How Sharp Should Blades Be?

panabiker

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I just bought a pair of new blades made by Arnold. I noticed that the edges are painted and are not that sharp but very straight. I now wonder if I have been sharpening too much unnecessarily. Another point of reference is that the nylon strings used in the trimmers are even duller and yet the areas I trimmed don't seem to suffer tearing or other illness associated with bad blades. Any thoughts?
 

Carscw

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I just bought a pair of new blades made by Arnold. I noticed that the edges are painted and are not that sharp but very straight. I now wonder if I have been sharpening too much unnecessarily. Another point of reference is that the nylon strings used in the trimmers are even duller and yet the areas I trimmed don't seem to suffer tearing or other illness associated with bad blades. Any thoughts?

First stop wasting money on Arnold blades. They just don't last long.
You do not want to sharping blades to a razor edge. They will just dull fast and you will go threw more blades.
A new blade is as sharp as it needs to be and the pitch is what has been found to be the best for cutting grass and max life of the blade.

Most trimmer line is really not any wider than the edge of a blade.
The speed if the line is faster than most blade tip speeds
 

possum

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I noticed the same thing. The blades on the new MTD mowers are very sharp so that new mower really cuts nice. But the replacement blades are pretty dull. I suppose product liability has something to do with it. The blades are the same as far as I can tell. Just sharpen them some more if you wish or use as is if they suit your needs. I like the Arnold blades.
 

Rivets

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A good sharp blade cuts faster and leaves the lawn looking better than a dull blade. All blades leaving our shop are sharpened to the point that they will cut you if you're not careful. New blades are not to that point for safe handling and $$$$. On the average lawn a sharp blade will last a season for a homeowner.
 

okiepc

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I sharpen my blades 3-4 times a season, I sharpen it as sharp as I possibly can & you can tell the difference when you start mowing, just a clean cut. The blade never gets really dull, but I like sharp better. :thumbsup:
 

Fish

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I have noticed that a lot of the brand new blades are very sharp, but are end dipped in thick paint for safer/easier shipping, which chips off quickly
when mowing.
 

Carscw

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For a homeowner that can take the time to sharping blades after every few cuts then make them razor sharp. The thing is when you give them a razor edge they dull and chip faster and they don't last as long.

For some of us cutting 20 yards a day we do not have time to change blades 4 times a day the factory puts a edge on the blade that has been found by many study's to give the best cut and longest life of the blade.
You say putting a razor edge gives a better cut. Ok maybe for one cut then the edge is gone. A high lift blade sucks sand up do you not think that dulls the blades.

And yes they do dip them in a rubber paint for shipping. For safety and so they don't rust.
 

tybilly

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carscw..how many times do you rotate blades (from new to junk)...and I was told that razor sharp caused a grass fungus...not sure how true that is.
 

Carscw

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carscw..how many times do you rotate blades (from new to junk)...and I was told that razor sharp caused a grass fungus...not sure how true that is.

The thing is that a razor sharp blade only stays razor sharp until it cuts grass then you end up with a flat edge. The factory edge and pitch has been found after many study's to be the best for the grass and longer life of the blade.

A good good blade will last me about a month. Around 300 grass cuts. I use them till the fins get to thin.
If I was to sharping my blades razor sharp I would get maybe 50 cuts out of them.
A pine cone will chip a razors edge.
 
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