Right Way to Sharpen Tools on Grinder - Chisel, Mini Bar, Screw Driver

Описание: Watch and follow the sparks. The sparks will tell you where and how the metal is being removed.
Sparks over the top mean the tip is being sharpened, and below the tool means removal of metal under the leading edge.
I hollow-grind tools on a bench top grinder. I prefer the hollow-ground bevel because it sharpens the leading edge, but still has enough metal supporting it.
Keep honing until you can feel a slight ridge of metal start to form all the way across the chisel’s back. This ‘wire edge’ indicates that the chisel’s end is sharp. Also, this indicates that the bevel has come to a point. Lap this edge off of the back of the tool.
Remember tools have 2 sides. Chisels and mini bars have a flat side. Making it flat is called lapping and only has to be only once to the full tool. After that, you just have to lap the first 2 inches usually.
The grinding heats the metal, and too much heat will kill the steel's temper, restricting its ability to hold an edge. If the edge starts to turn a blue color, it’s blued and you’re done. Then you have to keep grinding until all the soft, blued steel is removed.
You can prevent bluing by avoiding over heating. Reduce overheating by fewer passes, shorter time of passes, cleaning (dressing) the wheel, using a coarse wheel and dipping the edge in water occasionally.
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