New lawn mower blades don't seem very sharp

[Donald]

Got a pair of Oregon Gator blades for my Toro Timemaster. The don't seem very sharp. Reading more about new lawn mower blades and it would seem they are properly sharpened to provide 25 hours of mowing before needing to be sharpened. Any sharper and a stone or stick hitting the blade would dull that area quickly.

It seems they would do a better job if they were sharper but am thinking Oregon knows what they are doing with manufacturing lawn mower blades.

 

[jeepman3071]

You don't want them to be razor sharp. If they are too sharp then they dull even quicker. You want them to be "bluntly sharp" if that makes sense. New blades come painted, and when the paint wears off the edge they are plenty sharp.

 

[Klutch9]

You don't want them to be razor sharp. If they are too sharp then they dull even quicker. You want them to be "bluntly sharp" if that makes sense. New blades come painted, and when the paint wears off the edge they are plenty sharp.

Yep, found this out last year when I bought a new Oregon blade. The paint makes the blade seem very dull, but after a half hour or so of chopping leaves the blade had a nice edge to it.

 

[demarpaint]

As mentioned you want them "bluntly sharp." Just make sure the blade/blades are balanced before installing them and you'll be GTG.

 

[joekingcorvette]

Yes, use the new blades right out of the box. I sharpened my blades last year on my rider after 3 years of neglect and I could really tell the difference.

 

[atikovi]

I sharpen the blade once or twice a year on a bench grinder. Probably on the third blade now in a 40 year old mower. Never heard of bluntly sharp.

 

[nomas]

You can't really rate a blade by the number of hours it should last .

 

[Eddie]

I think "bluntly" sharp means an edge has ~ a 1/64 inch edge. This stays much sharper than a knife sharp edge.
That is how my new John Deere blades come from the factory. Ed

 

[demarpaint]

I think "bluntly" sharp means an edge has ~ a 1/64 inch edge. This stays much sharper than a knife sharp edge.
That is how my new John Deere blades come from the factory. Ed

You nailed it. That's what it means.

 

[walterjay]

I use Gators. Use them the way they are.

 

[mrsilv04]

Is it possible that the reason that they aren't so terribly sharp is for liability... because there will always be some idiot who nearly amputates a finger or severs an artery when trying to install them for the first time... and then calls a lawyer the next day.

And the whole excuse would be that "they were much too sharp" to be safe.

 

[Hall]

Something spinning at 3500 rpm will chop grass pretty easily

 

[eljefino]

Imagine the cutting profile of a machete. It's like a little 90 degree turn, a little distance, then an 89 degree turn. Same with lawnmower blades. I had heard 1/16 inch but defer to Eddie.

 

[jeepman3071]

Is it possible that the reason that they aren't so terribly sharp is for liability... because there will always be some idiot who nearly amputates a finger or severs an artery when trying to install them for the first time... and then calls a lawyer the next day.

And the whole excuse would be that "they were much too sharp" to be safe.

You would think, given our society, but it isn't that. There are preferred standards for sharpening mower blades to make them not dull too quickly. Those fancy sharpening machines have a set angle they sharpen the blades to.

 

[WA1DH]

Once I took the blade off my mower to sharpen and then reinstalled. I cut the entire lawn. When I finished I thought the grass looked a little rougher than usual, although it had cut just fine. I then checked and realized I installed the blade backwards and cut the entire lawn with the dull side. 3000 RPM with any half decent edge will cut just fine.

 

[Cruisin'n5thgear]

I have not one but two scars on my fingers ... same finger, both hands, from cleaning underneath a mower deck after sharpening the blades. BAD idea! They were razor sharp and got me good.

 

[sohccammer427]

I've use the Oregon Gator line. G3 and G6 versions. I believe the G6 version has carbide? fused into the cutting edge. You are correct they are not sharp, actually kind of rounded. I'll give Oregon manufacturing the benefit of the doubt on the design. From my experience, they are the best mower blades I've ever used.

 

[spasm3]

Unless there are really bad dings I use a sanding flap wheel on the angle grinder vs a stone wheel. Does not heat up the metal as much.

 

[Cruisin'n5thgear]

Unless there are really bad dings I use a sanding flap wheel on the angle grinder vs a stone wheel. Does not heat up the metal as much.

Me too. I've switched and never looked back. Leaves a much more consistent edge too vs a solid abrasive disc.

 

[bunnspecial]

Me too. I've switched and never looked back. Leaves a much more consistent edge too vs a solid abrasive disc.

Another convert here.

Faster, easier, and as said it leaves a nice edge without anywhere near as much heating as a bench grinder. It's SUPER easy to heat to blue with a bench grinder, which is bad news for whatever heat treatment may be there.

Aside from that, I find it difficult to maneuver blades on the bench grinder in such a way that I'm getting a consistent angle or even presenting the edge to be sharpened the correct direction relative to the rotation of the wheel. I run a wire wheel on the right side of my bench grinder and only have a stone on the left, so that's what I'm always using to sharpen.

At least one of the fancy sharpening set-ups I've seen basically is a jig that holds an angle grinder and the blade, and really just serves as a guide for consistent angles.