The ability to cut your lawn boils down to a very important factor, how sharp is your rotary mower blades? The Briggs engine that powers your most excellent yard management tool can do so much for the beautification of that little piece of heaven, your turf. That is true and it is also true that you need a very sharp system of blades in order to make a clean cut as well as keep the yard looking its very best!
Since there is no big technical mystery to sharpening a lawnmower blade we will not bore you with the specifics involving how to hold or what tools are needed in order to do the job properly. Well, maybe we will say that it will require common sense and a bit of know-how as well as a good bench grinder or a professional blade grinder. But that is all we are going to hark on about that subject.
1. Remove the Blade
The very first step of the blade sharpening job can sometimes be the hardest part of the job. A good way to start is to squirt some penetrating oil on the blade bolt and nut and let it stand for a few minutes. That should loosen thing up enough for you to get busy. Please recall that you need to pull the spark plug wire to make sure the mower does not accidentally start. We have all seen those good-minded individuals that had stitches in their hands or even a few missing fingers because the engine fired unexpectedly. Secondly make sure that you block the blade so that it does not turn while you are removing the blade nut. A blade holder will make this easy. However, if you do not have one, a block of wood under the deck and a C-clamp will do the job. Once the blade is removed, use a scraper to remove excess grass build up around the center hole of the blade. This will ensure a good, tight fit and assists in keeping the mounting bolt from working loose.
2. Sharpen the Blade
Now that you have removed the blade, it’s time for sharpening. The primary goal is to consistently maintain the correct angle on the blade. Manufacturers perform hours of testing to determine the angle that will give the user the best cut with the longest span of time between sharpening. It’s important to keep the angle as it was intended. Around 40 degrees is typical, but this can vary, so check with the blade manufacturer to obtain the exact figure. As you sharpen, move the blade back and forth across the grinder, maintaining the proper angle until you get the edge you need.
3. Balance and Straightness
It is not necessary to grind a blade until all nicks are out. That will only lessen the life of the blade entirely. Grind until you have a sharp edge on the blade in the area where there are no nicks. A blade with numerous nicks should be replaced, but a few can be tolerated.
4. Remount the Blade
Once you have finished balancing the blade and checking it for straightness, clean any burrs or jagged edges with a metal file. Now it’s time to put the blade back on the mower deck. Remember you now have a very sharp blade. Use extreme caution when installing.
There you go! You are now a proud owner of a very sharp and ready to rock lawn mower rotary blade! Your Briggs engine will appreciate the effort you have demonstrated in making its job that much easier!