Rotary cutter VS flail mower

   / Rotary cutter VS flail mower #1  

Tractor Nubi

New member
Joined
Oct 3, 2006
Messages
13
Location
Victoria, BC
Tractor
Dong Feng 354
Have a rear mounted rotary cutter and it continually gets bogged out on long grass. It wraps around the part that holds all the blades. I am sure I am not using it correctly. Wondering if a flail mower would be a better investment. I see the city mowing down the country road edges with a rotary mower on an arm and they do not seem to get wrapped up. Any help, suggestions or videos would be appreciated.
 
   / Rotary cutter VS flail mower #2  
I was thinking the same thing. I use a rotary brush hog at my sons place and end up shearing a pin every few hours. Go over some uneven ground and its back to shed for repairs. Thinking for my use I would like a flail mower better, seems like the rotary is the standard, why.

HS
 
   / Rotary cutter VS flail mower #3  
Sharpen the blades if they are very dull. Run the tractor at an rpm such that the rear pto rpm is correct for the mower (1000 or 540). Keep the ground speed reasonable. Maybe you are traveling too fast.

A rotary mower is just a rotary scythe with a dull blade. A flail mower is a impact hammer chopper. Lots of little wackers hitting a steel roller with grass weeds, stones, wire, bricks, animals and toys being bashed to pieces.
 
   / Rotary cutter VS flail mower #4  
Sharpen the blades if they are very dull. Run the tractor at an rpm such that the rear pto rpm is correct for the mower (1000 or 540). Keep the ground speed reasonable. Maybe you are traveling too fast.

A rotary mower is just a rotary scythe with a dull blade. A flail mower is a impact hammer chopper. Lots of little wackers hitting a steel roller with grass weeds, stones, wire, bricks, animals and toys being bashed to pieces.
:confused: The flail knives or hammers [different] are pivoted from their attachment point on the steel "roller". This rotor spins very fast and the knives are held straight out from it by centrifugal force. The knives dont hit the rotor unless they are flung back against it by encountering something hard.
larry
 
   / Rotary cutter VS flail mower #5  
LIke has been said. If you are bogging down...

1. Blades are not sharp
2. Not enough HP
3. Too much cutter for the tractor (not enough HP)
 
   / Rotary cutter VS flail mower #6  
LIke has been said. If you are bogging down...

1. Blades are not sharp
2. Not enough HP
3. Too much cutter for the tractor (not enough HP)

X2.

i used a 5' brush cutter for several years to mow rough vegetation and up to 2" thick tree regrowth on my farm
that stuff grew as thick as hairs on a dog.
Never bogged down or broke a shear pin.
had a 80 hp tractor driving it
 
   / Rotary cutter VS flail mower
  • Thread Starter
#7  
Thank you for all the replies. I have obviously used the wrong terminology and ZZVYB6 has done a great job of clarifying. To summarize, I have a rear mounted flail mower that I am running at the correct speed and rpm but the grass is tall enough that the tractor pushes it down and then the flail is trying to cut the flattened grass. When the city uses them they have them on an arm and they are not 'pre-flattening' the grass. I am looking in to getting a rotary mower instead. My questions are:1. in long grass and up to 1" dense brush is it better to start with a rotary mower and then move to a flail mower when it is knocked down or the other way around? 2. should I just make multiple passes and lower the flail each time? 3. are there videos on how to do this correctly?
 
   / Rotary cutter VS flail mower #8  
Thank you for all the replies. I have obviously used the wrong terminology and ZZVYB6 has done a great job of clarifying. To summarize, I have a rear mounted flail mower that I am running at the correct speed and rpm but the grass is tall enough that the tractor pushes it down and then the flail is trying to cut the flattened grass. When the city uses them they have them on an arm and they are not 'pre-flattening' the grass. I am looking in to getting a rotary mower instead. My questions are:1. in long grass and up to 1" dense brush is it better to start with a rotary mower and then move to a flail mower when it is knocked down or the other way around? 2. should I just make multiple passes and lower the flail each time? 3. are there videos on how to do this correctly?

From THAT description (not your first post) I would guess that you have the front of the mower too low to the ground, i.e. maybe you are just "dropping" the 3 pt ?

I run with the top link in the "freedom slot" and lower the 3pt to a position I know will put the top link in just about the middle of the slot when level, then I watch it once I've started mowing on flat ground and make minor adjustments if needed.
I should add that this is with my hydraulic top link fully extended, which isn't a precise calibration that you can use - the point is that you want the front edge of the mower deck UP off the ground a bit so that it doesn't flatten the grass.
It will still bend it over, but in a gentler arc and the knives will be able to get it on the arc.

After that - KEEP it short.

