ROTARY CUTTER STRUTS

[flINTLOCK]

My Woods Brushbull 72" cutter has 2 metal "straps" running from the toplink attachment area spreading out to the rear of the deck. They bend substantially during operation. I'm wondering if I'm somehow setting the hydraulic toplink too long to accommodate the ups and downs of my property. You can readily see the stress in the metal where they bend. Paint cracks off at those spots. Any suggestions??

 

[Farmwithjunk]

The same "struts" do the same thing on my BB840. 3rd season and not problems SO FAR. They looked like a poor design from day one.

 

[Ford850]

Does your woods have a flexible toplink connector? Most will have a hinged connection point so the tailwheel end of the cutter can flex upwards if needed. If yours has a hinged setup, you might have your toplink set too long. Check the instructions to be sure it was put together correctly too. Sometimes they are assembled backwards. If assembled correctly, and the toplink is adjusted correctly, your rear of the cutter should be able to float up or down at least 6" from level to folllow the contours of the gound without binding.

 

[Soundguy]

I agree with Ford850.. those straps are bending because they are being put under compressional stresses as the mower tries to rotate around the lower lift pns.. .. this maens the toplink is too long.. or the flex connection is not installed or working right. If your TNT has a 'float' onthe toplink cyl... I'd use that setting.

Soundguy

 

[JerryG]

I don't know what kind of remote valve you have but if it has a float position use it. That will take care of the problem.

 

[Farmwithjunk]

. .. this maens the toplink is too long.. or the flex connection is not installed or working right.

Soundguy

Not neccesarily so.... There is a flexable link at the A-frame and these struts attach to it. There is enough "float" in that flex point to allow 18" to 24" of movement up and down at the tailwheel. (on my 84" BB840) In some cases (extremely rough ground) you'll get more travel than they allow. NORMALLY, with a rigid "strut" it would force the mower to raise, both front and rear. With these rather flimsy flatbar struts, they simply bend and flex to absorb the compression. But it DOESN'T take full movement of the flexable link to make the bars bend. The design is so that even with flex remaining unused (in the A-frame flex point) the struts still bend as they offer less resistance than the flexable movement built in to accomodate the problem. I use a hydraulic top link with my BB840. I've tried shorter and longer positioning. Neither yields satisfactory results.

They're working as designed, just that the design isn't the best unless you're mowing flat ground. This design (and mower) is a perfect candidate for using a section of link CHAIN in place of these flimsy bars. I'm thinking the built in flex linkage would move even easier that a normal "floating" of a hydraulic cylinder. The flimsy bars may (and in my estimation WOULD) still flex even with the hydraulic top link in float. (My hyd. top link has pilot operated check valve.....it doesn't float)

They're just too flimsy.

My personal evaluation of the problem is, Woods uses the same basic set-up with light, medium and heavy duty mounted mowers, 7' and smaller. The bars are (barely) adaquate for light duty (BBxx) but render themselves too light for medium (BBxxx) and heavy (BBxxxx) duty models.

I've never been real pleased with the BB840 for a number of reasons, this being just one of them.

 

[Soundguy]

Great minds think alike..

Soundguy

 

[flINTLOCK]

That's a good point. Replacing them with chains would be an idea when they show more wear/weakening.

 

[Soundguy]

I don't think I'd like that design very much.. or at least i wouldn't prefer it anyway..

Soundguy

Not neccesarily so.... There is a flexable link at the A-frame and these struts attach to it. There is enough "float" in that flex point to allow 18" to 24" of movement up and down at the tailwheel. (on my 84" BB840) In some cases (extremely rough ground) you'll get more travel than they allow. NORMALLY, with a rigid "strut" it would force the mower to raise, both front and rear. With these rather flimsy flatbar struts, they simply bend and flex to absorb the compression. But it DOESN'T take full movement of the flexable link to make the bars bend. The design is so that even with flex remaining unused (in the A-frame flex point) the struts still bend as they offer less resistance than the flexable movement built in to accomodate the problem.

 

[john_bud]

My Woods Brushbull 72" cutter has 2 metal "straps" running from the toplink attachment area spreading out to the rear of the deck. They bend substantially during operation. I'm wondering if I'm somehow setting the hydraulic toplink too long to accommodate the ups and downs of my property. You can readily see the stress in the metal where they bend. Paint cracks off at those spots. Any suggestions??

Flintlock,

Can you post a picture of your typical setup? I have a BB600 and haven't noticed any bending. Just wondered how you were set up in comparison.


Can you also check the looseness of the top flex link and strap bolts. They should be all free to rotate. If they were torqued down hard, I could imaging them being forced to bend when they should rotate.

jb

 

[N80]

This is no help to the OP but I particularly like the flexible link on my JD LX-6 mower (which is otherwise a run of the mill light duty mower). This design allows for a lot of flex and you can control how much by the position of the top link relative to the position of the mower at desired mowing height.

