Rotary Cutter Sharpening the blades

[LouNY]

My old Woods brand has never been sharpened, it's hit an unknown number of rocks and other debris.
The blades have a rounded over profile they work good for what she is used for brush and large course weeds.
In pastures and fence lines stone walls and such, we have many other mowers suited for grasses from sickle bars to haybines and discbines even a flail.

 

[JasperFrank]

At the start of the season I use my FEL to pick up and completely flip the Brush Hog on to its back. Then use an angle grinder to put a LIGHT edge to the blades. Then check the tightness to all the nuts and bolts and straighten up the skirts. To me, this seems the safest way of doing it and I can inspect everything clearly.
I have heard from many other people that blade sharpening was not necessary, if your use is to take out brush. But at the start of the season, sometimes the grass areas are still wet, and have gotten higher than the lawn tractor mower can deal with. The sharpened blades do a much better job on the tall, wet grass than if they are blunt edged.

 

[Tony H]

I sharpen mine every few years. Just an angle grinder works. I like to CUT not TEAR, what I'm going thru. It makes it easier on the PTO. Angle grinder works since balancing the blades aren't a real issue

 

[ROUSTABOUT]

I've had them sharpened down old blades. Welded a piece of road grader blade on them and were like new again. Hung them on cotton scales to get them weighing the same for balance.

 

[beenthere]

I have a 6" rotary cutter I have used for years to clear some old pasture. Like many of us I have hit a few rocks and some branches along the way. All of that being said the "sharp side" of the blades now have a bullnose profile. I have never sharpened the blades.

I went by a local shop and asked about sharpening the blades. The first fellow I spoke with looked at me like I was crazy; he said he'd never heard of sharpening the blades on a rotary cutter. The second fellow interrupted him and said they did sharpen the blades. Since I have never sharpened them they still have plenty of width.

Have you ever sharpened your bush hog blades?

How do you know when they are not worth sharpening?


My plan is to by an extra set of blades to replace my used blades. I will then have the used blades sharpened and keep as extras. Any advice?

No problem with you spending your money on new blades. But not necessary, just that it will make you feel good.
If using the rotary to cut brush, your present blades will likely do that very well. If trying to use the rotary mower to manicure to a lawn-like finish, then the rotary mower is the wrong attachment, IMO.
As many posts suggest, touch up any rough spots with an angle grinder.
A photo of your blades would be very helpful to zero in on better suggestions for you.

 

[10backacres]

If memory serves me you need a troque multiplier to remove the blade bolts. I haven't sharpened my very abused 430. I just use the seppi flail as long as there's nothing really large in the brush

 

[ROUSTABOUT]

Oh no, that was back 40+ years ago when I was a teen! I remember reading it and showing my dad it could cut hay.

I did find this that may help you, Hercules Service Parts - Agricultural equipment repair located in Minden, Louisiana - Your Rotary Mower Experts!

Yep some cutters you could un bolt one side and take it off to cut hay.

 

[ROUSTABOUT]

If memory serves me you need a troque multiplier to remove the blade bolts. I haven't sharpened my very abused 430. I just use the seppi flail as long as there's nothing really large in the brush

I use a 3/4 or 1" impact mostly. There's always the cheater pipe for when using hand tools. Had a fella bring one here needing help getting the blades off. They were left hand threaded bolts. Got to watch out for that too.

 

[mjonesnh]

Have 2 sets of blades. Just changed out dull set on cutter for sharpened set. Will sharpen dull set before end of next season and repeat next fall. Using Makita 3/4 battery impact on nuts. About a 30 minute job for changeout.

 

[Lineman North Florida]

A rotary cutter with a higher blade tip speed will also cut better, as well as getting RPM's up on the tractor so the PTO can get that blade tip speed up where it should be for optimal cutting. I have seen some rotary cutters with higher blade tip speed outfitted with lift type blades that were sharpened give a really good looking manicured type cut on a field, not finish mower look, but close.