What To Do If Your Lawn Mower Blades Are Bent

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It could happen to anyone — you're out mowing your lawn when suddenly your blade hits a hidden branch, stump, or rock. Sometimes, all this does is dull the edge, and you can easily sharpen the mower blade with a specialized garden tool sharpener, a metal file, or a grinder. In other instances, though, more damage is done. If your mower begins to vibrate harshly or the cut becomes annoyingly uneven, then you may have a bent blade on your hands. So, what do you do in these situations?

Well, the first thing to do is stop mowing. One of the biggest lawn-mowing mistakes to avoid at all costs would be to cut your grass with a bent blade. A bent blade can potentially destroy the mower's crankshaft, a repair that is not covered by the manufacturer warranty. If the engine damage is bad enough, you might be looking at a costly lawn mower replacement.

To see if you've actually got a bent blade, tighten the fluid caps, remove the spark plug to prevent accidental startups, and lay the mower on its exhaust side. If you can't discern the bend right away, remove the mower blade carefully to exam it closer. Even a small bend could throw off the balance of a blade and lead to uneven cuts and engine wear. You might be able to bend the blade back in place by putting it in a vice and banging the warped section with a hammer, but typically, the best practice is to replace it.

It's no secret that the average American spends a lot of time and money on lawn care, so it makes sense to find savings whenever you can. However, straightening a bent lawn mower blade yourself could be laborious and potentially risk keeping it out of balance and creating bends in other sections. "But replacement blades cost money!" Yes, they do. However, what's going to cost more? A replacement blade or a replacement lawn mower? Depending on your mower and the type of blade it requires, you're looking at $20 to $50 for a new piece and a few minutes worth of work to install it. You just have to check that the blade is compatible with your mower model, meaning the hole shape, size, and placements match the old unit and the length is appropriate for your mower deck.

It's worth knowing, however, that just because the blade is new doesn't mean it's perfect. You should still check the sharpness of the blade and balance it before putting it on the mower. You can achieve this with an inexpensive kit like the Arnold Universal Blade Sharpening Kit. It's a quick and easy solution from Home Depot that comes with a blade balancer and sharpener, letting you make simple adjustments to prevent wobbling, ensure clean cuts, and avoid unnecessary mower wear. Once the blade is balanced, get it back on your mower and keep cutting grass. Just be careful not to hit any more stumps.