 

[Farmwithjunk]

I don't think I'd like that design very much.. or at least i wouldn't prefer it anyway..

Soundguy

I KNOW I don't like it much at all. Woods makes a decent mower but they've targeted a different market in recent years. They try to make their mowers look good, with clean lines and a streamlined shape. I'd much rather have a mower that's tougher than a $2 steak and a little crude looking. Prior to buying this mower, I bought an MD172, their previous generation model (in a 72" width) It is a MUCH better designed and built product. In the name of saving $290 over what I would have spent on a 7' Bush Hog brand, I got the Woods. So much for saving a few bucks.

This same mower has a tendency to blow chaff and clipping out from under the front end (and therefor, all over the operator) It also doesn't "lift" grass and weeds mashed down by the tractors rear wheels nearly as well as my Bush Hog mower. Add all that to the fact that 7' single spindle mowers tend to scalp far worse than a 6' single or 8' double spindle, and I'm not at all happy with this mower. It goes away this winter. It'll be replaced with a 10' or 12' Bush Hog brand flex wing cutter before next cutting season.

 

[Soundguy]

I've been looking at a bunch of mowers that mu neighbors use lately.. and trying to figure out what.. if any, difference the mower sidewall has to do with the blown out 'chaff' you mention. My 5' KK blows a bit and has fairly short side walls.. perhaps 5".. I have a guard installed on front and that pretty much eliminates 99% of anything out the front. My 10' non flex mower also has short sidewalls, compaired to blade height.. IE.. I can mow down to about 2" with it.. VS my JD 1517 flexwing that has fairly long side walls that prevent me from getting closer than 3.5 to 4" or so.

I much prefer the flex mower on any bit of low area vs the wide fixed deck 10' unit. I saw a guy with a fixed 12'er.. ( hadn't seen one before ".. and thought.. 'man. that thing must scalp something awfull unless mowing a ballfield or something.. "..

Gotta agree on large single spindle mowers.. i think I'd prefer dual spindles for sure.. probably less HP requirement to boot..

Soundguy

I KNOW I don't like it much at all. Woods makes a decent mower but they've targeted a different market in recent years. They try to make their mowers look good, with clean lines and a streamlined shape. I'd much rather have a mower that's tougher than a $2 steak and a little crude looking. Prior to buying this mower, I bought an MD172, their previous generation model (in a 72" width) It is a MUCH better designed and built product. In the name of saving $290 over what I would have spent on a 7' Bush Hog brand, I got the Woods. So much for saving a few bucks.

This same mower has a tendency to blow chaff and clipping out from under the front end (and therefor, all over the operator) It also doesn't "lift" grass and weeds mashed down by the tractors rear wheels nearly as well as my Bush Hog mower. Add all that to the fact that 7' single spindle mowers tend to scalp far worse than a 6' single or 8' double spindle, and I'm not at all happy with this mower. It goes away this winter. It'll be replaced with a 10' or 12' Bush Hog brand flex wing cutter before next cutting season.

 

[Ford850]

I've been looking at a bunch of mowers that mu neighbors use lately.. and trying to figure out what.. if any, difference the mower sidewall has to do with the blown out 'chaff' you mention. My 5' KK blows a bit and has fairly short side walls.. perhaps 5".. I have a guard installed on front and that pretty much eliminates 99% of anything out the front. My 10' non flex mower also has short sidewalls, compaired to blade height.. IE.. I can mow down to about 2" with it.. VS my JD 1517 flexwing that has fairly long side walls that prevent me from getting closer than 3.5 to 4" or so.

I much prefer the flex mower on any bit of low area vs the wide fixed deck 10' unit. I saw a guy with a fixed 12'er.. ( hadn't seen one before ".. and thought.. 'man. that thing must scalp something awfull unless mowing a ballfield or something.. "..

Gotta agree on large single spindle mowers.. i think I'd prefer dual spindles for sure.. probably less HP requirement to boot..

Soundguy

I have a 72" KK that has the high sidewalls. I do not like the fact that I cannot mow lower than 4" (actually looks like 5" or so since I don't drag the side rails) but it seems to do a good job. The frame and supports are heavy duty, the cut itself seems average, and it hogs down the brush when needed. I even use it to chip black locust sapplings I cut out of fence lines and drag into the field. I've hit some filed stones larger than volleyballs and split them with the blades. Of course if I had a lighter weight model that would allow for a closer cut, I would be complaining about how I tore it up chipping some sapplings.

 

[Dargo]

I called and spoke with an engineer a couple of years ago when I went to the extreme beefing up my 7' rotary cutter. I have a 100 hp gearbox on the cutter but the sides were getting killed when I mowed some of the rough areas on my property. I'd make a required sharp turn and the long deck would swing into a rock or a tree and the blades would start hitting it. Anyway, I built a full cage around the existing deck with 2X2 square tubing with 3/8" sidewall. I attached the tubing using 2X3 angle that is 3/8" thick. By the time I got finished, my 7' cutter ended up weighing over 1500 pounds.

