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Discussion Starter #1
I have a x300 and just received two new blades. I can press my thumb on the "sharp" side and rub it up and down hard, and it won't even come close to causing any discomfort - let alone cut into it. I suspect it would even have a hard time with an carrot.

What's up with that? How easily should the blade be able to cut a carrot?
 

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I have a x300 and just received two new blades. I can press my thumb on the "sharp" side and rub it up and down hard, and it won't even come close to causing any discomfort - let alone cut into it. I suspect it would even have a hard time with an carrot.

What's up with that? How easily should the blade be able to cut a carrot?
I believe the spec on their new blades is about a 1/16 flat edge. The thought is they will be a bit tougher if a hard object is hit.
 

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Probably wrong, but I sharpen to a sharp edge :hi:The sharper the better it my motto :cheers::cheers:
 

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Probably wrong, but I sharpen to a sharp edge :hi:The sharper the better it my motto :cheers::cheers:
I do the same thing. I've been told to leave them a little dull, but there's something about mowing with really sharp blades that leaves you with a good feeling.
 

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I always grind my blades sharp also, but after the first mowing the sharp edge is gone.
That’s just it. If you sharpen youy blades to a knife edge they will be dull within minutes and will require sharpening way too often. Then when you are constantly sharpening you are removing material and they need to be balanced more often.

The graphic I posted above is right out of a Deere mower manual.
 

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That’s just it. If you sharpen youy blades to a knife edge they will be dull within minutes and will require sharpening way too often. Then when you are constantly sharpening you are removing material and they need to be balanced more often.

The graphic I posted above is right out of a Deere mower manual.
You're right. Sometimes old habits die hard.
 

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I have a couple sets of blades for my X500 so that I can easily rotate them and always have a set ready. All of the blade sets I purchased from JD were razor sharp right out of the box.

I think a lot of it has to do with how much debris you run over while mowing.

I always keep a pretty fine edge on my blades. I don't find that it makes them dull any quicker and they certainly cut better. When mulching leaves in the fall sharp blades work MUCH better. I sharpen my blades twice a season and it usually only involves a bit of a touch up with a flap disc, no deep grinding needed.
 

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Your blades are just as they should be.



Dimension “B” should be 1/64”.
You know, all this talk about keeping your blades a bit dull. It is true that the graphic above appears in the manual. But... it is also accompanied by these instructions:

• Keep original bevel (A) when grinding.
Blade should have 0.40 mm (1/64 in.) cutting edge (B) or less.
• Balance blades before installing.


Note the "or less" part? They are saying the DULLEST it should be is 1/64" (0.015). These are blades for grass, not brush hogging. :)



 

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You know, all this talk about keeping your blades a bit dull. It is true that the graphic above appears in the manual. But... it is also accompanied by these instructions:

• Keep original bevel (A) when grinding.
Blade should have 0.40 mm (1/64 in.) cutting edge (B) or less.
• Balance blades before installing.


Note the "or less" part? They are saying the DULLEST it should be is 1/64" (0.015). These are blades for grass, not brush hogging. :)



This has been discussed at length before in here.
I think this falls into personal preference depending on conditions.
Many of you guys have immaculate lawns, doofuses such as myself have rough conditions.
Keen blades in my yard would have their edges deflected in short order.
 

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The thing with a sharp edge is that it folds over if it hits anything, a twig, sand etc. that makes a larger dull spot then having a slightly blunt edge, which is to big to bend with slight impacts.

That said, do what you want I’m not going to subscribe to this thread as it doesn’t effect my machine so I’m not interested in spirited debate or arguing about it.
 

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Our "soil" is so sandy and our "grass" is like cutting wire so I have to sharpen my blades every other mowing. Every 2 weeks. And a new set of blades almost makes it through a season.
 

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Discussion Starter #15
That’s just it. If you sharpen youy blades to a knife edge they will be dull within minutes and will require sharpening way too often.
This is what I don't get. IMO A 1/64th edge is already "dull" - if you are trying to cut anything. I just replaced my blades after a hard 20 hours - over gopher mounds, a few rocks, many twigs, etc and they are close to what my new ones arrived as.

So if sharp when put on, after some hours they will be at the 1/64th - so what's the difference?

And on a mulching deck/kit, I would think any extra sharpness would be a plus.
 

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This is what I don't get. IMO A 1/64th edge is already "dull" - if you are trying to cut anything. I just replaced my blades after a hard 20 hours - over gopher mounds, a few rocks, many twigs, etc and they are close to what my new ones arrived as.

So if sharp when put on, after some hours they will be at the 1/64th - so what's the difference?

And on a mulching deck/kit, I would think any extra sharpness would be a plus.
That was the point of my previous post. I suspect folks are misinterpreting the illustration in the manual that shows the 1/64" edge. At first glance it appears to be telling you to sharpen the edge to approx. 1/64" but... the instructions listed below the drawing says the edge should be "1/64 or LESS". So the manual is saying the blades need to be resharpened whenever the edge dulls to 1/64".

If you look at the way commercial mower blade sharpening machines like the Oregon units are setup, they maintain the correct bevel but the edge is ground to a fine edge.

Also as previous stated, the new blade sets that I have purchased from JD have been wicked RAZOR sharp right out of the box.
 

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Our "soil" is so sandy and our "grass" is like cutting wire so I have to sharpen my blades every other mowing. Every 2 weeks. And a new set of blades almost makes it through a season.
AH HAH! So we have finally identified the disadvantage in living in beautiful warm weather year around. You have to sharpen your mower blades more often.....

We just KNEW there had to be something.......Somewhere..........Sometime........Whew, finally, we found it......

So now when I am out plowing snow at 3am, I will think to myself, "Just imagine poor old GTT'er Robnik. He is sharpening his blades while we are making seasonal implement swaps."....:laugh::lol:
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It's important to watch as the blades wear as you lose the square edge at the end of the blade, you can start to see the lines of grass which aren't cut or are bent over and the quality of the cut drops dramatically.

Actually, the outer 5" to 7" of the blade is what does the vast majority of the important cutting in getting a top quality cut. I have seen some people sharpen the entire length of the blade from end to center bolt mount. That's a great way to get a blade out of balance when you start removing material in an effort to put a knife edge on that which was never meant to be removed.....
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When you are either swapping out blades or removing them to sharpen them one of the most important things you can do to maintain the best possible cut is to scrape the underside of the mower deck and remove all the accumulated grass. All of the extra grass stuck under the deck reduces the air flow under the deck which prevents the deck from "lifting the grass" up straight before cutting it.

The extra clumps under the deck also reduce the grass clipping movement, both of which are critical to getting the best cut out of your deck. A clumped up deck doesn't evenly discharge clippings, which is obvious on a well kept lawn.
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If you want to minimize the damage to the underside of the deck when "scraping it", try using a wooden paint stir stick. It has the shape to scrape and get the corners and its sturdy enough to get the job done. It also doesn't damage the paint like a metal putty knife or scraper because the paint stir stick doesn't have pointed corners to damage the paint under the deck.....The 5 gallon stir sticks work great for the larger decks as you can reach across the deck much further plus they are plenty strong.
 

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I just flip my blades over when they get dull..... :unknown:
 

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