WARNING: Never sharpen or grind anything made of or containing aluminum or magnesium.
Because grinders can remove material rapidly, a freshly dressed wheel and the amount of work piece pressure applied to the wheel are keys to efficient grinding. Use the following basic guidelines to aid in working metals and avoid overheating:
•Never force the work piece against the grinding wheel.
•Always keep the work piece constantly moving against the grinding wheel with light pressure and even motion.
•Keep the work piece cool by maintaining a container of water nearby for dipping the work piece.
•Always use the face of the grinding wheel with the wheel moving downward, into the object being worked.
•Do not perform grinding operations on the side of the wheel.
Lawn Mower Blades
English
As you prepare to sharpen the lawn mower blade, ensure there is adequate working space to maneuver the blade. Lawn mower blades are generally sharpened on the beveled side and then dressed up slightly on the other side with the grinder or file.
First remove any nicks that may be present on the cutting edge by resting the blade flat on the tool rest, moving the blade side to side until the edge is nick free. To sharpen the bevel, either adjust the tool rest angle to match the blade’s bevel angle or hold the blade at the bevel angle while resting a portion of the blade on the tool rest for added stability. Use a light touch, removing as little metal as possible to attain the desired edge; then lightly
After the blade has been sharpened, be sure to check the blade’s balance with an appropriate shop made jig or commercially available unit. Balance the blade by progressively removing metal until balance is attained.
WARNING: An unbalanced lawn mower blade may cause excessive vibration, causing damage to the mower and engine shaft.
Sharpening Twist Drill Bits:
Sharpening twist drills can be a tricky operation that even some experienced mechanics never master. Sharpening twist bits freehand will require considerable practice and dry runs with the grinder "OFF" to acquire the skill of rotating the bit while maintaining the original cutting edge angle. If you anticipate sharpening numerous bits consider purchasing a specialized sharpening jig, available at most hardware and home centers. A typical technique for sharpening a twist drill bit is as follows:
1.Set the grooved tool rest horizontal to the face of the grinding wheel.
2.Hold the drill shank between the thumb and index finger, resting the back of the index finger on the tool rest.
3.Be sure that the cutting lip is straight across the face of the wheel before beginning each stroke
4.When the drill contacts the wheel, push the drill shank downward and to the left at a slight angle. At the same time, rotate the drill so the other lip is just visible.
5.Repeat this process on the other lip to sharpen the entire twist drill.
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