How to Sharpen Bypass Pruners
- 1). Clean the blades of substances that may clog your file. Use a rag dampened with sap and rust remover to lift rust, sap and dirt. Mineral oil also is effective at wiping off sap.
- 2). Examine your blades. It's important to maintain the right angle of the beveled edge of the pruner blades so they make the appropriate contact with the plant and each other. Only the outside edge of bypass pruners need to be sharpened. Check for nicks, chips and any other uneven spaces that may need to be filed down.
- 3). Sharpen your blades. A variety of whetstones and sharpeners work for pruner blades, but a diamond file is best for particularly hard metal. If you use a freehand file, make sure you are sharpening at an appropriate angle. A vice may be used to keep your pruners still as you sharpen. Some sharpeners are made specifically to hold your pruner and guide the file along its blades. Run the file along the beveled edge of the blade, not across it.
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