Are Lawn Mower Blades Made from High Carbon Steel?

Lawnmower blades are designed to slice through the grass without chipping or breaking when hitting hard objects. For example, the blade’s flexibility allows it to bump into walls, fences, rocks, and tree stumps. Since hardened steel can break upon contact, it might make you wonder if it’s supplemented with carbon.

Lawn mower blades are made from high carbon steel to allow them to flex when hitting hard surfaces without ruining their cutting power. Some mower blades are made with medium carbon content. The carbon steel provides excellent tensile strength while mowing.

Throughout this article, we’ll discuss why mower blades are made from high carbon steel, how you can sharpen them to make them more durable, and how long they last. We’ll also show you a few ways to make your high carbon mower blades last longer.

Why Are Lawnmower Blades High Carbon?

Lawnmower blades are high carbon to promote flexibility, strength, longevity, and slicing power. While not all mower blades have a high carbon content, almost all of them contain traces of carbon. Without it, most lawnmower blades would break when hitting hard surfaces.

Here’s a list of reasons lawnmower blades are high carbon:

• High carbon steel blades make lawnmowers slice through grass, weeds, and other plants with precision. You can sharpen lawnmower blades like a knife. In fact, some people turn their used mower blades into a blade sharpening hobby. They’re great for cutting all sorts of materials around the yard.
• Steel without carbon is often more prone to breaking, especially when it hits fences, rocks, and so on. If you’re worried about cutting grass near a fence, you can use a weed trimmer to edge the sides. Thankfully, your mower’s blades shouldn’t chip since they’re made of carbon steel.
• Lawnmower blades require flexibility to move with slopes, hard objects, and more. If they weren’t flexible, they’d crack, chip, or break the bolt and fly off the machine. Tensile strength and flexibility are crucial when mowing a sloped yard with a lot of obstacles.

As you can see, there are plenty of reasons lawnmower blades are made from high carbon steel. While it’s much more durable than hardened steel, it can be a little less costly. You can also use the mower’s blades to make all sorts of tools when you switch them for a new set.

USA Mower Blades claims lawnmower blades should be made with mid-level strength to let them flex; Otherwise, they won’t withstand the grass cutting process for several years to come.

How to Sharpen Carbon Steel Lawnmower Blades

To sharpen carbon steel lawnmower blades, follow these steps:

1. Remove the center bolt on the lawnmower’s blades after turning the machine off. Flip the mower on its side and look for a bolt that’s holding the blades under the deck. Loosen it and set it aside, then remove the mower blade with gloves while facing the blades away from you.
2. Sharpen the blades every 20 hours to prevent them from getting dull or chipping. Regular sharpening sessions will keep your high carbon lawnmower blades in good condition for as long as possible. Many people forget to sharpen their mower blades or think it’s unnecessary. However, it makes a significant improvement.
3. Slide the mower blades through the SHARPAL 103N Gardening Tool Sharpener. This handy tool lets you sharpen lawnmower blades, gardening shears, knives, and many other blades. Hold the ergonomic handle and slide the metal through it for smooth, even sharpness.
4. Apply a thin layer of cooking oil to the lawnmower’s blades, according to SF Gate. The oil stops grass, weeds, and other plants from sticking to the blades. Too much oil can overheat the blades or cake the grass clippings in the deck or bag. Only try this step if it’s encouraged by the lawnmower’s manufacturer.
5. Tighten the bolt and secure the blades to the lawnmower before mowing the grass. Replace the lawnmower’s blades in the same direction you removed them, tightening the bolt to ensure it doesn’t look uneven. Test the blades on a small patch of grass before mowing the whole yard.

This process ensures your blades are sharpened from end to end. It’s best not to sharpen them while they’re attached to the mower because there’s no way you’ll be able to sharpen the whole blade. Also, don’t wait too long between sharpening sessions, or your lawnmower’s high carbon steel blades will corrode.

How Long Do Mild Steel Mower Blades Last?

Carbon steel mower blades last between 1 to 2 years before they need to be replaced. Check the blade’s quality and brand before determining how many hours you’ll get out of them. Remember that hardened steel isn’t the best choice for lawnmowers because it can break easier on direct contact.

Many people believe lawnmowers don’t need much maintenance, but that couldn’t be further from the truth. Failure to sharpen the blades, change the filters, and check the spark plugs will result in a short-lived machine. You should maintain your lawnmower as much as your vehicle.

You’d be surprised by how big of a difference sharpening your lawnmower’s blades can make. A few minutes of sharpening can be the difference between beautiful lawn lines and a flat, trampled patch of grass. It’s more than worth the effort, so why not try it and see if you notice an improvement?

Unfortunately, misuse and improper storage can shave weeks or months off of your mower’s blades. High carbon steel lawnmower blades should last a long time, but they can get rusty or dull if you don’t sharpen them or follow the instructions in the next section.

Can You Make High Carbon Steel Lawnmower Blades Last Longer?

You can make high carbon steel lawnmower blades last longer by keeping them out of the rain, sharpening them regularly, and tightening the connecting bolt. When the blades are thin or corroded, it’s time to replace them with a new set.

Try these tips to make your lawnmower blades last longer:

• Store your lawnmower in a shed, garage, or under a tarp. Lawnmowers can get rusty, making the blades porous, fragile, and unlikely to cut the grass. They can also create unwanted situations if they break off the mower while you’re trimming the lawn. Don’t let the rain ruin your lawnmower!
• Sharpen the blades every 20 to 30 mowing sessions, depending on how long you mow the grass. Much like sharpening mulching blades, you need to keep your lawnmower’s high carbon steel blades in working condition. If you don’t, they’ll create uneven patches and partially cut grass.
• Tighten the nuts and bolts on the lawnmower’s deck after every time you cut the lawn. The vibrations and bumps caused by mowing the lawn will slowly loosen these parts on your mower. After a few sessions, the blades will become loose and cut uneven lines in the grass.

While there’s a lot you can do to get the most out of high carbon steel mower blades, they all have their expiration dates. Don’t try to push corroded, rusted, or chipped lawnmower blades past their limits. If you do, they can ruin the lawn or break the mower. It’s best to get a new set and start new.

In Conclusion

High carbon lawnmower blades are sharp, durable, and made to last for several years. The quality, thickness, and length directly impact how long they last, as do the surfaces you’re cutting grass on. Remember to keep your lawnmower out of the rain to keep the blades from rusting and corroding.