Mower Blade Sharpening

When I sharpen a blade I do not grind the edge to the very end of the blade. I start at the inside edge of the cutting face and work quickly towards the outer corner {the rounded outer edge}. As you get to the outer corner, use much less pressure against the grinding wheel... and stop the grinding just as you get to curve of the rounded edge {continue the cutting/grinding stroke as if the corner WAS NOT rounded}. You do not have to follow the edge around the corner! As you progressively grind a few more strokes across the face, the rounded corner starts to take on a square look. Leaving a "slightly" rounded outer-edge has never caused me to leave a strip of unmowed grass.

As for the "balance" of the blade, just make the same number of grinding strokes on each face {striving to grind as hard or as lightly on each face}, whether both need it or not {grind the worst side first}. I have layed the blade across an edged tool or a narrow screwdriver shaft to quickly check the balance of some blades. You do not have to be "bubble-on" with mower blades {I have been using the same mower for 16 years and have not had to replace even one spindle bearing. I am on about my 10th set of blades for that mower too!}!

{p.s. Be sure to cool or dip the blade end immediately after EACH grinding pass. Don't even inspect the edge till you have quenched it!}

The first priority in changing blades is throw away any blade that has a crack in it. They are extremely dangerous.

Secondly once you've sharpened your blade so much that your cutting edge is getting close to where the blade curves up, toss them.

Thirdly, if at anytime you've lost half the thickness from your blade, toss them.

Lastly, if you have skipping, it takes lots of power to cut, or just cruddy mowing and sharpening doesn't fix it, toss them.

I usually buy my replacement blades when I am getting the cutting edge ground back to nearly the bent area of the back of the blade {approximately half the width of the blade}.

The reason it's important is 2 reasons. One it takes more power to cut the grass and secondly, it's will cause premature wear to your belts.

While both of these might not be noticable, they both happen.

If you use a weld to build up the cutting edge and grind it back sharp you can have a harder edge that last many times longer.