a better way to cut the grass
 

apparently fruit trees don't like having the grass cut around them to much, something about a symbiatic relationship with the grass, and fungi, and roots, so you are suposed to let it grow and only cut it a few times in the summer, starting after the tree starts to set fruit (baby fruits) so I pulled our Gravely walk behind tractor out of the shed, an ungainly beast of steal and iron with a 40" wide sickle bar mower, the sales brosure says it can run "up to 8 hours on two gallons of gasoline" not sure exactly how acurite that is, but it does run a long time on the little bit if gas I put in, but the best part of it is the mower, insted of being a woorling dull blade that just kind of hits the grass, the sickle bar mower is a row of shears that simply cut, very cleanly, anything up to the size of your thumb, and lets it fall over out of the way, insted of trying to spit it out of some silly little shoot after it's pulverized the clipings, and it doesn't care how long the grass is, 2 inches or 2 feet, it cuts the same.
Rotating shears, like old people powered push lawn mowers seem to make alot of sense as well, it would never be practical to spin a single blade that just swings at the grass, unless you had alot of energy to wast, like a gas engine, so I don't quite get why they don't make the rotory style shear cutters any more either, if you wanted to make an electric mower I would think that would be ideal just for it's efficentcy.

They still make people-powered reel mowers, plus they have ganged mowers for large-scale turf operations. They use them because they give a very even cut, more than you can get with rotary.

Before any of that, of course, were sickles. Although it was a single blade swinging at the grass, they were efficient since they were razor sharp. They had to work the edge every few swings.

I think rotary mowers are used mainly because they're so forgiving. Hit a rock with a reel mower and it's a serious repair job. Plus the blades are all covered up, which is a huge safety issue.

I just spent about 40 minutes sharpening my reel push mower for the first time - used for 2 summers before this one. (It should only take about 15 minutes to sharpen once you know what to do.)

And look out grass - what a difference. It's so much easier to push (not that it was too hard before), and it cuts much better, and it's even quieter than it used to be.

I tried sharpening it with a file before, but it's too hard keeping it square with the curved blades. So I bought a sharpening kit with some kind of grinding paste. Worked great.

I've had a number of people tell me just to use valve grinding grit, and run the mower backwords by hand to sharpen it, I have 3 of the things in the shed, and a 12 volt electric motor, and a old ZAP bike gel battery... as soon as I have more time I see a new project.

That's pretty much what I did. I've never seen valve grinding grit before, but I'm guessing that's what was in the kit I bought: a container of gritty blue gel, a brush to apply it, and a crank to spin the blades backward as per the instructions. You may also have to adjust the bottom bar against the blade as you hone the surfaces sharp again.