I think the HUGE thread on "Lets talk flail mowers" covers this somewhere - heck it covers just about everything ELSE in life (-:

EDIT:
You might assume that you can't solve the problem you described by running backwards due to the rear roller having a similar effect on the grass just before it tries to cut it.
However, the Caroni flail performs surprisingly well when backing over stubble that just needs a bit more cutting down, also shrubs.
I don't know why this is, it just is.
I have tried running it backwards for some distance to see if it is an effect from running first forwards and then backwards, but it cuts just fine when running backwards for a hundred feet or more - a little odd, but I'm happy with this (-:
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   / Rotary cutter VS flail mower #9  
mowing any type of tall grass or weeds....

keep an eye on engine temp. because of all the tall weeds, there is a good chance you may not be getting good air flow down through radiator and across engine, like you should to keep it cool. also there is a good chance of leaves and cut grass / weeds plugging up the radiator. which also can cause engine temp to go high very fast on you.

even with finish mowers, at times stuff is just to tall. ""being wet"" can also add to needing extra oomph to cut through stuff. so instead of trying to cut the entire width of the mower deck. do half passes or half the width of deck and in some cases, less and some times more. ((takes time to read the vegetation and learn what your tractor can handle, even then there are needs for constant adjusting of speed and or throttle or how much you cut at one time "width of deck".)) granted bigger the tractor and smaller the implement the less doings above. but for me, it is other way around smaller tractor with bigger implement. so i have had to learn what they can do.

tall weeds / tall grass are big culprits of being nice and dry in the top. but soaking wet around the bottom stems and leaves. if you are having problems, cut as high as you can with deck. and then come back in say a few hours or next day. and cut things down lower. that extra time allows stuff to dry out.

another thing, do it granny style. and go into lowest gear your tractor can go. ya it is turtle slow moving. but that may be just what is needed. in order to let the what ever mower you are using, time enough to cut stuff up and get it out of the deck so it can handle the next set of weeds coming into it.

remember you are cutting tall weeds you are not going to get a golf course looking grass afterwards. and if you want a golf course look of grass it takes maintenance and multi times cutting and growing and cutting. and keeping things short to get golf course look. expect that things will look ragged, and rough cut, with piles of cut weeds all over the place. who says you have to cut everything down to 1" off the ground in first pass? some times it takes 2 to 3 times mowing and each time re-adjusting mower deck. to help chop things up into smaller stuff and spread out the cut weed clippings so there is less clumping if you want it that way. but leaving them clumps is not a real big deal either.

to note it, just raising deck all the way up to cut high, does not mean it is set correctly. on some stuff, you also need to change pins / levers / arms adjustments so the deck is up or down more in the front. pending on what you want to do.

on 3pt implements, some times you can adjust the 2 lift arms. of were they attach to implement but most of the time adjustment is done via TOP link. on 3pt hitch and or were the top link hooks up to the implement.

if you want to nock all the weeds down to a point were you can start using finish mower for the area. expect it to take a few passes initially to chop everything up fairly good use a fail or rotatory cutter. and then expect the blotches of cut grass to take some time to sink towards the ground. and having problems initially with finish mower to cut the stuff. other words you just cut down a 5 plus feed weeds. all those leaves and stems have to go some place and until they rot away. the finish mower has to deal with the dead stuff.

if you are not going to start mowing the area with a finish mower. there is no real worry about how the vegetation looks afterwords. i mean it is grown up into tall weeds!!! and most likely will regrow backup into more tall weeds soon enough.

================
misc blah below! / rant. *shrugs* may or may not help you.

one of the reasons why i generally run at about 3/4ths throttle i like to have a little more throttle i can use to get me through the more dense patch of weeds and grass or taller and wetter or combination of them all.

higher engine RPM's result in more RPM's for the blades. and i honestly do not like crawling under any deck to clean stuff out. so if i can have a little freedom of some extra throttle to get me through those rough spots. vs having to get off tractor and clean stuff out of mower deck. *guess which one i will choose*

granted most tractors have a set spot to setting throttle to a given amount to have enough RPM's for the mower deck or PTO. i honestly never had a tractor that had this setting and if it did the gauge or what not was broken. so i have had to learn by feel of tractor, sound of tractor engine, sound of the mower, and paying closer attention to vegetation being cut, along with having a better idea of when it last rained.

yes i do not wear ear protection. nor saftey glasses. the allis chalmers CA is only rated at 20HP, but she be a very old 60 year old tractor. with a little bit of an engine nock in the front, with some leaks here and there. so i am sure she not producing 20hp with full throttle. she might, but i doubt it. with i want to say 59" or 60" belt driven belly mower under her.

i also have spots through the belt shields that i can easily see pulleys for the blades. so i can quickly glance down and see if a blade has stop or is slowing down and belt is slipping across the pulley.

it is rather dangerous tractor to mow with. but it works great for me. and i am rather hesitant to let others on it. till they go through some saftey doings and then questions after words. i know the tractor others do not and some of them saftey features that should be are simply not there.

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it doesn't really matter what type of mower it is, rottory cutter, fail mower, finishing mower. they pretty much as far as i am concerned in regards in how i pay attention to things, and if i make a half pass vs a full width pass of the deck, higher or lower gears about the same. granted things are a tad different and were you need to look / pay attention to, along with adjusting them. but *shrugs* perhaps some of the above, might help ya.
 
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