Sharpening Brush Hog Blades

[DTCOOPER]

Well, this is assuming that you guys are able to help me get my stump jumper off the deck..
I need some directions on sharloening the blades. They are not in horrible shape, but a few nicks chipped out of the leading edges. I have heard that they are not supposed to be "sharp", but more just "square"..

Can you guys give me some pointers ? I have all tools necessary I believe.. Just lack the know how to get it done..

Thanks again,
Daniel

 

[Brad_Blazer]

Block the mower up when you are working under it.

You should have an access hole in the top to get to the blade bolts. Rotate the gear box by hand until a bolt is aligned with the hole and remove the nut using your 3/4" drive socket with breaker bar. The bolt is keyed so don't let it drop down and skip. I put a jack under the bolt if the nut is not turning freely and the bolt wants to drop. The stump jumper stays in place - you just remove the blades.

Once the blades are off they can be sharpened with any grinder. I prefer a 9" angle grinder.

I have also sharpened the blades by tilting the mower on it's side and leaning it against a post or something to sharpen the blades without removing them.

Make sure the blades end up the same weight and shape for balance. Put them on nice and tight making sure the keyed bolts are aligned properly. I use a 3' cheater.

Grease it and check the gear oil while you are working on the mower.

Here is the KK manual. They don't really address sharpening but there is other good info.
http://www.kingkutter.com/downloads/manRKRK.pdf

Brad

 

[john_bud]

Brad did a pretty nice job. It's preferable to leave the blades on as they can be a real chore to take off. Then again, if you do take them off - be sure to use some never sieze when you put them back on.

I have sharpened blades on the cutter by just lifting it with the 3pt all the way, blocking it with 4 (yes 4) jack stands and 2 6x12x2' blocks of wood next to me. Just in case it drops off the jack stands. A Dremel tool, die grinder or even a file and elbow grease work.

For cutting brush and small trees, you want to leave 1/16 to 1/8" of flat verticle on the "edge" of the blade. The 1/16 is for doing brush and tall thick grass. The 1/8 is for doing smaller trees. Less damage to the blade and more damage to the stump. You WANT to shatter the stumps to keep them from growing back. A sharp cut stump will re-sprout into a cluster.

good luck!
jb

 

[jimainiac]

After taking the blades off, I decided it's a lot easier to sharpen them on the cutter. I raise it up on the 3PH and block it securely, and use a 4 1/2" angle grinder, which is light enough to hold in one hand while steadying the blade. As the others said, there's supposed to be a slightly blunt edge.

 

[woodlandfarms]

So, why not make the blades sharp. I had not heard of this before.

Also, I have used my FEL or Pallets Forks to lift mine up on its end to sharpen...

 

[MrJimi]

So, why not make the blades sharp. I had not heard of this before.

Also, I have used my FEL or Pallets Forks to lift mine up on its end to sharpen...

If the blades are too sharp they will leave a sharp cut and puncture a tire and if they are a little dull/blunt they will bust it up and wont puncture tire

 

[BB_TX]

I don't take anything off. I just chain my cutter to the FEL, raise it up until it is standing it on one side leaning back against my FEL, and have at it with an angle grinder. Much easier to me than having to reach under it. And my blades typically stick to the stump jumper over the winter (pic 2) so I have to free them up and oil the pivot (pic 3).

 

[DTCOOPER]

okay my blades are considerably more boogered up than yours.. Should I just go ahead and change the baldes and start with new ones ?

 

[skipmarcy]

Most blades on 5' & 6' cutters are pretty healthy and can be sharpened many times. Personally I like a sharp edge but at a very steep angle - this gives me the cut I want for my grass plus will shatter larger stuff and hold an edge a little longer. Dings from rocks etc. won't be as deep into the edge with a steep angle too, a little easier to grind out. I use my hyd. toplink to kick the rear of the cutter up high, put a jackstand under it, then clamp a pair of Vise-Grips on the end of the blade and let it rotate against the body to hold the blade while I grind it with my 4 1/2" grinder. No need to try and balance your blades with just a simple sharpening, if you have to remove enough metal to throw your cutter out of balance to where you can detect it, it's time for new blades !!!

 

[BB_TX]

My blades are not quite as nice as they appear in the pictures. They have been sharpened several times. But they are so heavy that I don't think that occasional sharpening is having much affect on the balance. If I have to grind one to get a notch out, I try to grind the other an equal amount. I figure when I start to notice some vibration, it will be time to get new blades.