Opinion on to sharpen or not to sharpen a brush hogs blades

[Johnp33]

I was taught the blade should be ground down till there is about a 1/8 to 1/16 original edge. Grind the bottom flat to remove the dings.
I have a balance tool for lawn mower blades, it was cheap, it has different sizes in a cone. Balance is very important.

 

[Geneha]

My Rhino Bush Hog was about 10-12 years old and had the original blades when I got it (July 2012). I noticed what you are talking about in that there was a fair amount of vibration. Pulled the blades off and first thing I noticed was the blades are dull and wanted to sharpen them up like my regular lawn mower blades. Wrong. Bush hog blade need to be for lack of word like to be dull or have a kind of rounded/squared edge. This how a bush hog can chew up thick tall stuff. I noticed that the blades on the ends where rounded off and squared. I, at this point decided to purchase a new set of blades and boy what a difference. The vibration is all but gone and the new blades where about 1/4" wider at the cutting edge and the ends where squared. Boy this cuts and runs so much better. I weight the old blades and they was a fair weight difference which caused the initial vibration. Next to remount the blades, in the garage I lifted the bush hog up all the way and when I put the blade and bolt back on I just used a car, floor, piston jack and held it in place until I could get the nut almost tight. This made a one person job of changing blades easy.

Hope that helps

 

[new jersey mike]

I have a 50 year overgrown farm with some hayed fields, That day I was just cutting an area to park my jeep as a staging area, other days I am testing the limits of the mower with well overgrown trees. Usually I will have my 6ft bucket on to match the width of the mower. if I am in a willow brush area I will back over them starting with the deck raised and dropping down. I go backward for that because how far the branches stick out and will hit my face. Other times it's mower assisted with chainsaw, I will walk the tree edge cut larger trees and pull them out and roughly pile them up, this way I can make 1 or 2 cuts and then repeat cut and mow. Then put the grapple back on at the end of day and move all trees to a central brush pile(s).

Project varies from widening fields, cutting pastures at the end of season, opening up old log skids, etc.

I will actually miss the heavily overgrown areas, this was all new to me with a major learning curve. Nothing is flat or super easy. This year because of the drought I have been able to mow in what is normally wet with no worries of getting stuck.

I really do enjoy doing the work.

From the debris underneath, looks like you are cutting lots of fine grass. I would sharpen and the angle of the blades to be dependand on how confident you are that you've gotten the rocks. Sharper and more of an angle if you're confident, less sharp and an angle closer to square if not.

I think you can obtain a reasonable approximation of balance, once the blades are off, by bolting the two blades together and trying to use the bolt as a pivot, or better yet, using a piece 1" pipe or larger (fully threaded, short nipple) with a couple of fittings on each end to serve as nuts to cince down and keep the blades straight. Then balance on your fingers or a rod, stake, whatever that will fit through the hole.

 

[cmore]

Sharp blades require a lot less HP, while they are sharp. But they don't stay that way long. I don't like sharp blades in brush as they tend to cut the saplings so a sharp point is left and that makes it easier to run a stob into a tire. So only sharpened, occasionally, like only every 10 years or so :>).

For grass cutting, a sharp blade is better otherwise would recommend dull.

 

[DKCDKC]

I cut both grass and brush with my Howse cutter. I've had it 11 years and have sharpened it about four times. I sharpen it by hand with a hand grinder to about a 1/16 inch blade edge. I don't worry about gouges and such, and they seem to affect nothing. I did take the blades off a year ago when I noticed some vibration. I balanced them with a homemade balance scale and used the grinder to take off weight. The vibration went away completely. The comments here on really sharp blades are on the money. Too sharp and it will leave sharpen stubbs that are hard on the tires and on people.

 

[TripleR]

From my Land Pride RCR2672 Manual:

Both blades should be sharpened at the same angle
as the original cutting edge and must be replaced or
re-ground at the same time to maintain proper
balance. The following precautions should be taken
when sharpening blades:
a. Do not remove more material than necessary.
b. Do not heat and pound out a cutting edge.
c. Do not grind blades to a razor edge. Leave a blunt cutting edge approximately 1/16” thick.
d. Always grind cutting edge so end of blade remains square to cutting edge and not rounded.
e. Do not sharpen back side of blade.
f. Both blades should weigh the same after sharpening with not more than 1 1/2 oz. difference.

 

[wedge40]

I also have the SQ172 and have taken the blades off, with the help of buddy and 6' breaker bar (aka pipe). That was just to get the nut loose, then I had beat the bolt out of the hole. It's a tappered keyed bolt. From my understanding the nuts are torqued to 650ft/lbs. I ended up getting a 3/4" air ratched to get it back on. If you're not ever going to cut brush with it you I'd say it's ok to put an edge on it. But if you cut small tree's etc, you want the blade to be dull so it shreds the tree and dosen't cut it. If it cuts it, it leave behind a small sharp spikes that aren't good for tires. When I need to do mine again I will take them off.

Wedge

 

[Domush]

d. Always grind cutting edge so end of blade remains square to cutting edge and not rounded.

Anyone know the reasoning behind this? Not that it matters much, I guess, as a few rocks later and they are rounded again

 

[LD1]

I have a balance tool for lawn mower blades, it was cheap, it has different sizes in a cone. Balance is very important.

I have one of those, and they work great for FINISH mower blades. But with bushhog blades, the hole is at one end. How do you manage to get that thing to work with your bushhog blades:confused3:

I pretty much will echo what others have said. I dont worry too much about balance. Just grind about evenly on both and be done. These blades dont turn near the RPM of a finish mower and they have MUCH stouter bearings.

And ditto what others said about not making them razor sharp. For general brush clearing/bushhogging, you want a semi-blunt edge like others mention. BUT, if you use this bushhog for just cutting pasture grass and weeds every month or so, and sapplings dont have a chance to grow, razor sharp WILL leave a better cut and at a faster pace. BUT...not by much. There isnt a ton of difference. But unless this is the case, leave them blunt.

Also....saftey note, if you leave them on the bushhog and no it from below, dont rely on just the 3PH to keep the mower up. Block it up with something in the even the hydraulics fail or something.

 

[TripleR]

Anyone know the reasoning behind this? Not that it matters much, I guess, as a few rocks later and they are rounded again

Beats the heck out of me, I just do it religiously ever two, three, four years or so...

I actually use to sharpen fairly often, but couldn't tell much difference.