New Rotary Cutter Blades... (sharpen before use or not?)

[RJI]

Just had to buy new blades for my Land Pride RCR 1548 cutter... my question is, Do I need to sharpen these before use?
they appear not to have any area that has a sharpened edge, but a rounded edge...
These are OEM blades for this cutter right from the Kubota dealer...

thanks in advance...

 

[bcp]

A blunt edge is generally preferred unless you are only cutting grass.

Bruce

 

[Cougsfan]

BCP is right. I have worn out rotary mowers without ever sharpening the blades. On weeds, the blunt bade shatters the weed and makes it more apt to die. If you are cutting grass for aesthetic purposes, you probably should be using a lawn mower, not a rotary cutter.

 

[xrjohndeere]

Just had to buy new blades for my Land Pride RCR 1548 cutter... my question is, Do I need to sharpen these before use?
they appear not to have any area that has a sharpened edge, but a rounded edge...
These are OEM blades for this cutter right from the Kubota dealer...

thanks in advance...

Sharpen if you want. After a few hours of brush hogging they will be blunt. If your just mowing grass and pasture put a edge on them. It will cut cleaner and be less damaging to the grass.

 

[WranglerX]

Almost every article I have read recommends blunt edge on blades.... Even on my riding mower blades are not "sharp"... Factory edges on blades should be correct for use...

 

[oosik]

I have a set( three blades ) of new blades for my JD X570 riding mower. They are blunt. I will first try try them as-is. I cut about two acres of meadow grass - my "lawn". Hopefully they will be fine without sharpening.

"Blunt" is a relative term here. The new blades are tapered at the cutting edge. They are not razor sharp - not as thick as the remainder of the blade.

 

[livemusic]

Opinions vary on sharpening rotary cutter blades. If you favor sharp, I have read that you should not sharpen to a razor edge like a knife, that the blade will tend to chip/break chunks off, that if you sharpen them, leave a square edge that is 1/16" thick. I am in the camp that if you are cutting brush/saplings, blunt is better. If you're cutting/mowing grass, a sharper edge is warranted.

As for a lawn mower mowing grass, I am amazed when I install new blades with a good (relatively sharp) edge on my eXmark zero turn, they cut/mow so well!

 

[Beaver Cove Deere]

Lawn blades are sharp. Brush hog blades start that way but don’t count on keeping that edge.

I’ve bought at least a dozen sets of blades over the past 30 years cutting a field that contained a few “rocks”.

 

[IndyJay]

When I "sharpen" my blades, I am mainly taking out the dings. If there is a keen egde when I am finished, I take a flat bastard to the edge to "square it up" to about 1/16 for lawn mower, 1/8" for brush mower knives.

 

[Lineman North Florida]

I want my lawn mower blades as sharp as I can get them, bush hog or rotary mower I don't worry so much about, I will only hit them with a hand grinder every other year or so.