Wednesday, May 24, 2017

Lawn mower sharpening on your metal lathe

2 comments:

Anonymous said...

Hmmm. I'd like to see it done.

Illustration '3' looks amiss to me. It looks like the body of the motor will collide with the mower reel once the grinding wheel has gotten only part way along the reel.

Illustration '6' looks like 100% thought experiment. Consider: "It is best either to gear down the motor or provide a resistance in the circuit so that it rotates about a hundred or so revolutions a minute."

As far as I know, slowing down an induction motor by introducing a series resistance to its voltage supply is a fallacious, utterly unsound practice. As I may have said before, much of how-to 'literature' is hallucinatory hogwash.

Hand-pushed reel mowers are why Tecumseh and Briggs & Stratton and rotary mowers were invented.

The Duke said...

Good points. I love your phrase "hallucinatory hogwash"! I posted the article simply because it harkened back to a day when small metal lathes were much more commonplace. Given that grinding on a lathe, without protecting the ways first, deposits abrasive grit dust where it shouldn't go, using a lathe to sharpen lawn mower blades is an abuse of the machine tool. And, yes, reel lawnmowers might be mechanically fascinating, but no one wants to cut grass with them anymore.