How do I get clean cut with Brush Hog?

[granteck]

I have a Kubota 9200 and was running an old Dorsey 5" Brush hog (probably made back in 1950's) and was getting a nice clean cut, but last year the gear box seal went. Looking at repairing it but the stump jumper is welded to the shaft, no nut. Going to take sometime to get it apart and to find the parts. In the meantime I picked up a 54" Woods Heritage and no matter how I try to set it up I get a poor cut. I have the front slightly lower than the rear, but it tends to leave a row that looks like I ran it over and did not cut it. It takes multiple pases to get the field cut consistently. Running PTO at 540 and engine at high throttle and tranny in low gear so I am not going fast. At first I thought that maybe the blades were on backwards or the rotation was backwards. Blades have a good edge on them.

I am not looking for a mowed field like i would get with a regular mower. I am just looking to get a consistent cut and not leave the stragglers behind. Any ideas on why I am getting such a poor cut would be appreciated.

 

[Verticaltrx]

My guess is that with the Woods Heritage series being an economy cutter it has a low blade tip speed. The cutters with a higher blade tip speed make a cleaner cut and pick up more of the grass the wheels run over. One trick to try is mow the first round clockwise, then the next round counterclockwise, back and forth This will help to pick up that strip that the outside wheels mash down.

 

[Marveltone]

Blade speed is 14,657 fpm @ 540 rpm. While there are certainly faster cutters out there, it seems to be in line with many others in the 60" range. Certainly not the slowest. Of course, when cutting grass, blade speed is king. My HC54 does what I need it to do as long as I keep the speed low in the tall grass. If I'm just tending to the trails, which never get too high, I can cruise along at a pretty good clip.

Verticaltrx has a good idea to try picking up the mashed, driven over grass. I've never tried it, as I've been satisfied with the results I've had, but the OP may want to give it a try.

Joe

 

[Ed of all trades]

I don't know about a woods mower but I have seen some that the cut was improved by closing off the hole in the deck os as to get better a better suck on the grass. lay something over the hole and see if it helps. Its a cheep try and if it helps you can do it right

 

[Mark Page]

Is your deck level? Get on a smooth level surface and measure from the bottom of the deck skirt to the ground on both sides and use you're leveling box to get them the same. When I used to mow with a rotary mower I could get a pretty nice job this way. Not finish mower quality, but close. Are you saying that high idle gets you 540 RPM?

 

[granteck]

Thanks to everyone who replied. I have the front about 1" lower than the rear which is what Woods and all the writeups recommend. When I said 540 that was the PTO setting. I run the rpms at a high setting. I didn't look at the tach. The strip that it leaves is not in line with the wheels. It appears to more right down the center. do other brush hogs do a better job. I can't switch to a real mower until I get the fields leveled out. Right now I keep flipping up rocks and logs so it is too rough.

Any other feedback would be appreciated.

 

[Mark Page]

Just for grins, try raising the whole deck up or down and see if it makes a difference. I've got a feeling you may be cutting too high. You may have to lower the tail wheel. Having the front of the deck 3"s lower than the rear won't hurt either.
I still don't understand your pto speed. Are you saying you san run the PTO speed and the tractor speed independantly? No matter what, you want that pto speed at 540 or more, for me that works out to about 2,000 RPM. Adjust the tractor speed with the gears. You may want to go down a gear. Is your pto live or independant?
If it's set up right there's no reason you shouldn't get a nice cut.

 

[jkis]

you might want to check the ratio on the bushog just to make sure its right
cheers stuart

 

[tmeadows]

Is the woods a brush hog or a finishing mower? sounds like the woods mower has 2 blades and is leaving a streak where the two blades over lap. Does the woods have belts on it?

 

[OldGinTractors]

Did your old cutter have a stump jump or just a blade bar? Normally a cutter with a large round blade carrier will not cut as clean as one with just a bar. Also lots of old cutters used shorter blades vs. newer cutters 2ft. long blades.

 

[MESSMAKER]

If you have the horsepower to spare, try lowering the rear of you cutter. This means raising your tail wheel. You will will use more fuel, but you get more cutting action. Sharp blades can help when cutting grass. I can't see any help in tough stuff though.

