I know that keeping your blades sharp means the mower works much better鬥・asier, thereby using less gas and so does less polluting.
I've been reading up on the sharpening process. All the experts I've read say not to use a grinder because it heats the blade up and that makes it hard, and destroys it. They then confuse me by saying use a bench grinder.
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So you've determined as I have that some of these people that write articles are really X-Perts and not experts.
A bench grinder or any type of abrasive can be used as long as the temperature is held below about 450ーF (232ーC). This is one reason a file is often recommended. Not even
Sling Blade could file fast enough to heat a blade that hot. In my opinion a blade that can be readily filed with ease isn't much of a blade, but a blade approaching the hardness of a cold chisel has merit.
To sharpen mine, I set in a comfortable chair with the blade across my leg using a right angle grinder. Light pressure, continual movement of the grinder, watching for discoloration and being able to see the angle being ground contributes to success.
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If you want to study an old school steel hardening process, the link below is written so people less than enjinerrs can understand. I used these methods as a kid making chisels and punches.
A Woodworker's Guide to Tool Steel and Heat Treating