One thing I didn't touch was the two weak pieces of flatbar that go from the top of the 3pt hitch to the rear of the mower. The engineer told me that they are basically only there to allow the 3pt hitch to pick up the entire mower; not to lend any support. He even advised me to take them off and replace them with chain if I have a lot of areas where I go down a steep hill and then right back up another hill. He told me that if I braced those bars so they wouldn't bend I'd take a chance of breaking the top link to my 3pt hitch or worse. Basically, those thin bars are designed to give and flex to prevent damage. If they get too ugly, just take them off and replace them with lengths of chain.

 

[Farmwithjunk]

I've been looking at a bunch of mowers that mu neighbors use lately.. and trying to figure out what.. if any, difference the mower sidewall has to do with the blown out 'chaff' you mention. My 5' KK blows a bit and has fairly short side walls.. perhaps 5".. I have a guard installed on front and that pretty much eliminates 99% of anything out the front. My 10' non flex mower also has short sidewalls, compaired to blade height.. IE.. I can mow down to about 2" with it.. VS my JD 1517 flexwing that has fairly long side walls that prevent me from getting closer than 3.5 to 4" or so.

I much prefer the flex mower on any bit of low area vs the wide fixed deck 10' unit. I saw a guy with a fixed 12'er.. ( hadn't seen one before ".. and thought.. 'man. that thing must scalp something awfull unless mowing a ballfield or something.. "..

Gotta agree on large single spindle mowers.. i think I'd prefer dual spindles for sure.. probably less HP requirement to boot..

Soundguy

When we were shopping for the 15' batwing, I got to talk with a Bush Hog sales rep/"field engineer". I mentioned the chaff out from under the front issue. What he told me made sense. I don't know if he was blowing smoke or not, but it made sense. And since I'm not seeing this problem with either of the Bush Hog mowers I own, I'm assuming he knows of what he speaks. He said the problem was caused by the shape of the BACK end of the mower. A mower deck has a wind tunnel effect. If that "wind" isn't channeled out from under the rear of the mower, it'll take the next logical path of least resistance.... the FRONT. The higher sidewall, when used with a low slung blade carrier is supposed to create more vaccuum, helping to lift grass/weeds, and more air movement. That air movement is supposed to be channeled out the back end to clear clippings that would otherwise bog the mower(tractor) if they tended to stay under the deck longer than neccisary. My Bush Hog 286 has a relatively deep deck, with blades set low enough to cut 2" to 2-1/2" with ease. It has more "lift" than any mower I've used. (In case you can't tell, I'm VERY pleased with Bush Hog's offerings) The more I'm learning about high end mowers, the more I see why Bush Hog and Alamo Group (Alamo/Rhino/Shulte) mowers get such great ratings for commercial and extreme duty applications. They build a darn nice product that WORKS well in extreme conditions.

 

[Farmwithjunk]

I called and spoke with an engineer a couple of years ago when I went to the extreme beefing up my 7' rotary cutter. I have a 100 hp gearbox on the cutter but the sides were getting killed when I mowed some of the rough areas on my property. I'd make a required sharp turn and the long deck would swing into a rock or a tree and the blades would start hitting it. Anyway, I built a full cage around the existing deck with 2X2 square tubing with 3/8" sidewall. I attached the tubing using 2X3 angle that is 3/8" thick. By the time I got finished, my 7' cutter ended up weighing over 1500 pounds.

One thing I didn't touch was the two weak pieces of flatbar that go from the top of the 3pt hitch to the rear of the mower. The engineer told me that they are basically only there to allow the 3pt hitch to pick up the entire mower; not to lend any support. He even advised me to take them off and replace them with chain if I have a lot of areas where I go down a steep hill and then right back up another hill. He told me that if I braced those bars so they wouldn't bend I'd take a chance of breaking the top link to my 3pt hitch or worse. Basically, those thin bars are designed to give and flex to prevent damage. If they get too ugly, just take them off and replace them with lengths of chain.

I'm inclined to agree. I mentioned in an earlier post that my BB840 would be "a perfect candidate" for replacing those flimsy bars with chains. I agree with the concept that they shouldn't be rigid. I DISAGREE with the concept that a flexable "link" should be made out of light gauge bar stock.

 

[flINTLOCK]

Sounds like chains in my future. Thanks guys.

 

[Soundguy]

90% of the big ( 20' ) finish mowers you see in this area are shulte... nice looking things..

Soundguy

I see why Bush Hog and Alamo Group (Alamo/Rhino/Shulte) mowers get such great ratings for commercial and extreme duty applications. They build a darn nice product that WORKS well in extreme conditions.

 

[Farmwithjunk]

90% of the big ( 20' ) finish mowers you see in this area are shulte... nice looking things..

Soundguy

Nice looking price tags too.....So long as you're SELLING and not buying