Rotary Cutter Rotary Cutter

JimMorrissey · May 18, 2004

Bought a 4' rotary cutter for my BX the other day ($450). It has no names on it at all, but looks just like a bush hog.

My question is....do all brush cutters / rotary cutters vibrate and make loud noises while just spinning (not mowing)? I have to wear ear protection while using it and it shakes the whole tractor. I have a feeling the Woods version doesn't do this. Basically, I'm wondering if they are all crude bashers to be used the least amout possible....or did I get a homemade, out of balance piece of junk? --It destroys almost everything it hits, including some descent sized small trees without much problem...It's just very, very crude.

Thanks,

Jim

Laminarman · May 18, 2004

Hmm. I start up my 6' Land Pride and it wobbles my TC40DA quite a bit for a second, but then when she's humming after a few seconds (about two), the whole thing just hums and whirs. I did have an incident when it banged the tractor around and the blades got crossed underneath. Check the blades, preferably with the PTO and tractor off. /forums/images/graemlins/tongue.gif..good luck

wisconsinguy · May 19, 2004

hi

I have a 4 foot John Deere cutter on a 2210 and it is very quiet, can't really hear it run. It does shake for a few seconds till the blades are straightened out but after that it is real smooth. I'd take a look underneath, the blades should move, maybe one is froze up or bent or something.

Phil

KiotiJohn · May 19, 2004

Jim there are a few reasons for the wobbling. My first choice would be that the blades are not balanced. One may be well cut down and lighter than the other. Also a bent shaft would cause it. One could still cut with it depending on the amount of bend, but it would wobble. It could also be that somethingn is simply loose. If you have not done so, make sure you go through ALL the bolts and assure that they are torqued well down as the blades can come flying off and do a lot of damage, even death. Lift the mower into the air and turn off the tractor. Reach under and carefully inspect the blades, turning them by hand to see if there is any bending to the shaft. Look for chunks of metal that may have been broken off causing out of balance blades. It's not unusual for a well used brush mower to not have been cared properly for, and wobbling is common. Just make sure everything is right before using it again. It may save your or someone else's life. John

Soundguy · May 19, 2004

My brush cutters wobble a bit as they spin up.. but are otherwise fine when running at full speed.

Lif that cutter up with the 3pt, and then block it there.. disconnect the pto shaft and let it hang FREE

Observe the blades on the stump jumper. They will need to be able to pivot on that stump jumper. I've seen some blades rusted in place where the blades did not stand directly out from the stump jumper.. and when they spun up.. were of course unballanced.

If that is your case.. hit them with some pb blaster.. and then give them a good whack on the back side and get them to lossen up so that can swing straight out. Also.. measur ethe blades tip to bolt on each side.. make sure you havn't lost a blade tip. Also lok the blades over.. if one is worn down to a nub and the other is new.. that will unballance them. These aren't ginsu knives and don't need to be 100% same weight etc..You will always get minro imperfections between the two when hitting rocks.. etc. but the closer they are.. they better they feel running.

Some go to the trouble to remov ethem and weight them and grind them down to match.. While I'm sure this gives you a grat ballance.. I think that it is more or less 'lost' time and diminished gains... for one.. you are probably grinding off excess metal, and that will prematurely age the blade.. and two.. It isn't a 10 minute job either... like I said.. these aren't scalpels.. mor e like a swinging axe. Just get them safely on there, and real close to the same size, and go with it.

Also observe the stump jumper.. make sure it doesn't wobble or have a huge dent in it.

Soundguy

OkieG · May 19, 2004

do all brush cutters / rotary cutters vibrate and make loud noises while just spinning (not mowing)? 

No. Should be just a whirring sound of the blades spinning through the air, with little or no vibration. Good advice from KiotiJohn and Soundguy.

OkieG

BB_TX · May 19, 2004

After several years of cutting brush, deadfall, and hitting stuff that washed out of the creek, mine vibrates more than when new, but not enough to be of concern.
Soundguy give very good advice on making sure your blades are loose. This is essential both for balance and to make sure the blades can absorb the shock of hitting objects, rather than transfering that shock to your PTO shaft.
Each spring I pull my tractor up to the side of the cutter, securely attach a chain from my FEL to the opposite side of the cutter and raise it up until vertical but still setting on the ground. Then I back up just enough to the cutter leans back toward the tractor. That way I have safe access to the full underside of the cutter without having to crawl under it. I make sure the blades are able to swing freely, and if not, loosen them. The blades should be free enough to hang straight down when the cutter is turned up like that. Then I put some heavy weight oil or gear lube on the pivot pin. Once a season is all it needs. I can easily sharpen the blades while I have it up.
Make sure your gearbox is tight to the deck or tighten it while you have it up.

KiotiJohn · May 21, 2004

( Observe the blades on the stump jumper. They will need to be able to pivot on that stump jumper. I've seen some blades rusted in place where the blades did not stand directly out from the stump jumper.. and when they spun up.. were of course unballanced.)
Great suggestion Soundguy. I hadn't thought about that even though I experienced that situation many years ago. Too many years ago!! John

JimMorrissey · May 22, 2004

All,

Thanks for the input. I will check the blades. For the record, it's new so the blades are not out of wack. They may not be tightened enough though. I'll take a look. Frankly, I think I'm just mad that I didn't spend the extra $450 and get a real Woods attachment! I'm now hyper-sensitive to any problems with my new "junk". I never buy junk.....Not sure why I bought this. It's just not the finely machined piece of equipment I envisioned; however, it does work and work well. You wouldn't believe the "brush" I cut to pieces. It's amazing what the thing with destroy. Basically, anything the BX can drive over, it will cut up....I'm talking 1.5 - 2 inches in diameter.

Jim

KiotiJohn · May 24, 2004

( Basically, anything the BX can drive over, it will cut up....I'm talking 1.5 - 2 inches in diameter )
Jim, I respectfully suggest that when you're going to cut anything over 1" in diameter with that mower that you slowly back into it, let it cut a little, back again, until you've cut it down. That mower is most likely rated for 1" material and just simply running right over it and cutting it all at once may damage the mower. You'll be pleased with the results, and I've cut up to three inch doing it this way with no damage to the mower as I'm only really cutting a little at a time. John