Rotary Cutter Rotary Cutter Design

[paccorti]

I have a Woods XT172 (72") light duty rotary cutter. So far I have been pretty happy with it. It is rugged and has even helped break up some rocks! Now here is the question.

I've noticed that some heavier duty rotary cutters have chains in the back. My XT (and many other rotary cutters that I've seen) has a solid metal flange that goes all the way down in the back. I assume that this is to keep material in the rotary cutter so that it gets mulched up even more. This works fine unless the grass is so tall that you end up with a LOT of grass confined under the deck. For example, today I was cutting 3' high wet grass. Then my TC35 started to bog down (I have the cutter set on the lowest setting 2" cut height). While moving forward, I picked the cutter up with the position control and was astonished at the HUGE amount of grass that dropped out of the cutter. No wonder it was slowing down. If the material could get out the back then the grass wouldn't bog the tractor down. Chains in the back seem to have another advantage. When backing up to cut, the flange severely pushes down the grass before the cutter has a chance to cut it. Perhaps there is some disadvantage to having chains in the back.

Now of course I could raise the cutter up (which I did). Unfortunately, this means that I'm not cutting as low as I would like (2nd pass required). The tractor can cut the grass, it's the accumulation of grass under the cutter that is causing problems. Thoughts anyone?

Peter

 

[geneP]

I don't know the answer to your delima, but I had a John Deere model 606 that was like your mower. If I kept the tail wheel dropped so the rear of the mower would ride high, it was ok. But I like to keep mine more level for a better cut in grass. I also bent my skirting on the rear next to the tail wheel when I would try to back up close to trees, etc, for closer trimming. I finally cut a portion of the skirt off the back to let the grass out. It probably increased the possibility of objects being thrown, but I'm in a rural area and it's not a concern.

A year ago I traded down to a smaller tractor and got a new cutter with an opening at the rear. This one is designed better for my needs, and cuts really good in clean grass.

 

[mikim]

I've got a Woods 600 - they call it a medium duty but it sure is heavy enuff for my TC45 - anyway - I bought chains for it and replaced that flange with the chains. (The chains are not standard on cutters - ya gotta buy 'em extra.) Took me about 5 minutes - the chain guards bolted into the same holes that flange came off from. Just FYI --- if you felt chains would work better for you - you could check with Woods or your dealer about a set for your cutter. I like 'em for what I do. I'd probably have that flange bent by now. I lower my cutter down onto brush sometimes and the flange might've caused a problem doing that.
mike

 

[radman]

Most rotary mowers have either a metal flange or chains in the rear to deflect flying objects hit by the blades. People have been severely injured or killed by flying debris. In general, it is cheaper to put on a metal flange than chains for a deflector. I am not sure which one offers more protection. Chains tend to hang lower, but a metal flange may deflect material better. Some manufactures also put chains in the front of the mower to stop debris from flying out as well. I have heard of tractor tires being punctured by debris. As far as mowing your grass, it definintely will mow easier, put less stress on the tractor and do a much better job when mowed dry than wet. I wait for the grass to dry unless in a hurry.

 

[JimBinMI]

Paccorti,

I have the Woods XT148, 48" rotary cutter on my TC18. Isn't the metal "flange" that you're talking about actually part of the deck and not an attachment? If you cut away part of it and replaced it with a chain, wouldn't you be jeopardizing the integrity of the cutter? I'm not saying that you suggested doing this but some of the responses were sounding like this.

I have my rotary cutter set at about 6", right in the middle, but I'm thinking of moving it down to 4". I only used it twice last fall but never had a build up problem cutting 2'-3' tall grasses. Thanks for the heads-up that if I lower it I may have to dump the build up once in awhile. My field needs mowing really bad but we've had so much rain and with other things to do, the field is getting tall again.

I do have a chain on the back of my Woods 60" finish mower and feel good with it there as a guard. I don't seem to get too much build up on this mower either.

Good luck, JimBinMI

 

[DaveM]

Peter- I have a Bush Hog SQ600 cutter with a metal rear deflector and haven't yet experienced a build-up problem. The owners manual describes how the cutter will perform with different adjustments and this may help your situation. It essentially states that cutting will be easier if the rear end of the cutter is 1"-2" higher than the front, allowing more cut material to exit easier. As you raise the front or lower the rear to make the deck level or higher in the front you'll get more mulching action because the material is held under the deck longer. Maybe this is what's happening with your cutter and the way you have it set-up?

Good luck!

Dave

 

[Harv]

I installed chain guards on my 60" cutter, as pictured here, before I ever used it. It certainly gives me some peace of mind when I'm blazing away out in the back boonies of my property. Rocks seem to appear out of nowhere, even after I've cleared the areas once. Must be rock fairies or something. /w3tcompact/icons/crazy.gif

I believe the choices for my cutter were a rubber flange or the chains. Don't recall seeing the metal flange as an option, but I may have just missed it. I like the way the front chains glide easily over small obstacles while still offering kick-back protection. Seems like I'll be able to set the mower lower (haven't tried it yet -- I'm still chicken), than if I had a rigid set front/rear guards. Just newbie speculation, of course.

As for the grass build-up, Peter, I was wondering just how green/wet your grass was. I can see the wet stuff clumping up, but hard to imagine the drier clippings causing a problem.

 

[patton]

Where did you get the chain guard from? It looks pretty generic, in that it could be modified to fit other tractors.

Pat

 

[Harv]

Pat -

I just called my (not so) local dealer, gave him the make and model of my cutter, and he did the rest. I dunno about them being all that generic. The front chain bracket needs to be the right width and then it's just a matter of matching up bolt holes. But the rear chain bracket conforms nicely to the exact shape and dimensions of my particular cutter.

You may be set up to modify stuff like this, but for $185, I'd take a shot at finding the right ones for the job. /w3tcompact/icons/crazy.gif

 

[patrickg]

I have a 3ph mounted 6 ft super heavy duty rotary cutter/mower/brush hog. It has chains in the front and back, a single centered tail wheel, and a large "stump jumper cenral disk". HP requirement is listed as 40 to 75 at PTO (my 39.5 seems to be enough but not likely to break it) A neighbor (Superman ingognito I think as he is in late 60's and puts in 12-16 hrs 6-7 days a week A N D knows more about cattle and implements than the law alows) showed me that when cutting tall or wet grass that he tilts the front of the cutter down a bit and raises the back a bit. Then the front height determines the height of cut and the raised back eases the discharge of accumulated mulch. He also doesn't do this anywhere near people, stock, or anything that could be damaged by 150 mph debris since with the rear elevated it could more easily spit out something. With my brush hog level but set to cut about 6 inches high or so, I've thrown 1 1/2 in to 2 in sapling trunks over two feet long out of mine as far as 30 feet or so (maybe farther I can't dodge the big trees and look backwards at same time. When I run over a "bigun" it really slows me down and the whole rig shakes and jumps for a while as it chews it up and spits it out. I am trying to train myself to let up on the hydrostat pedal as soon as the rpm starts to drop much as rpm is what the brushhog needs to cut cleanly and discharge the cuttings. Remember to not sharpen the brush hog blade to a fine edge. I was told to sharpen it as if tapering to a fine edge but leave the actual cutting edge blunt. I'm told this helps shatter woody stems and that they decompose better and aren't little punji sticks.