Keep Your Mower Blade Sharp

Step 8: Grinding--part 2

When the upper part of the blade looks good on both ends, turn it over and grind a little on the underside. A couple of passes should do the job.

How often should you sharpen the blade? A lot depends on how much mowing you do each week and if your mower picks up small rocks while mowing. If your lawn is not large and the mower does not kick up small rocks, once a season should be enough. If you keep your blade fairly sharp, it does not take long at all to touch it up a little when it begins to dull.

Comments

[fridgewrestler]

Why go through the trouble? A file is faster (considering setup) and does a better job putting an edge on the blade.

[Phil B]

It is really very, very little trouble. I have always found files slow.

[graydog111]

I agree, Phil B. Thanks for posting this. I mow 15 acres with a 60 inch ZTR mower and your method will work very well for me. I must sharpen my blades at least 6 times per season, so I have 6 sets (18 blades) and sharpen several sets at a time so they will be ready when I need them. If I let the blades get too worn before sharpening, they require too much grinding to be practical. Use a file? Forget it. I do have a Sears radial arm saw and I will try it.

[Phil B]

Thank you for looking. Let me know how it works for you.

[billdan]

Thanks for the tip. I have never seen a jig for a lawnmower blade and always used an angle grinder and this is a great way to get more use out of the saw.

[Phil B]

In addition to the things I listed in my first response to your comment, take a look at how to use your radial arm saw in place of a joiner. See: http://www.instructables.com/id/Joint_Boards_without_a_Jointer_1/ (if you do any furniture making).

[Phil B]

Thanks for your comment. A radial arm saw offers a lot of versatility at a much lower price than a Shopsmith and takes very little space. If you have a Sears Craftsman radial arm saw, you may be interested in an Instructable I did to compensate for wear in some of the yoke's indexing holes. See: http://www.instructables.com/id/Sears_Radial_Arm_Saw_Egg_haped_Indexing_Holes/ If you have a Sawsmith radial arm saw, you will be interested in another Instructable I did. See: http://www.instructables.com/id/Sawsmith_Radial_Arm_Saw_Enlarge_Arbor_Hole_on_a/

I have in mind to do two or three more Instructables related to radial arm saws. Apparently they have lost popularity to compound miter boxes. Still, there are a lot of them around waiting for someone to use them right.

[billdan]

I also have a power miter and it is great since it is very portable but it is only capable of cutting angles and is limited to narrow lumber as it was designed. The radial arm saw is much more versatile in that it can cut angles in 24" width stock and I have ripped 4X8 sheets of 3/4" plywood. I really like the radial arm saw for cutting the dado and the rabbit for cabinet construction. The table saw is not as fast when cutting a dado or a rabbit and you cannot see the results until your finished and turn over you material. If the blade is out of adjustment or dull and chipping the material it is not noticeable until your finished, so using a test piece is advisable. The radial arm saw has historically intimidated potential users with its open blade design. I will attest to the fact that a table saw is the most dangerous wood cutting machine in the shop and requires extreme attention to safety from the blade and the force of a kickback, which is capable of punching a 2x4 through a chain link fence after flying 10' past your hip. "WARNING" do not stand directly behind your material while pushing it through the table saw blade. I have seen kickbacks that almost killed the user. The radial arm saw has no hidden agenda. I have seen very good radial arms for sale as low as $25 for a barely used Powercraft 10" with a new blade. I bought that one and, many are available for $150. You can buy a new Craftsman for about $400 if you want it in the box ready for assembly.

[Phil B]

I do not have a power miter box or a table saw. The few miters I need I cut on my radial arm saw. I did make a miter attachment to make the job faster. I had not thought about problems with dadoes on a table saw. Even with my radial arm saw I avoid standing in line with the blade. I have heard of carbide tipped blades throwing a tooth. I keep my hands away from the blade's path when crosscutting. I have heard the blade can catch and force the motor carriage back toward the operator.