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The forum title says "share success" so I have some advice and examples that I'll throw out there and a few questions as well. Don't give up, not on time spent, your technique or even your choice of sharpening medium. You may be doing something right and throwing in the towel before you get the result you want or need. I started out by going for a Totin' Chip badge as a boy scout, had to re sharpen my chisels often as a carpenter and learned a lot about the need for stropping in Barbering school. I'm not the best but I have enough to experience to share a view. If you are new, don't rush to buy an expensive stone, it's easy to ruin a stone but also easy to get discouraged if you don't use it right. If all you have is a cheap stone, just apply some honing fluid, hold the angle you like and make circular motions over it until your bored and then do it for another 10-20 minutes after that. Switch directions periodically through and you'll have a cutting edge no matter what the grit. How long it will hold that edge really comes down to what you are cutting and how often you hone it. I've seen friends use a cement block for the rough work and switch to red brick for the finish and it still cut fine. Some stones don't like honing fluid, some prefer water, some can be used dry but if it's a wet stone and you don't keep the particles that come off of the blade flowing away from the stone it will ruin the stone so even if it's a cheap one or a "hand me down," know your stone. Intermediate, if you have a decent grasp of it now you can start using multiple mediums and move on to honing. One rough and one finish is fine to start but it will take a fair amount of time and effort if you jump from a low number to a high number in one session. Here you can move past circular motions and start using even strokes like you are trying to slice a thin layer of cheese while choosing a specific angle for a specific use. Some people use 10 swipes in one direction, then flip the blade and do 10 swipes in the opposing direction for the opposite side of the blade. Some people alternate for every swipe. Again, don't give up if it seems like it's not working it may just need more passes, especially depending on the steel used. Which brings me to steel. I don't really care for most stainless steel. It sharpens quickly and dulls even faster. On top of that, most stainless steel can not hold a razor edge for more than one cut through any medium or material. I say this because I shave with a straight edge razor and no matter how sharp a stainless straight edge feels it may shave hair off the back of your hand but it will not go through course beard hair. (We may be talking about leather work here but this is my best example of what sharp is.) High carbon steel is what I use for my chisels, kitchen knives and all my leather work blades. The key to keeping blades happy is honing. Some just call it "stropping" because a strop is used to hone a blade but you can hone on a kitchen steel or even the back of another knife. Honing is the straightening of the blades edge. As you cut and even as you sharpen the blades micro edge will curl. Longer blades will even wave in and out of alignment. Honing brings the blade back to where it should be. I hone on a strip of leather glued to a piece of hardwood, aka a paddle strop. I use backwards, even strokes pulling away from the blades edge. How often? Depends, eventually you can feel when it needs to be honed vs needs to be re-sharpened. Advanced, this is where you tell me. I have a few pointers and that's about it for advanced. Don't over sharpen, yes it happens. The blade will curl or chip depending on the metal. If it doesn't curl or chip and is over sharpened it will be very hard to control. It will slice so smoothly that you won't realize the blade is slipping past the surface you intend to skive, shave or cut until it's too late. Find quality metal, I tend to only use high carbon but I know someone will say they have razor sharp blades in stainless steel. If you do, please share the type of steel. My current sheath project is for a skinning blade made of 1095 folded with 15N20 and you can bet your socks I had to look up what 15N20 is so share your thoughts on steel. Also, what medium do you cut on and how do you store your blades. Durable mats and boards usually dull blades too fast and flimsy mats save your edge but fall apart too soon. Any decent middle ground? Storage, best ways to store blades so that they don't smash off of other tools and stay dry so they don't rust?
The Edge. The business end of a knife or cutting tool. The perfect edge occurs at the intersection of two planes, which are the sides of the knife that intersect each other; the perfect edge formed by the two planes would a one dimensional line of zero radius. This is just not attainable, because the planes are made of something whose molecule has a radius, and where they intersect an edge is formed by at least a single molecule that has a radius. In practical terms, this ain't a going to happen. Maybe in a lab, maybe. But there is a downside, it is a fragile edge that won't hold up and will round over to the point that it is less sharp but more durable. That is the scientific claptrap. Our best edge is going to be rounded to the point that you and I can see it with a loupe. I have four loupes, a 5x, a 10x, a 20x, and a 30x, and some comparator scopes that go way beyond that. If I take a brand new Irwin Utility knife blade out of the box and look at the edge under 5x, I can see the edge. At 10x the edge is obvious, and a 30x it looks like a landing strip. Quality scalpels are somewhat better, but still a highway at 30x. Quality of the plane grinds (facets, bevels) and polish are an important in attaining a small radius, but included angle of the edge (plane 1 degrees from centerline + plane 2 degrees from centerline) is as important a factor. The size of the radius will increase with the size of the included angle. Unfortunately, the durability (how much strength or metal is behind the edge) decreases with the decrease in included angle. We are always fighting the metal to get the best balance between edge radius and durability. Utility knives, razors, scalpel,s and anything of that ilk sacrifice durability for sharpness. Sharpen often or put in a new disposable blade. So edge angles are going to be minimal, but these things will really cut; for a while. So what is the proper angle for a knife edge? I feel a range of 20° to 50° is about right, but covers a lot of territory. I guess some examples might be appropriate. Bench Knife or skiver -- 20° to 25°, maybe even 30° Shoe Utility Knife -- 25° to 30° Pocket Knife -- 25° to 30° Kitchen Knife -- 25° to 35° Head Knife -- 20° to 25° Wood Chisel -- 25° to 35° depending on use Planer Blade -- 40° Axe -- 40° to 50° Lawnmower Blade -- 90° or a bit less Art
This thread is sort of my knifemaking/sharpening blog. I make the occasional knife, most of them tactical ones for friends kids and grandkids who are just graduating from basic or advanced training. I mostly sharpen scissors (from standard to technical stylist scissors/shears, to a pair of Fiskars), knives, hand and power tools, leatherworking tools, most garden tools (please don't bring a 1,000 lb garden tractor over here with the mower blades attached), Dog and human hair clippers and blades (sharpening and repair), I'll tackle most anything if you are in a bind, but I will send out saw blades and end mills as there are others who can do them better. That being said, I am retired. I don't have to do anything If I don't want to, I do it just to do something that I know how to do. We all like to feel useful, but I ain't going to work myself to death. This is kind of the see something, say something of a knife shop. Everyone is welcome to add to or ask questions. Art