When you use your lawn mower to cut your grass, the blades of the blade can dull over time. Sharpening the blade can help keep it in good condition and improve your yard’s appearance.
If you sharpen your blade without grinding down the same amount of metal from each side, it can become unbalanced. You can correct this by filing a little metal from the heavier side until it balances.
Materials
Whether you are making a knife for a hobby or for work, it is important to use the right materials and tools. This will ensure that you create a blade that is durable and sturdy.
There are several different types of steel that can be used for this project, including mild steel, high-carbon steel, and stainless steel. All of these can be purchased at a hardware store or online, and are easy to work with.
The type of steel that you choose will have a significant impact on the quality of your final blade. It is best to use a high-carbon alloy, as this will provide the maximum durability.
Heat treatment is an important process that many blade smiths utilize to increase the durability of their finished product. It is often performed during the forging stage, and it helps to realign and strengthen the structural bonds that hold the blade together.
Cutting Edge
A blade should be sharpened at least once a year to maintain optimal cutting efficiency. Unsharpened mower blades can make uneven cuts and uproot bushes, increasing tool operation time and fuel consumption.
To sharpen a lawn mower blade, place the flat side of a metal file flush against the cutting edge. File until bright metal shows, then turn the blade and repeat the process on the other end of the blade.
When sharpening, take care not to remove too much metal. This will make the blade less balanced and cause the lawnmower to wobble during use.
Balance the blade by hanging it on a nail secured in a stud. If one end is heavier than the other, file the lighter side to reduce the weight.
A balanced blade will prevent excessive vibration that can damage the mower’s motor and put undue stress on it. If the blade is not balanced, hang it from a screwdriver and test its balance. If one end points up, file the other side until the whole blade is even on the screwdriver handle.
Handle
A good handle makes a blade easier to use and keeps it from slipping out of your hands. This is especially important on a lawn mower, which can be hard to control with bare hands.
Handles are often made of ash or hickory. Cecil prefers raw ash handles, noting that they’re more flexible and have a better feel in your hands than shellac-coated ones.
If you choose a wood handle, first rough shape it using a wood rasp or belt sander. Make sure the bolsters are rounded, and mark them.
Once shaped, sand the entire handle with successively finer grits of sandpaper until it is smooth and attractive.
After finishing, treat the new handle with boiled linseed oil, to protect it from moisture and keep it smooth. This is particularly important if you plan to use the knife with a curved blade.
Finishing
Sharp mower blades cut grass evenly and efficiently, improving the appearance of your yard. Dirt, sand and debris can quickly dull lawn mower blades, leaving ragged edges that make your lawn look less than professional and may even be more susceptible to pests and disease.
When a lawn mower blade gets dull, it should be re-sharpened to keep it working properly. This is a simple, inexpensive activity that should be performed at least once a year to keep your yard looking great.
Once you’ve re-sharpened your lawn mower blade, it’s important to make sure it’s balanced before you re-attach it to the mower. You can check this by using an inexpensive balancing cone from the hardware store.
Then, use a hand file or angle grinder to sharpen the cutting edge on both sides of the blade. Repeat this process until both edges are sharp. You may need to do this several times before the blade is balanced enough to be used for mowing.