Flail Mower Let's talk flail mowers

[Fallon]

8mph is a bit fast for a flail. Most people go around 3 when running a flail. Flails mulch a lot more, so going slower really helps with the quality of the cut & mulching.

 

[DavesTractor]

Hi Guys,
I'm looking at a used 84' Motrim flail mower on eBay. It looks good, knives really good, but the upper hitch is slightly bent down. I'm also looking at a ford 918H eight footer, also on eBay, but it looks like it was backed into something. The roller looks slightly bent.
The allure is that these are both around $1200, and I have to keep about 20 acres of pasture down while we are without cows. Any thoughts? I run a ford 7000 as my mowing machine, it runs a woods 84 and doesn't know it's there. I'm looking for a better finish, with mowing about every 3-4 weeks. Can I run one of these at 8 MPH, or fourth gear on my ford?
Thanks

I would not buy an abused flail unless you could actually test it first. Normal usage of a flail will never bend it. Cracks along welds due to cumulative vibration is normal on an older flail. A worn out roller can be replaced. A bent main rotor is a big problem. I mow at 3-5 MPH with my 10' flail.

 

[Code54]

I would not buy an abused flail unless you could actually test it first. A bent main rotor is a big problem.

Very good points and the main rotor is an expensive problem! (I been looking at some flails and been checking parts availability and costs and a rotor is big bucks)
Good luck on your search

 

[IslandTractor]

Agree with above comments. A bent main rotor is essentially impossible to fix properly without expensive dynamic balancing equipment that the manufacturers use in building them. You'd probably have to simply replace the main rotor which would be quite expensive (pretty sure it is the single most expensive part on a flail mower). If it is just the rear roller that is bent, you could probably bang that back into shape or fabricate a new one with steel pipe (maybe salvage the ends and reweld to a new pipe). Dents don't matter in the rear roller but a bend would cause the mower to go up and down giving a wobbly uneven cut.

 

[Blade Breaker]

I found another type of swing flail mower. Berti makes a bunch of options. Looking at something similar to model TA/PS 220

Anyone had any experience with these?

http://www.edneyco.com/assets/files/category_public/Cutters and Mowers/Berti Flail Mowers.pdf

 

[Kodiak45]

Yes it was at 540pto. It's just odd on how it really didn't cut anything. I think the height is set at about 4 inches. It's one hole from the highest, which I believe is 5 inches. Take a look at these pics. The 2ft tall Johnson grass was only pushed over. I'm going to have to get all new bolts and blades. All the bolts and nuts are rusted on and for the most part stripped. It was hard to tell even what size socket to use. I'm probably going to have to grind or torch them all off. I tried for almost 30 minutes to get just one off so I knew what size and length to replace them with and after fighting the fire ants from the grass from being on my back I decided to give up. I need to go ahead and order some blades so maybe I can cut this weekend. One of the bearings had a little resistance, but it wasn't grinding or anything and I can easily turn it by hand, but i'll probably go ahead and replace both the roller and shaft bearings as time allows. I just wanted to make sure the cutting shaft wasn't warped or bent before I put a bunch of money in this thing.
On another note, what is the overload point on flail mowers, meaning I'm used to seeing a shear pin or slip clutch. I assume it's just belt slippage maybe and a burnt up belt. I know the blades will just pivot back if a rock is hit, but I guess there is no break point between the tractor and gearbox.

Am I crazy or these blades don't seem reversible. I got my new blades thinking the cutting edge would be down, but its on the back side of the open faced V. Leonz said the reverse cutting side should be better, but these new blades do not seem reversible at all, only one cutting side has an edge.. help me figure this puzzle out. The flail rotor spins the same at tractor tire...forward motion.. The open faced V side is not doing any cutting..? right?

 

[IslandTractor]

View attachment 437248

Am I crazy or these blades don't seem reversible. I got my new blades thinking the cutting edge would be down, but its on the back side of the open faced V. Leonz said the reverse cutting side should be better, but these new blades do not seem reversible at all, only one cutting side has an edge.. help me figure this puzzle out. The flail rotor spins the same at tractor tire...forward motion.. The open faced V side is not doing any cutting..? right?

I've only seen double edged blades myself. Certainly if blades are single sided then the direction would be critical. You should be able to determine which way the rotor spins by raising the 3PT, turning off the PTO and then dismounting to watch it slowly come to a halt.

