DIY replacement cutting blade

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I've got a Greenworks 40v 19" walk behind mower, and I love the thing. One thing I don't like is that the cutting blade seems to be relatively soft cheap steel, and it doesn't hold an edge very long at all. Electric mowers don't have a lot of surplus cutting power, and the difference between a dull blade and a sharp blade is very easy to notice. Much more so than in a gasser.

Has anyone got experience or recommendations for making a new blade, or perhaps cross-applying a better quality blade meant for a different mower? It doesn't look easy, but it doesn't look impossible either.
 

BlazNT

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I've got a Greenworks 40v 19" walk behind mower, and I love the thing. One thing I don't like is that the cutting blade seems to be relatively soft cheap steel, and it doesn't hold an edge very long at all. Electric mowers don't have a lot of surplus cutting power, and the difference between a dull blade and a sharp blade is very easy to notice. Much more so than in a gasser.

Has anyone got experience or recommendations for making a new blade, or perhaps cross-applying a better quality blade meant for a different mower? It doesn't look easy, but it doesn't look impossible either.

We have a guy around my area that does cryo treatments to mower blades. Take him a new blade and he hardens it with very cold stuff. It is the best you can get if they only have OEM blades for your mower. You should check and see if someone around you does this.
 

bertsmobile1

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Are you sure it is steel ?
A lot of electric mowers use aluminium blades, which like you have mentioned dull very quickly.
 
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Are you sure it is steel ?
A lot of electric mowers use aluminium blades, which like you have mentioned dull very quickly.

Interesting- the weight and observed oxidation on the part seem right for mild steel, but I'll check again with a magnet.

I'm also looking into sharpening tools. I don't mind popping it off and grinding a fresh edge each month, I just don't have an appropriate tool for a blade this big.

I've seen some sharpeners that attach to a common drill and have a beveled stone set against a nylon backing guide. I've never tried that kind but it looks cheap and easy.
 

bertsmobile1

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Interesting- the weight and observed oxidation on the part seem right for mild steel, but I'll check again with a magnet.

I'm also looking into sharpening tools. I don't mind popping it off and grinding a fresh edge each month, I just don't have an appropriate tool for a blade this big.

I've seen some sharpeners that attach to a common drill and have a beveled stone set against a nylon backing guide. I've never tried that kind but it looks cheap and easy.

Most do it with an angle grinder by eye.Others use a die grinder or even a Dremmel tool with a stone in it.
There are a million different "miracle sharpens everything " tools out there with a stone or metal disc covered with diamond dust.
If it will sharpen a plane blade it will sharpen a mower blade.
The cutting angle is not that critical +/- a few degrees makes little difference.
The real important thing is the cutting tip.
Make it knife sharp & you will need to sharpen it every time you use it
 
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Most do it with an angle grinder by eye.Others use a die grinder or even a Dremmel tool with a stone in it.
There are a million different "miracle sharpens everything " tools out there with a stone or metal disc covered with diamond dust.
If it will sharpen a plane blade it will sharpen a mower blade.
The cutting angle is not that critical +/- a few degrees makes little difference.
The real important thing is the cutting tip.
Make it knife sharp & you will need to sharpen it every time you use it

Yeah I gave it a grind with my dremel last time, but the stone bits I've got were meant for soft materials and wore awfully fast. Maybe I finally have an excuse to get handheld angle grinder, yay!!

I use a household knife sharpener for my Robomow blades, and it's perfect. But those blades are much thinner- stamped sheet steel, probably whatever metric is closest to 16ga.
 
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