How to Sharpen a Lawnmower Blade (And How Often You Should Do It)

If your lawn looks ragged after mowing or your mower just doesn’t feel like it’s cutting the way it used to—it’s probably time to sharpen the blade. In this post, we’ll answer the most common questions about lawnmower blade sharpening, walk you through the DIY process, and explain why (for most people) it’s easier to just call Blade Butlers and let us handle it.

Q: How often should you sharpen your lawnmower blade?

The general rule: sharpen your lawnmower blade every 20 to 25 hours of mowing. For most homeowners, that means at least twice per mowing season—once in early spring, and again in mid-summer.

If you hit a lot of sticks or rocks, or your grass is thick and lush, you might need to sharpen more often.

Q: What are the signs of a dull lawnmower blade?

Here’s what to watch for:

• Grass tips look torn or frayed instead of cleanly sliced

• Your lawn turns brown or yellow after mowing

• The mower feels like it’s dragging or working harder

• You notice vibration or rattling under the mower deck

  
  

These are red flags that your blade isn’t cutting cleanly—and dull blades can actually stress your lawn and make it more prone to disease.

Q: Can I sharpen a lawnmower blade myself?

Absolutely. It just takes some tools, time, and elbow grease.

DIY Sharpening Steps:

1. Disconnect the spark plug – Always do this to avoid accidental starts.

2. Tilt the mower – Carburetor side up to avoid fuel and oil spills.

3. Remove the blade – Use a wrench or socket set.

4. Secure the blade – Clamp it in a vise or to a stable surface.

5. Sharpen the edge – Use a file, angle grinder, or bench grinder. Follow the original bevel (around 30 degrees).

6. Balance the blade – Crucial step! Use a blade balancer or hang it on a nail to ensure one side is not heavier than the other.

7. Reinstall and reconnect – Tighten the bolts and reconnect the spark plug.

   
   

Q: What tools do I need to sharpen a mower blade?

• Safety gloves + goggles

• Wrench/socket set

• Vise or clamps

• Angle grinder, bench grinder, or metal file

• Blade balancer (they’re around $5 and worth it)

  
  

Q: Can I sharpen my blade without removing it?

Technically, yes. But we don’t recommend it. It’s nearly impossible to get a clean, even edge without removing the blade—and you can’t properly balance it while it’s still on the mower. Unbalanced blades cause vibration, damage your mower, and lead to uneven cutting.

Q: Should I sharpen or replace my blade?

Unless it’s cracked, warped, or seriously chipped, sharpening is the way to go. A quality blade can be sharpened 5–10 times before it needs replacing. That’s more budget-friendly and more eco-friendly.

Q: How long does it take to sharpen a mower blade?

If you’re handy, expect it to take 30 to 45 minutes. A professional can usually do it in under 10. But for most folks, the biggest hassle is actually getting the blade off, sharpening it right, and reinstalling it safely.

Or… You Could Just Call Blade Butlers

We sharpen mower blades on-site from our mobile sharpening center—right from our sprinter vans. That means:

• No removing your blade

• No hauling it anywhere

• No guessing if it’s sharp or balanced

You just book the sharpening service, we show up, and your lawnmower will be ready to cut clean and smooth again.

Book Now and Give Your Grass the Clean Cut It Deserves

Whether your mower’s struggling or your grass just isn’t bouncing back after a mow, odds are it’s time for a blade refresh.

Let Blade Butlers take care of it—so you can get back to mowing, not maintaining.

Book a Sharpening Service | Call us: 801-895-7500