 

[smilinjak]

Hi Guys,
I'm looking at a used 84' Motrim flail mower on eBay. It looks good, knives really good, but the upper hitch is slightly bent down. I'm also looking at a ford 918H eight footer, also on eBay, but it looks like it was backed into something. The roller looks slightly bent.
The allure is that these are both around $1200, and I have to keep about 20 acres of pasture down while we are without cows. Any thoughts? I run a ford 7000 as my mowing machine, it runs a woods 84 and doesn't know it's there. I'm looking for a better finish, with mowing about every 3-4 weeks. Can I run one of these at 8 MPH, or fourth gear on my ford?
Thanks

You must have a very large and powerful tractor to run any kind of 84 foot mower at 8 mph. Is there possibly a typographical error or do they have big mowers in Indiana?.
Smilinjak

 

[whirly]

View attachment 437248

Am I crazy or these blades don't seem reversible. I got my new blades thinking the cutting edge would be down, but its on the back side of the open faced V. Leonz said the reverse cutting side should be better, but these new blades do not seem reversible at all, only one cutting side has an edge.. help me figure this puzzle out. The flail rotor spins the same at tractor tire...forward motion.. The open faced V side is not doing any cutting..? right?

This looks like your blades and it does have only one cutting edge.

If in fact the blades are installed backwards then you certainly should be able to turn them around. However, I would check visually like Island suggested to insure your rotor is turning the way you think it is.

 

[Kodiak45]

The rotor does appear to turn in reverse rotation, which does make sense as this would give it the ability to recut clippings. Forward spinning rotor wouldn't cut very efficiently. I thought the blades were mounted backwards, but it does not seem to be the case as the edge of these has formed on the open v side. I hope new blades will make this thing cut, especially after 5-10 hours of welding and metal prep for paint. There is no reason it shouldn't cut well, I'm just surprised the old blades didn't cut at all.

 

[leonz]

The rotor does appear to turn in reverse rotation, which does make sense as this would give it the ability to recut clippings.
Forward spinning rotor wouldn't cut very efficiently. I thought the blades were mounted backwards, but it does not seem to be the case as the edge of these has formed on the open v side. I hope new blades will make this thing cut, especially after 5-10 hours of welding and metal prep for paint. There is no reason it shouldn't cut well, I'm just surprised the old blades didn't cut at all.

=============================================================================


NOW before this discussion crashes into an iceburg in August:

1. you have no real edge left to cut with on these old side slicers.

2. the side slicer rotor as well as the scoop knife rotor rotate clockwise
as you are facing the (non pulley) side of the flail mower,
the tires on your mule are operating in a counter clockwise direction.
the mowers rotation It may seem like its counterclockwise but it is an optical illusion much
like tire spinning at high speeds or while watching wheel spinner rims
at a high speed.

3. apparently the previous owner or owners of this beautiful piece of
mechanical engineering(thank you Mr. Mott) were not interested in flipping
the cutting edge or replacing side slicers.

4. there are you tube videos of front mounted flail mowers doing this.


I wil be back in an hour.

 

[IslandTractor]

I cannot tell from the photo of the mower whether those are single piece one sided "scoop" blades or simply a pair of worn Y shaped blades. I've never seen a one sided Y blade pair but all scoop knives are one sided.

 

[Xfaxman]

Am I crazy or these blades don't seem reversible. I got my new blades thinking the cutting edge would be down, but its on the back side of the open faced V. Leonz said the reverse cutting side should be better, but these new blades do not seem reversible at all, only one cutting side has an edge.. help me figure this puzzle out. The flail rotor spins the same at tractor tire...forward motion.. The open faced V side is not doing any cutting..? right?

The rotor does appear to turn in reverse rotation, which does make sense as this would give it the ability to recut clippings. Forward spinning rotor wouldn't cut very efficiently. I thought the blades were mounted backwards, but it does not seem to be the case as the edge of these has formed on the open v side. I hope new blades will make this thing cut, especially after 5-10 hours of welding and metal prep for paint. There is no reason it shouldn't cut well, I'm just surprised the old blades didn't cut at all.

