Should I sharpen my brush hog blades?

[PaulL]

I hear lots of people with stories about how you should sharpen the blade then blunten it a bit, or not sharp it until it's all the way sharp.

I have a pretty simplistic view on this, because I beat on my mower pretty hard mowing roadside. So it mows a bit of gravel, the occasional stone and stump, sometimes bottles or roadside trash. It's a fact of the terrain I'm mowing. It means I sharpen quite frequently.

My view is that I sharpen them to sharp. Not crazy sharp, but till it has an edge. 2 minutes after I start mowing they'll be about as blunt as people recommend, because my blades are self-blunting. There's no need to manually blunt them, it's more that you shouldn't take them off every 5 minutes to try to make them sharp again.

I sharpen about once a month, sometimes two months in winter when I mow less often. They're pretty blunt when they come off.

 

[D2Cat]

PaulL, I agree. The concern is if the blades are sharp they can leave stobbs that can split a tire. In the fields I mow I spray and remove all small growths before mowing, or mow around them and get them later. I could actually use a different style mower just as effectively, and do some times.

 

[capngeo]

My father in law always had his brush cutter blades sharpened by his local blacksmith shop. They would reshape them back to new looking without removing any metal. He had three pair and would take in two pair for sharpening at a time. I was amazed at the quality of the blacksmith's work. He told me the cost of having them sharpened was very reasonable. The blades lasted and were never replaced, until the deck on his cutter finally rusted away and he replaced it.

I agree that in a perfect world, this is the way to go! BUT.... (there's always a BUT) in the real world, unless you just finish cut lawns your blades will look like this:

Disclaimer: I am a professional, my company mows thousands of acres a year, and the above blade has less than 40 hours on it.

We have an Atlas Mill:

We set up a tilt table on it, set to 37.5° and mill back to this:

Sometimes it takes a bit of welding for the bigger gouges like the one in the first picture, but the end result is a "new" edge that can be field dressed with a 4" grinder on a daily basis. We do that for 40 hrs or so, then back to the mill. We keep 5 or 6 sets of blades in reserve, and once the mill is set up, it goes pretty fast. 5 sets of blades will last a couple seasons (I'm in Florida, we mow about 9 months a year)