So, I have been writing this out. I got all the way down to number 6 before it hit me… Paul Sellers! He is a world-class woodworker and has a YT channel loaded with useful information about maintaining the cutting edges of his many planes, routers, handsaws, and chisels. That would be my number one recommendation…
First, I always recommend “non-powered” methods. I love my DMT plates and Japanese Wet Stones. I use a variety of methods though, depending on what I am sharpening. Chainsaw blades, for instance; I will use a guide and file if I am just doing 1 or 2 chains. If I need to sharpen several at a time and on a regular basis, I like using my Oregon Chainsaw Grinder.
I prefer a bench grinder for sharpening those chisels and drifts used in Air Hammers or Jackhammers. I have spent weeks at a time sharpening buckets (literally… 5 gal buckets filled with used jackhammer chisels) on the bench grinder.
I have a slow RPM Tormek wet stone grinder that I haven’t touched in years but used to sharpen all of my kitchen knives on. Today, however, when it comes to pocket knives and kitchen cutlery, I wouldn’t go near a grinder of any kind (even a slow-rolling wet stone) There are a few basic tips to keep in mind when sharpening a knife.
Always draw the blade backward away from its edge.
As a kid, I was taught the wrong way to sharpen my pocket knife. I was told to push the blade down and forward toward the cutting edge… Nope! The goal is to remove just enough material to form a new cutting edge. This means pulling the blade away from its edge so it can form a “Burr”.
Don’t roll the blade as you are pulling it.
Keep your wrist locked and watch the space between the spine or the top of the knife blade and the stone. Keep the space consistent to get a flat, consistent bevel. Allowing the gap to increase as you pull the blade toward you will result in a rounded bevel. One trick I use is to place my thumb on the back of the knife and keep the side of my thumb just barely grazing the top of the stone surface. If I keep my finger in the same place on the blade and barely touch the stone as I draw the blade toward me, I get a consistent cutting edge no matter how many times I need to do it.
There is no big mystery to sharpening a blade.
I know some of these guys act like they are unlocking and revealing hidden secrets of the universe. Your goal is to get a nice long even burr formed along the edge of the blade that you will eventually remove with a strop. Also, know that there are many times where all a blade needs is a good stropping to get its edge back. Once I sharpen a knife or chisel, It will likely never touch another stone. I keep my blades sharp with a leather strop and either green or white compound. My french skiving knife that I use on nearly every single LW project gets stropped with green compound before it ever touches leather.
Try to get the entire length of the blade in a single draw to maintain a consistent edge.
For longer blades like a chef’s knife, you will need to draw across the stone as you are pulling it back to remove material from the entire length of the blade. I know this sounds counter-intuitive but as long as you are drawing the blade away from its cutting edge, and maintaining a consistent gap (not rolling the edge), you will begin to remove material and start forming a new edge.
Switch sides with each stroke.
Another mistake I was taught as a kid is to sharpen one side then the other and eventually, the two sides will meet and form a sharp edge. When you are trying to get the sharpest possible knife, the last thing you want to do is offset your edge by grinding away too much material from one side before you flip the blade over. THIS ONLY APPLIES TO A DOUBLE BEVEL BLADE!.
If you are sharpening a single beveled blade, then repeated passes over the stone is exactly what you want to do.
The burr does not show up right away.
As you remove material it will slowly begin to form at the edge. With my DMT stones or even my Japanese Stones, I am usually on to the second stone before the burr becomes really prominent. If we know that a consistent edge requires keeping the blade at a set angle all the way through the stroke (ie: not rolling the edge) and we know that to get the burr to form, we need to draw the blade away from its edge, then the formation of the burr will help us judge the progress of the blade. This only comes with experience. The burr will tell you everything you need to know.
Do not be afraid of scratching the beveled edge. I knew a guy at one time who would not sharpen a knife because he was afraid of scratching the polished edge. It took me showing him the entire process for him to realize that in sharpening the blade and stropping to remove the burr, we actually re-polish the edge and leave it looking brand new. If you use the “Thumb” technique I mentioned above, you won’t have to worry about scratching the sides of the blade, just the cutting edge.
Much of this has been about sharpening knives. As Leatherworkers, we work with many cutting tools that only have a single bevel to them. Japanese Skiving Knives, French Skivers, Edge Bevelers, Groovers, etc… These are just simple variations of the woodworker’s chisels and planes. As I mentioned above, Paul Sellers is a fantastic resource for learning to properly sharpen our tools.
I will stop here for now and see if there are any questions I can answer.