I think the reason it didn't cut well is because they are on backwards. :thumbdown:

I cannot tell from the photo of the mower whether those are single piece one sided "scoop" blades or simply a pair of worn Y shaped blades. I've never seen a one sided Y blade pair but all scoop knives are one sided.

 

[IslandTractor]

I think the reason it didn't cut well is because they are on backwards. :thumbdown:

You mean someone put something on backwards?? That's the first time in the history of TBN a part was mounted bassackwards (not).

It really depends on which way the rotor is spinning. If it counter rotates compared to tractor wheels then it seems to me the one sided scoops are incorrectly mounted as they would cut moving forward under the rotor. The photo is taken looking towards the rear of the mower so the blades are backwards.

 

[whirly]

My belts are on the left side of the flail (OLD MOTT 72) when looking at the tractor from the rear and the rotor does turn in the same direction as the tractor wheel. However that is a counter clockwise motion from that perspective. To be clear the cutting edge of the blade, on my flail, comes from the top and cuts forward and to the rear at the bottom. This is exactly what your picture shows the blades are positioned for.

In my experience with "Y" blades, even dull blades will beat some of the grass enough to leave some clipping shreds if the grass is long enough and you are going slow enough. So the questions are:

1) How long is the grass you are trying to cut in relation to the height of the blades from the bottom of the roller at their lowest point of attack?

2) How fast are you going?

Scoop blades have a wide face and there is "wind resistance" which could cause the blade to "fly" a bit higher than the setting in #1 above would indicate.

 

[leonz]

I think the reason it didn't cut well is because they are on backwards. :thumbdown:

Getting back to this 10 hours later; they are side slicers that are so far gone.........

If you look closely the row above has several "single side slicer knives laying against the rotor.

A scoop knife would not split like that as the knife blank is thick enough that it cannot fold over.

Look closely at the image(s)
These knife hangers permit the side slicers with the slotted mounting holes much more movement as compared
the restrained side slicer knife hangers that have the single punched hole or slotted hole.
As I have described previouly the slotted knife and the wide D knife hanger and the knife hangers on my mathews alllow the knife to become an airfoil allowing a level cutting edge when the rotor spins at the proper speed of rotation-2,200RPM+-

 

[leonz]

I think the reason it didn't cut well is because they are on backwards. :thumbdown:

====================================================================
Getting back to this 10 hours later; they are side slicers that are so far gone.........

If you look closely the row above has several "single sie slicer knives laying against the rotor.

A scoop knife would not split like that as the knife blank is thick enough that it cannot fold over.

Look closely at the image(s)
These knife hangers permit the side slicers with the slotted mounting holes much more movement as compared
the restrained side slicer knife hangers that have the single punched hole or slotted hole.
As I have described previouly the slotted knife and the wide D knife hanger and the knife hangers on my mathews alllow the knife to become an airfoil allowing a level cutting edge when the rotor spins at the proper speed of rotation-2,200RPM+-

 

[Xfaxman]

What type is this, that whirly posted?

That is what I see the back of in the dimly lit picture.

 

[IslandTractor]

I think Xfaxman is right. Those are scoops. Still unclear if they are mounted backwards though. Has the OP confirmed rotation?

 

[leonz]

OK, now that I can see the mess with a little more clarity-

Scoop knives-being the proper name always face forward to
cut the material. These scoop knives are apparently mounted BACKWARDS
and they should not be backwards EVER.

It explains a lot and the poor cut, new scoop knives are needed.
Saying that I am unsure if the rotor knife mounts as they exist in
the current spacing can use the knife pairs. Saying that the JD 25A
did have at one time multiple mounting stations to allow both knife
types to be mounted using more knife hanger stations for the side slicers.

It was hard for me to tell due to the condition of the knives and rust under
the flail mower. I beg forgiveness from the members of the flail mower nation
for my mistake.


The scoop knife operates just like the side slicer knife pairs, the material is cut and
then lifted up and over the flail mower rotor back to the ground.

The scoop knife is dual purpose knife for brush and cutting grass; these scoop knives are used for flail choppers that cut haylage and the haylage is lifted into the cross auger of the flail chopper that feeds the material to an impeller fan that blows the haylage into a wagon.

The flail choppers offered by Hiniker do not use a cross auger where in the haylage is blown directly up and out of the flail chopper through the duct used to direct the flow of material.
If I had a newer computer I would post a picture of it.