The 45 degree angle will be more resistance to damage and wear but will also be duller and be prone to tearing not cutting of the grass.
Let's talk about blade sharpening?
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Hammermechanicman
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You won't see much difference. A rotary mower doesn't really cut grass but rips it using Inertia. Talk to a pro golf course senior groundskeeper sometime if you want to know about reel vs rotary mowers and how they cut grass.
When a rotary mower blade is very sharp it will give a cut nearly equaling a reel mower but that will last a short time depending on factors like type of grass and moisture in the grass. Lush green grass is less abrasive than dry grass. Once the edge rounds over the angle doesn't matter. They will cut the same. There is a reason golf courses use gang reel mowers. As one guy put it. You "cut" the fairways and "chop" the rough. I have had customers bring in mowers with the blade on upside down and they didn't realize it. The biggest difference in the grass you will see is dull blades leave the ends of the grass ragged and those ragged ends turn yellowish or grayish a couple days after mowing. Especially if the grass is dry and needs water. A sharp or dull blade moving at 250mph will rip the grass in half and it will look the same that day but not in a couple days.
When a rotary mower blade is very sharp it will give a cut nearly equaling a reel mower but that will last a short time depending on factors like type of grass and moisture in the grass. Lush green grass is less abrasive than dry grass. Once the edge rounds over the angle doesn't matter. They will cut the same. There is a reason golf courses use gang reel mowers. As one guy put it. You "cut" the fairways and "chop" the rough. I have had customers bring in mowers with the blade on upside down and they didn't realize it. The biggest difference in the grass you will see is dull blades leave the ends of the grass ragged and those ragged ends turn yellowish or grayish a couple days after mowing. Especially if the grass is dry and needs water. A sharp or dull blade moving at 250mph will rip the grass in half and it will look the same that day but not in a couple days.
sgkent
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I am confused by the concept of harsh landscapes mean duller blades. In my world, harsh landscapes would mean sharpening more often. It is like saying if I cook a lot more the kitchen gets dirtier quicker. That means more effort goes into cleaning it, not we allow it to get dirtier because we cook more often.
Hammermechanicman
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I am pretty amazed at the gator blades with the fusion edge. Put a set on my ferris 3100 a couple years ago and haven't needed to sharpen them yet. I mow 4 acres. The original marbain blades would go a whole season between sharpenings.
I would disagree with that one. Usually mower blades, well, OEM mower blades are made of inferior steel. From what I've used Oregon has the best steel.
I would say used truck leaf springs would be a better choice.
More acute the angle, the sharper the blade CAN be. So at 30 and 45 degrees, both can be sharp. The 30 will be sharper but the 45 has more steel at the cutting edge and will last longer till the edge fades/disappears. Hatchets have say 30 degree bevels. Japanese straight razors can be in the low teens or less. Sharper but dulls faster.
Use the factory bevel angle and you will be fine.
My 4 cents on sharpening.
I use a hand file myself. Takes a few minutes to get a blade back to fighting weight. New files obviously work faster than older dull ones. I can pull a file from the tool box, few slaps on both sides and I'm done. Not looking for shaving sharp blades here. Just a good bevel clean up.
No reason to fire up some super expensive electric grinder. These are lawn mowers, not the space shuttle (Taryl). I can have a blade sharpened roughly in the same time as pulling a grinder out and plugging it in. Look at the bevel, set your sharpening angle and finally remve TOO MUCH material. Now you are into balancing for quite a while...... And your blades all have smiles to them now compared to simple hand files. More grinding to correct the smiles. Now you've just removed a bunch of life from that blade.
Summation, you burn through blades a lot faster with grinders than with hand files. Most people don't even check for sharpness when done. They see a shiny new bevel and think the blade is sharp.
I use a hand file myself. Takes a few minutes to get a blade back to fighting weight. New files obviously work faster than older dull ones. I can pull a file from the tool box, few slaps on both sides and I'm done. Not looking for shaving sharp blades here. Just a good bevel clean up.
No reason to fire up some super expensive electric grinder. These are lawn mowers, not the space shuttle (Taryl). I can have a blade sharpened roughly in the same time as pulling a grinder out and plugging it in. Look at the bevel, set your sharpening angle and finally remve TOO MUCH material. Now you are into balancing for quite a while...... And your blades all have smiles to them now compared to simple hand files. More grinding to correct the smiles. Now you've just removed a bunch of life from that blade.
Summation, you burn through blades a lot faster with grinders than with hand files. Most people don't even check for sharpness when done. They see a shiny new bevel and think the blade is sharp.
Hammermechanicman
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Do you run a mower shop?
Most folks on this forum fall into two categories. Homeowners and shop owners. Each will have their own way to do things. Sharpening 150 or so blades with most of them beat to hell with a file wouldn't be profitable. I need to be able to sharpen a 3 blade mower in 10 minutes or less.