How to Sharpen a Mulching Blade? Know All Methods

Is your mulching blade used to cut clean but now it just rips, pulls grass, and leaves ragged tears? There is no need to look for a replacement, sharpening the blade would do the job for you. The mulching blades have to be sharpened every 10 hours of use to get satisfactory results. 

Most lawn owners do not sharpen the mulching blade that often. Therefore, it begins to give ragged cuts and leaves brown casting on your grass. So, there are some solid chances you failed to sharpen it as well, and now you are dealing with this issue. 

To be honest, sharpening the blade is not an uphill task at all. Anyone who can mow the lawn can sharpen the blades as well. Here is the step-by-step guide and some practical tips that would help you sharpen the blades to perfection.

How to Sharpen a Mulching Blade?

There are many ways to sharpen the mulching blade so it works best. You can do it with a metal file, cordless drill, bench grinder, hand-held grinder, sharpening jig. Here is how you can sharpen the mulching blade each way. 

  • Decide how you want to sharpen it – As stated above, there are many tools to sharpen the blade. You have to decide what tool to use first. You would surely love to go for the one that makes the job easy and quick, right? Sharpening the blade with a metal file is the easiest. However, do not go for a metal file just because I recommend it. Read the post till the end to figure out how you find sharpening the blade the easiest.
  • Have all the necessities – To be able to sharpen the mulching blade without any further delay, get all the necessities. You would need a sharpener, eye protection glasses, gloves, a plastic balance checker, and a vise.
  • Remove the blade – You can not sharpen the blade without removing it from the mower. It’s a bit tricky, you first have to disconnect the spark plug wire. Now you have two choices, you can tip the mower towards the front or take out all the fuel and turn it upside down. The latter option is better for newbies as it ensures easy access to nuts. 

Note: Since it’s your first time, examine the blade for a while or take a picture as you have to put it back the same way. Now it’s time to undo the nuts but make sure to place a piece of wood at a 90-degree angle to not end up bending the blade. If you can not handle it, hold the blade with one hand and undo the nuts with the other. Now, undo the nuts to move ahead with the plan.

All methods are explained below:

1. Sharpening Mulching Blade Using a Metal File 

A file is a useful metal tool specifically made to sharpen or smoothen metal objects. It has a rough surface, all you do is rub against the object to sharpen it. To sharpen the blade, here is what you have to do after removing it from the mower:

  • Fit and tighten the blade in a vise – Since the blade should not move while sharpening, you have to fit and tighten it into the vise. It would hold the blade securely from the middle so you can perform the job without any hassle.
  • Trace the angle on the cutting edge – Once the vise holds the blade tightly, trace the angle on the cutting edge and downstroke the narrow file in the same direction. Continue making strokes until the blade looks shiny and feels sharp.

2. Sharpening the Mulching Blade Using a Cordless Drill

A cordless drill is another power tool commonly used for this purpose. It’s the same power tool that we use to drill holes and drive screws. It readily becomes perfect sharpening equipment as you attach the sharpening stone or the grinding wheel. Here is the steps you have to follow to sharpen the mulching blades:

  • Wear eye protection – Sharpening the Blade using a cordless drill can be messy. Wear eye protection as it’s always better to be safe than sorry.
  • Turn on the cordless drill – To move ahead with the plan, turn on the cordless drill. There would be a button, spot, and press it to bring it into the functioning state.
  • Move on to the edge of the blade – To sharpen using a cordless drill, all you have to do is move it onto the edge of the blade in such a way that the blade touches the stone. Keep moving until the blade starts looking and feeling sharp.

3. Sharpening the Mulching Blade Using a Bench Grinder 

A bench grinder is an equipment having a motor and grinding wheels. It is specifically developed for sharpening objects such as mulching blades, tool bits, chisels, and gouges. You have to remove the blade and follow these steps to sharpen it to perfection.

  • Put on eye protection and turn on a bench grinder – While working with a bench grinder, you have to wear eye protection. Now that you are ready, turn on the bench grinder.
  • Push the blade against the disk – Push the blade gently against the disk to sharpen it. Again, you have to keep pushing it until the blade is shiny and sharp.

4. Sharpening the Mulching Blade Using a Hand-held Grinder

The hand-held grinder is a multipurpose handheld power tool you can use for cutting, grinding, polishing, and sharpening objects. It has a grinding wheel that does all the jobs perfectly. To sharpen the mulching blade using a hand-held grinder

  • Tighten the blade in a vise – Since you are using a hand-held grinder, tighten the blade in the vise. If the blade is secured properly, sharpening would be a breeze.
  • Push the blade against the disc – Now you have to push the moving disc of the handheld grinder against the cutting edge until it’s shiny and sharp.

5. Sharpening the Mulching Blade Using Sharpening Jig

As the name suggests, a sharpening jig is a sharpening equipment made to sharpen woodworking tools. However, you can use it to sharpen the mulching blades as well. Here is what you have to do.

  • Put on gloves and glasses – Put on gloves and glasses to protect your hands and eyes while sharpening the blade.
  • Swipe the cutting edge – Swipe the cutting edge of the blade in the sharpening jig and maintain the balance until it sharpens.

Tips to Follow While Sharpening a Mulching Blade

  • Clean the blade before attempting to sharpen it.
  • Do consult the user manual and follow the manufacturer’s instructions.
  • Swipe the sharpening tool gently to keep the shape.
  • A narrow file sharpens the mulching blades better than the wider ones. So, if you are planning to use a metal file, try sharpening the blades with a narrow one.
  • If you have a hard time balancing the blade, use a plastic blade balancer.
  • Replace the blade if it gets bent or damaged while sharpening.
  • Whatever sharpening tool you are using, check and maintain a balance to have an evenly sharp mulching blade.
  • Check or feel the sharpness by placing your thumb on it before putting it back on.
  • Wear protective gloves while sharpening the blade to protect your hands. Eye protection is mandatory only while using a cordless grinder and bench grinder.
  • Stop sharpening when the metal gets shiny and the cutting edge feels pretty sharp.
  • Sharpen your mulching blade more often. If not every 10 hours, every 25 hours of use.
  • Never forget to turn off the ignition before removing or sharpening the blade.

Frequently Asked Questions

Should mulching blades be sharp?

Yes, the mulching blades must be sharp. The well-sharpened mulching blades ensure even cutting and help you achieve a healthy lawn.

Do new mulching blades need to be sharpened?

No, usually the new mulching blades do not need to be sharpened. You would have to sharpen them up after a few weeks of abuse.

How often do you have to sharpen mulching blades?

You should sharpen mulching blades quite often. Sharpening after every 20 to 25 hours of use is highly recommended.

Leave a Comment