Rotary cutter blade pics, advice?

[Bullwinkle123]

I've read the various threads. I know we don't want them too sharp, that dull blades are arguably fine.

After my first field clearing I thought I'd just touch up some rough spots with a file, but man, these look more like they need to be put on the anvil and hammered out. Normal? Just leave 'em alone?

The field cutting definitely seems sub-par now compared to when the blades were new. Pics are of new blades after about 15-20 hours of use.

 

[Roadworthy]

My rotary mower blades are ugly, too. I've used the mower for sixteen seasons and never sharpened the blades, even after the occasional rock. I don't cut my fields to be pretty, more for wildfire prevention. If I wanted a nice even cut I'd probably have a finish mower. You won't touch your blades up with a file - you'd need a grinder. I'd just leave well enough alone.

 

[deserteagle71]

The blades on my mower look MUCH worse than that. I've been using it mowing desert (lots of dirt mounds from ground squirrel and badger burrows) for the past 22 years and the blades have never been off and never sharpened. One of my projects for this coming winter is to see if I can replace the blades - I'm afraid they are getting to the point one of them might disintegrate - but I'm not sure if I can get them off. May have to use a cutting torch.

 

[/pine]

Just guessing from the pic...but it looks like the blade edge has lost some temper...possibly from heat generated by grinding ??

 

[jaxs]

Piney is right,from the way blade edge is bent,the metal is soft. The blade also appear's much thinner than usual. I wouldn't sharpen that blade but I'd certainly compare thickness to other mowers and take note how blades normally wear and chip but don't distort.

 

[Bullwinkle123]

Just guessing from the pic...but it looks like the blade edge has lost some temper...possibly from heat generated by grinding ??

Nope, that's a brand new blade with its first season in my field, untouched by me. The damaged edge is _very_ thin in places now, I don't know what it looked like new, I didn't bother to see.

The only grinding it's had is the the occasional rock in the field.

 

[MF243RedTop]

That's a lot of rock grinding right there, whether you hear it or not from the seat.
Can you get a pic from above or from the end of the blade edge? That will help in determining what's left of them.
I use a 7" grinder on mine.

 

[oosik]

Odd, very odd. I can see by the posted picture that Bullwinkle's blades are MUCH sharper than the OEM blades on my cutter. My blades have 48 hours of use.

Mine are blunt, quite a bit thicker and sharpened at a much steeper angle.

 

[Bullwinkle123]

I'll see if I can find a picture I took after only about 2 hours last spring, though it wasn't very good, maybe it will show more about the original blade shape.

I'm wondering if perhaps they're in worse shape because my blade is angled too steeply forward. If I recall correctly they recommend only an inch in height difference between the rear and front, it's quite possible mine is more than that and that I need to take the rear wheel adjustment so that the deck is down a notch.

Still, seems like that would have had to have been a _lot_ of grinding, and not just the occasional blade hitting the crown of a rock before the jumper gets to it.

 

[ovrszd]

Nope, that's a brand new blade with its first season in my field, untouched by me. The damaged edge is _very_ thin in places now, I don't know what it looked like new, I didn't bother to see.

The only grinding it's had is the the occasional rock in the field.

I'm with Pine. Exception being, I don't think that blade was ever properly tempered. What brand cutter is this?