Sharpening Mulching Blades

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falcon
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Sharpening Mulching Blades

Post by falcon » March 2nd, 2021, 12:52 pm

This is probably a dumb question, but do you need to sharpen the curved part of a mulching blade? I assume so since it comes sharp when purchased. Lots of people online say no. I know...taking online opinions is dangerous. But the folks here are a lot more trustworthy than most other places online.

Assuming the answer is yes, I assume a hand file is the best way to achieve this?

Does anyone have file recommendations?

Thank you!

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MorpheusPA
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Re: Sharpening Mulching Blades

Post by MorpheusPA » March 2nd, 2021, 3:53 pm

You mean the part inward of the first few inches? Technically, not very much. Just get the gunk off and give it a rough sharpening; I use a mill bastard file on the entire blade to give it a "not very sharp" sharpening.

Razor-sharp blades will simply blunt themselves almost instantly anyway so there's no reason to bother. The inward part of the mulching blade cuts the grass into smaller parts as it bounces around inside the chamber, but doesn't perform the main cut. It's not critical if it isn't great, but should be sharp enough to cut the longer grass into smaller pieces--if I'm interpreting your question correctly.

As you move close to the center, the blade does not perform any appreciable cutting.

And technically, you should clean your blade after every use. Yeah, yeah, I know, we'll all get right on that one.

falcon
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Re: Sharpening Mulching Blades

Post by falcon » March 2nd, 2021, 4:20 pm

Image

Thanks, Morpheus. The circled part.

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MorpheusPA
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Re: Sharpening Mulching Blades

Post by MorpheusPA » March 3rd, 2021, 2:19 am

Yep. The outer edge cuts the grass. That part helps mulch the grass that bounces (technically, although I've never really been sure how much, they say it does). Inward of that, no cutting really gets done.

Just give it a general sharpening and keep it clean, like you would with the cutting surface. Neither need to be razor-sharp, just sharp-ish.

edslawn
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Re: Sharpening Mulching Blades

Post by edslawn » March 3rd, 2021, 9:02 am

I'm lazy and have to do three tractor blades that seem to get beat up on my hilly property, so I use a bench grinder for really bad dings and angle grinder with flap discs for finishing. Very effective. On that curve part, I just clean up a bit with the disc.


falcon
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Re: Sharpening Mulching Blades

Post by falcon » March 3rd, 2021, 12:52 pm

Thanks, guys. I have 10 blades to maintain (2 sets of 3 for my tractor, and 2 sets of 2 for the push mower), so we will see how I decide to do it. For now, I plan on using the mill bastard file by hand.

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MorpheusPA
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Re: Sharpening Mulching Blades

Post by MorpheusPA » March 3rd, 2021, 3:07 pm

One blade. And I'm lazier than either of you; I've sharpened it once in ten years. :-)

OK, that was just being super-lazy.

edslawn
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Re: Sharpening Mulching Blades

Post by edslawn » March 3rd, 2021, 7:28 pm

MorpheusPA wrote:
March 3rd, 2021, 3:07 pm
One blade. And I'm lazier than either of you; I've sharpened it once in ten years. :-)

OK, that was just being super-lazy.
No, I'm lazier!!

napper
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Re: Sharpening Mulching Blades

Post by napper » March 23rd, 2021, 3:30 pm

The All American Blade Sharpener works good on mulch blades or any blade.
Image

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