove.

In the case where you have a limited choice of grit (such as a Sharpmaker with only a couple rod varieties) your only choices are: use the rod edges (which gives you higher pounds per square inch of pressure) for a deeper cut and use higher force against the rods. I have a lot of alternate abrasives so I can usually get around this. In days gone by I would have used the edge of a medium-coarse aluminum oxide bench hone and high pressure to speed up the job. Now I use an 80 grit sanding belt. If I am sharpening a really heavy blade I will use high pressure even on an 80 grit belt.
 
When I work freehand, I run about 1kg of pressure, up until my final strokes on each stone(and my final stone at about 1/2kg and then the blade weight alone).

Was taught by my grandfather, just a quick lesson and then let loose. Still evolving in my skill level, but I can shave off the 800 benchstone(alumina oxide whetstone that I use dry), and the 500 is getting there.
 
In regards to using the sharpmaker. I took my lead from Sal Glesser's video. He says to use enough pressure on the hones so that you can feel the hone "bite" into the blade. Basically moderate pressure with the knife in the sabre grip. Then ease up on the pressure as you go to finer hones & finish the blade.
I use less pressure when using the EdgePro because there is more of a mechanical advantage with that tool & it works well without a lot of pressure.
As you point out, too much pressure makes it hard to control the angle.
P.S.
I'm no expert, just a student. But that's how I sharpen.
 
Jeff Clark :

I tend to use higher pressure and a coarser grit when I have a lot of material to remove.
Click to expand...

Yes, unless you are using diamond plates, when you are shaping an edge you go as heavy as possible. When you are sharpening however you want to minimize the force necessary to keep the edge deformation light. This means use the sharpest hone possible on a wide surface.

-Cliff
 
Stones go from coarse to fine, and pressure can be heavy to light. With something liek a waterstone, it is advantageous to go with good pressure at first and then ease up on the pressure. Then, you're using the slurry to do the work, and the slurry is of a higher grit than the actual stone, so you kin-of have 2 stones in 1! For the most part though, as said I don't use too much pressure unless I am using a coarse (non-diamond) stone. I did use a lot of pressure on my 400 grit stone when I sharpened my MEUK the other day, and the edge was less than stellar, so maybe I need to ease up!
 
I probably press harder than I need to. It's funny I never thought about it before but in all of the woodworking I've done, the mantra "let the tool do the work" is really good advice. In most cases, forcing the tool harder into the work doesn't get you there any faster and you're definitely working harder. I'll have to try the lighter touch and see if that changes how my sharpening ends up.

Rob
 
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