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The article is as follows:
Why sharpen tools? Most gardeners do not take extra time to clean and sharpen their tools mostly because either a. they don't understand importance of it or b. they don't know how. Hopefully this article will help you with both.
The main reason why it is important is that when a pruning tool, like a shear or a lopper, is sharp you get much cleaner cuts which is important to healing of tree or plant. Immediately after making a cut on a plant, it starts to ooze sap or resin. This is plant's natural protection remedy to provide a shield from weather, fungi and insects. When a plant has a jagged cut, as from an unsharp pruner, plant has a much harder time healing since there is a larger area exposed to all natural elements.
The second reason why it is important for sharp tools is that it will make your own efforts faster and significantly easier.
How to sharpen tools 1. The first step in sharpening any tool is to make sure blades are clean. I usually start by taking my pruning tool and cleaning blade with soap and water to remove dirt and debris. This step, however, will not get rid of sap and resin from your recent pruning. To remove sap you need to dip metal ends in a solvent such as kerosene. After I lightly dry them I give them a mild coat of pruner lubrication oil. This lubrication oil is not on a lubricant but will also prevent future rusting. If you are going to sharpen you tools at this time you can put lubrication oil on at end of that process.
2. The next step is determine correct sharpening angle. This is usually about 10 to 15 degrees. I then take my sharpening stone and put a light coating of vegetable oil on it to keep it lubricated. The oil not only keep stone lubricated but helps to carry away grit while you are sharpening. It is important to periodically to add a little more oil as your sharpen. To maintain correct angle, press blade against concave side of stone while sharpening. The main word of caution here is DON'T PRESS TO HARD! Use several smooth strokes, moving blade in one direction toward tip. For every 10 strokes to outer bevel, apply one stroke to inner angle.
3. To test whether you have sharpened blades enough you can perform light reflection test. Simply hold up newly sharpened blade to any light source. If you get a reflection off blade edge then you have not sharpened enough. It is important to note, however, that you don't want to sharpen blades too much as that will make them fragile. To do a final test you can go out and test sharpened tool on a size of branch is was designed to cut (i.e. cutting capacity 3/4"). If blades pull or catch you need to sharpen some more.