10-22-2017, 03:27 PM
(This post was last modified: 10-22-2017, 05:50 PM by Mark Reich.)
Gees. I feel kinda silly for not thinking of this sooner. By far, the most common single bevel edges are... Scissors! Everyone has lots of single bevels right under their noses!
For the stickler, I use the words "scissors" and "shears" interchangeably simply because almost everyone does. Hair cutting scissors are most often erroneously called "hair shears", so that alone totally skews the field. At any rate, I don't mean to make any distinction. I guess "shear" is easier to spell than "scissor", and most people probably think "shear" sounds more professional than "scissor".
Hair scissors can be very expensive, and sharpeners usually get $20-$30 per scissor, which makes them one of the most lucrative items to sharpen. Hair cutters know absolutely nothing about sharpening, but they sure can tell if their scissors are less than perfectly sharp within about two snips.
Once upon a time, I wanted to be a professional sharpener. Miraculously, I ran into Mr Rupert, the man who would prove to have the greatest influence on all of my sharpening related items of interest. With a lot of Mr Rupert's help and guidance, I traveled thousands of miles to learn to sharpen hair scissors from the likes of Bob Crilly, and learn firsthand from several more successful, dedicated sharpeners.
It's almost a secret that professional scissor sharpeners never touch the flat side of the scissor. They know how important it is to keep the flat side "factory flat" for the life of the tool. They "deburr" (I would say "distress") on a popsicle stick or whatever.
Now, case in point. A Master Gardener friend brought her manual hedge trimming shear in for a sharpening yesterday. It was a well used tool, but it had been pretty carefully maintained with a file. It wouldn't cut anything Cleanly though, because the flat was not flat all the way to the edge.
I made a single, slow pass with a used 60 grit belt to reprofile the bevels. I needed to remove enough of the edge to get rid of the "unflat", which means I needed to grind the bevel back a full 1/16". I ground the bevel edge leading on the vertical platen, with the flat facing me, so I could see when the edge was ground back to the flat plane.
This produced a pretty big burr on the flat side of the blades. If one is very careful about placing the flat on a flat stone, it is possible to remove the burr while maintaining the flat. I used an Atoma 400, so it took less than 10 seconds to deburr both blades. I pronounced them "sharp", stepped out onto the lawn, and tried them on grass. Wow! They cut beautifully, especially for a 90 second sharpening job. I thought I better make the most of it.
Just for fun, I told the Master Gardener that only a master sharpener could make hedge trimmers sharp enough for a haircut, to which she heartily agreed. I got my hank of human hair, and made several snips along the whole length of the blades. I might as well have had a $1000 pair of Japanese hair shears. Honestly.
I have to admit this was a good showing of a fresh edge, but pretty typical for any single bevel. With decent carbon steel and good stones or plates of medium grit, there is no deburring. That's my definition of efficient.
Many Japanese blades take it a step further by hollow grinding whenever they can, so keeping a flat side flat is easier.
For the stickler, I use the words "scissors" and "shears" interchangeably simply because almost everyone does. Hair cutting scissors are most often erroneously called "hair shears", so that alone totally skews the field. At any rate, I don't mean to make any distinction. I guess "shear" is easier to spell than "scissor", and most people probably think "shear" sounds more professional than "scissor".
Hair scissors can be very expensive, and sharpeners usually get $20-$30 per scissor, which makes them one of the most lucrative items to sharpen. Hair cutters know absolutely nothing about sharpening, but they sure can tell if their scissors are less than perfectly sharp within about two snips.
Once upon a time, I wanted to be a professional sharpener. Miraculously, I ran into Mr Rupert, the man who would prove to have the greatest influence on all of my sharpening related items of interest. With a lot of Mr Rupert's help and guidance, I traveled thousands of miles to learn to sharpen hair scissors from the likes of Bob Crilly, and learn firsthand from several more successful, dedicated sharpeners.
It's almost a secret that professional scissor sharpeners never touch the flat side of the scissor. They know how important it is to keep the flat side "factory flat" for the life of the tool. They "deburr" (I would say "distress") on a popsicle stick or whatever.
Now, case in point. A Master Gardener friend brought her manual hedge trimming shear in for a sharpening yesterday. It was a well used tool, but it had been pretty carefully maintained with a file. It wouldn't cut anything Cleanly though, because the flat was not flat all the way to the edge.
I made a single, slow pass with a used 60 grit belt to reprofile the bevels. I needed to remove enough of the edge to get rid of the "unflat", which means I needed to grind the bevel back a full 1/16". I ground the bevel edge leading on the vertical platen, with the flat facing me, so I could see when the edge was ground back to the flat plane.
This produced a pretty big burr on the flat side of the blades. If one is very careful about placing the flat on a flat stone, it is possible to remove the burr while maintaining the flat. I used an Atoma 400, so it took less than 10 seconds to deburr both blades. I pronounced them "sharp", stepped out onto the lawn, and tried them on grass. Wow! They cut beautifully, especially for a 90 second sharpening job. I thought I better make the most of it.
Just for fun, I told the Master Gardener that only a master sharpener could make hedge trimmers sharp enough for a haircut, to which she heartily agreed. I got my hank of human hair, and made several snips along the whole length of the blades. I might as well have had a $1000 pair of Japanese hair shears. Honestly.
I have to admit this was a good showing of a fresh edge, but pretty typical for any single bevel. With decent carbon steel and good stones or plates of medium grit, there is no deburring. That's my definition of efficient.
Many Japanese blades take it a step further by hollow grinding whenever they can, so keeping a flat side flat is easier.
A post or two later he follows with a humorous anecdote about a salon experience. 