How to Sharpen Blades: The Ultimate Guide

It’s no secret that keeping your blades sharp is important. A dull blade can cause all sorts of problems, from decreased accuracy to increased frustration. This blog post will discuss the best ways to sharpen your blades and keep them in top condition!

Why Is It Necessary to Sharpen Lawn Mower Blades?

A dull lawnmower blade pulls and rips the grass blades, weakening the plant and making it more likely to get diseases. On the other hand, Sharp blades cut neatly and quickly, allowing the plant to quickly repair and recover. Lawnmower blade sharpening also lets you finish your lawn-cutting chore faster and with less stress on the mower.

These steps will work for any walk-behind mower.

Project Step by Step

Step 1: Remove the Lawnmower Blade

  • Disconnect the spark plug.
  • To prevent your car from starting, pull the spark plug wire away from the spark plug. This is possibly dangerous. Tape or tie it back so that you don’t accidentally touch the spark plug again.
  • When you are working on the blade, always remove the spark plug. If the piston is at the top of the compression stroke, a slight jolt to the blade may cause it to pass through the hump and into the power stroke. If that happens, the blade will move quickly and could break your hand!
  • Tip the mower on its side.
  • Turn the lawnmower on its side with the air filter and carburetor side up. This will stop oil and gas from dripping into the air filter.
  • The carburetor is usually straightforward to locate because it is connected to the engine through throttle wires. You’ll prevent the smoke cloud generated by leaking oil the next time you start your mower if you keep this side up when you tip it over to access the blade. Certain mowers have gas caps with air holes, which may leak a small amount of gas onto your garage floor; thus, work outside or have a rag nearby to wipe up drips.
  • Mark Your Blade.
  • Before removing the old blade, spray-paint it to know which way to replace it.
  • Mower repair professionals say homeowners’ biggest mistake is installing a blade upside down after sharpening it. The blade won’t cut, and the homeowner will become frustrated trying to figure out why.
  • Keep a spare blade at home. You’ll need it if the store is closed when you need to replace your blade!
  • Remove the Blade
  • Place a 2×4 between the blade and the deck to clamp it.
  • With a long-handled wrench, loosen the bolt (or nut). Turn it counterclockwise to remove the bolt and blade.
  • The blade is usually attached to the mower with a bolt or nut. It is usually very tight, and you will need to use clamps to loosen it. The 2×4 approach we demonstrate is straightforward, quick, and secure. Use your foot sparingly!
  • Put the mower back on its wheels. Then reinstall the blade on the mower.

Step 2: File the Blade

  • Hold the blade in a vise and sharpen it with a mill bastard file. The angle you use to sharpen it should be the same as before.
  • File until the blade is “butter-knife” sharp.
  • If your blade is dull, you can sharpen it or replace it.
  • You can sharpen a mower blade with a hand file. Mower blades are made from soft steel, so it won’t take many strokes to sharpen them. Make sure the file is clean, sharp, and at least 10 inches long.
  • Grinders can also work, but they are much more quickly. (Professional use them this way.) However, they are more difficult to control, and you might overheat the blade and ruin it.

Step 3: Check the Filing Angle

  • Filing should be done in the same direction as the cutting angle.
  • Sharpen your blade from the top side to get the longest-lasting edge.
  • Files cut in one direction only- on the push stroke. The file will feel like it is cutting into the metal if it is sharp. The file might not be sharp, or you might not be pressing down hard enough if you do not feel this cutting action.
  • Don’t make your blade razor-sharp. It will dull quickly. A “butter-knife” sharp should be enough.
  • It can be tough to keep mulching blades sharp. Mulching blades might have longer or curved cutting edges, necessitating different sharpening tools.

Step 4: Check Blade Balance

  • Before putting the blade back on, hang it on a nail to ensure balance.
  • If one side of the blade dips, you need to file off some more of that side.
  • Vibrations are caused by an unbalanced blade. The bearings or shafts might break.

Step 5: Reinstall the Blade

  • Reinstall the blade by screwing in the bolt.
  • Put the 2×4 back in and tighten the bolt with your socket and breaker bar.
  •  Insert the 2×4 reverse to tighten the bolt and use the breaker bar. This will help you apply more pressure and ensure that the bolt is tight. Mower sharpening professionals say that people’s second most common mistake is not tightening the bolt enough. A loose blade can throw off the engine timing and make it difficult to start up your mower.

For more information about how to sharpen your blades, click here.

Frequently Asked Questions About Blades Sharpening

What Is Sharpening a Blade Called?

Naming a blade (honing or sharpening) is often mistaken. The traditional “honing steel” does not grind or sharpen the blade. Its true function is to re-align a curled edge rather than remove metal from the edge.

How Are Blades Sharpened?

The blade of a knife can be made sharper by rubbing it against a hard metal or ceramic “steel.” This straightens the blade, which may have been bent from use. However, this does not mean that the blade needs to be completely resharpened.

What Does Sharpen the Blade Mean?

Knife sharpening is the process of making a knife sharper by grinding it against a hard, rough surface. This is typically done using a stone but can also be done with sandpaper or other flexible surfaces with hard particles.

Is It Worth Getting Knives Sharpened?

Sharpening a knife means shaving off a bit of metal to make the knife sharp again. Sharpen your knives twice or three times a year if you use them every day. Honing a knife with honing steel helps keep the knife’s edge aligned and makes it sharper.

What’s the Difference Between Honing and Sharpening a Knife?

Honing and sharpening are two different things. Honing keeps the blade sharp by pushing the knife’s edge back to where it should be. Sharpening makes your blade sharper by removing parts of it.

How Often Should You Sharpen Mower Blades?

You should sharpen your mower blade after 20 to 25 hours of operation. This will keep your lawn looking healthy and help maintain the mower. However, if you mow more often, you will need to pay more attention to the blades. Another way to maintain your mower is to build a shed kit to store your lawn equipment. There are various kits available in the market to choose from, which are easier to build than starting from scratch. You can consider buying or building a shed with a ramp to prevent your lawn mower from scratching or hitting the base of the shed.

Should I Sharpen New Mower Blades?

Lawnmower blades that are brand new do not need to be sharpened because they are always sharpened during manufacturing. However, lawnmower blades generally need to be sharpened at the beginning of each new season.

What Is the Last Thing You Must Do After Sharpening a Knife?

If your knife is made of grade 304 stainless steel, just wipe the blade with water. If it is made of carbon steel, after sharpening, clean it with water and then apply some cooking oil.

Why Should a Knife Have a Full Tang?

A full tang knife has a blade that goes through the handle. This makes it stronger, so you can apply more force to the blade without breaking. Some knives have a full tang, even if you can’t see it from the outside of the handle.

Do You Need to Strop After Sharpening?

Stropping is the final step in attaining a razor-sharp knife edge. Stripping removes the microscopic-level irregularities of the edge after you’ve sharpened your knife to generate a burr and then refined the burr off. As a result, you have a razor-sharp edge.

Do Whole Foods Sharpen Knives?

Do not take your dull knives or garden tools with you when you go grocery stores. We will sharpen them at the truck while you shop. The Howe Sharp truck goes to many stores regularly, including Whole Foods and farmers markets.