Reel lawn mowers are environmentally friendly. They don't burn gasoline, which means they have no emissions. Their power is supplied entirely by you pushing it. As with any type of lawn mower, eventually the blades will become dull and need to be sharpened. Unlike gas-powered mowers, which have a rapidly spinning blade that strikes the grass blade to cut it, reel mowers cut the grass like a scissors cuts things--the grass is pinched between two blades and sheared off. It is fairly easy for the average homeowner to sharpen a reel push mower.
Purchase a reel mower blade sharpening kit. These can be found at your local hardware store or online.
Prop up the reel mower so that you can turn the blades with the wheels by hand. If the handle gets in the way you can remove it from the reel mower easily by unfastening a few bolts.
Remove the plastic cover on the side of the wheel. It can be popped off with a screwdriver. Use a screwdriver and remove the "C" ring that holds the wheel in place.
Remove the wheel and set aside. Inside you will see a gear that turns the blades when the wheel spins. Remove this by pulling it off.
Open up the sharpening compound container and gently apply it to all the blades on the reel mower. It's easiest to apply it with a paint brush.
Take the crank that came with the sharpening kit and place it over where the gear was attached. Turn the crank so that the blade spins backwards. Keep turning the crank until you see a smooth metal edge on all the blades.
Remove the crank. Place the gear back on the gear shaft. Place the wheel back on and put the "C" ring back into place. Pop the plastic cover back on to the wheel.
Bolt the handle back on if you removed it. Your reel mower should now be sharp and ready to cut the grass easily.