Great Blade Sharpening Video

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  • Updated 12 months ago
So a lot of you are familiar with the Lawn Care Nut videos.  Allen posted a video about blade sharpening that has some really good closeups of his new St. Augustine lawn being cut with both dull and freshly sharpened blades.  Here's a link to his video:

https://www.youtube.com/watch?v=JeL0_kww6Tw

Now given the type of abuse a mower blade sees and the type of damage they rack-up in use (dents, chunks missing etc.), I personally don't think those Scotchbrite Roloc discs are the best option.  I prefer flap discs, as do many here according to posts I've seen in the past.  A flap disc looks like this:


It's basically strips of coarse sandpaper layered into a disc.  The Scotchbrite Roloc discs may work extremely well for putting a finer finish on a blade once the heavy material has been removed and the deep imperfections corrected, but I think the flap disc is still likely better as a first step and maybe overall.

Has anyone else tried the Scotchbrite style discs?  Maybe I'm wrong?

Anyway, the real point of showing the video is Allen's excellent closeup evidence of how a sharp blade really makes a nice cut through the grass blade and avoids damaging it.  He also goes on to say how much nicer the mower operates and how much easier it cuts, how there's less uncut blades after cutting, and he plans to sharpen before each cut to see how much of a difference it makes to his lawn's "dominance". :-)
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Blue Angel, Champion

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Posted 1 year ago

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TheAtomTwister

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Johnny Mow has the perfect tool for the job. https://www.youtube.com/watch?v=QcB6yq_0BeY
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(a)Typical Engineer

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The Ego blade steel is pretty soft; and I use a 120 grit flap disk, which is actually pretty far worn so it's likely more like 240 grit, which is WAY more than enough to touch up the edge.
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Troutboy

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Damn, that RBG712 is $400!!!
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Troutboy

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Here is a solution that is cheaper, still $$$. https://www.amazon.com/Yellow-Hornet-...
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(a)Typical Engineer

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Before you try a grinding disk, or even a flap wheel, you really need to put a file on it just to see how soft the steel really is.  I'm pretty sure that three passes with a decent file will be enough, which you might actually be able to do with the blade still on the mower. 

I just might try that: hand file after every mow to touch up the edge, and then pull the blade off and touch-up/re-profile with the flap disk once a month.
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Blue Angel, Champion

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The only issue with using a file is the curved section of the cutting edge. Yes curved files exist, but their point (line) contact tends to groove things if you're not careful. Can be done, I guess.
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Ken, Champion

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Again, I use this $20 sharpener with great success. Takes four or five passes and it's done: https://www.amazon.com/Smiths-50603-Mower-Blade-Sharpener/dp/B00VTO5N2G/ref=sr_1_1?ie=UTF8&qid=1...
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(a)Typical Engineer

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@Blue, true about the curved part, but for my yard, mainly the edge near the end gets dinged pretty good.  Here's the cut-down HL blade after two yard outings; and I touched it up with the hand file pictured (very light, maybe three passes total, and one on the back side to knock down the burr).

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Blue Angel, Champion

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Good point.
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Dane Earley

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For those of you using a flap disc, are you using a 2" or 3" ? I may try this method for my next sharpening.
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Dane Earley

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Skillz! I guess I meant easier to control/better hand positioning.
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Jacob, Champion

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Skillz is right. After about 20 sharpenings, you can do it in your sleep.
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Blue Angel, Champion

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Fine grit is key, like Jacob said.  I believe mine is 120 but I'd take an even finer grit, these discs are very efficient at removing material.  Smooth light passes until you get the feel of it, then it's a walk in the park. :-)
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(a)Typical Engineer

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I use 4-1/2" or 5" flap disks on my Milwaukee M18 Fuel Grinder.
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Jacob, Champion

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I dull my flapper on cement if its new. It polishes the blade better. Make sure you dont heat up the blade. Light passes. You dont want to make it brittle.
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Dane Earley

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I sharpened my blade today with a flap disc on a grinder. It was quick and worked great. I'm sold on this method vs. my diamond particle file. Boy did the sparks fly!