 

[boggen]

rear end of old BH is it round? or square shape? or rhombus shaped?

same question for new BH. the rear end an how it is shaped. can make a difference in the "wind current" that is created by the blades to pull the weeds / grass back up. a rounder back to a BH. will allow for better window currents, a box shape back end of a BH is not the best for creating wind currents that can help pull weeds and grass up.

also do you have a rear end side? or open back? or perhaps open back with some chains hanging down? rear end with a solid piece of sheet metal. will allow better wind currents to help pull weeds / grass back up. open back. just sends stuff straight out, open backs with chains, are more geared in trying to keep stuff from flying out and hitting something.

physically setting the tail wheel lower, and 3pt hitch lower. so entire BH sets lower. will allow better wind currents under the BH, to help pull up weeds and grass to be cut.

ditto messmaker reply. getting so front and back of BH to set level. can help create better wind currents to help pull weeds / grass back up.

===================
on a side note. rotatory cutters aka (bush hogs) are there to cut down tall weeds. they normally do not leave a pretty look afterwards like a regular finishing mower. due to the "clumps of grass/weeds" (aka windrow) they leave behind them.

taller the weeds, greater chance a weed is still caught up under a rear wheel of tractor. and really never gets a chance to lean back up into the blades. resulting in stragglers.

 

[vtsnowedin]

I have my tires set wide so they don't mash down the grass just before you mow it. The right side wheels are out in the next pass but the grass has whatever time it takes me to get around the piece to stand back up. The left side wheels (mowing clockwise) are out in the already cut grass. I'm still getting used to mine and I haven't tried any different tail wheel positions but they way the dealer set it seems OK. What I may do soon is switch the back braces to chains as the linkage there doesn't have enough range of motion to follow the rougher sections of ground I'm mowing. When ever the front of the tractor starts up a steeper incline I have to raise the level control or the cutter will bottom out.

 

[nuffer460]

This spring, I had allot of rain in April. I had a bearing issue with my 6' finish mower. I looked at my father-in-laws old IH 411 Rotory Mower. It's old, bent and very heavy. It is a long bar type with about 12" blades. I hauled it to the barn. Checked it out. Greased the pto shaft. Sharpened the 1/2" thick blades. Mowed my front lawn with it. I mowed the front on a diagonal. Changed directions cut it again. I do the same with the finish mower. This mower is probably all of 40 years old, and it looks it. It produced a better cut then my finish mower. I could not believe it.

 

[cisco]

Not sure where your Woods fits into their prior lines, but I have a current line 72" and it will not cut anywhere near what a finish mower, or for that matter the zero turn mower I usually use, can do on grass. Keeping the PTO at or above the usual 540, and having sharp blades (I take mine off 1-2X per year to grind or replace them), should give a decent result. And, yes, I agree that most sites recommend keeping the front of the brush cutter a bit lower than the rear.

 

[granteck]

Tomorrow I will try duct taping something over the hole and see if that makes a difference.

 

[granteck]

No I am not running the deck level as that is not what they say to do. Everyone reecommends setting the front lower than the rear.

540 is the PTO setting. I run at the a high throttle so it doesn't stall out and I have the power for big clumps or rocks. Probably confused some by mixing the 2.

 

[granteck]

Just for grins, try raising the whole deck up or down and see if it makes a difference. I've got a feeling you may be cutting too high. You may have to lower the tail wheel. Having the front of the deck 3"s lower than the rear won't hurt either.
I still don't understand your pto speed. Are you saying you san run the PTO speed and the tractor speed independantly? No matter what, you want that pto speed at 540 or more, for me that works out to about 2,000 RPM. Adjust the tractor speed with the gears. You may want to go down a gear. Is your pto live or independant?
If it's set up right there's no reason you shouldn't get a nice cut.[/QUOTE]

I raised the rear today one bolt hole and will try it tomorrow. I now have a bigger difference between the front and the back. Looks high to me. I already lowered the rear a lot from what came from the dealer. There was only 1 hole lower to go in the rearbefroe I raised it today. I would love to hear from someone running a 54" Heritiagge as to their settings.

As far the the PTO I am runing at 540. My mention of the throttle was only so I do not stall out. I have stalled with lower throttle settings.

Sorry for the slow replies but I work out of state so I only get to run the tractor on weekends.

 

[granteck]

Did your old cutter have a stump jump or just a blade bar? Normally a cutter with a large round blade carrier will not cut as clean as one with just a bar. Also lots of old cutters used shorter blades vs. newer cutters 2ft. long blades.

The old brush hog had a big round fly wheel type stump jumper. The new brush hog has a plate type.

It was open in the front and rear. See attached pictures.

 

[joshuabardwell]

It's hard to judge anything from those two picture you're posting, because the tail wheel is turned around backwards. If your cutter is anything like mine, the rear drops several inches when the wheel turns around front-wards. If you're going to adjust the height, flip the wheel around front-wards before you do it. In the pics, it looks like the front of the mower is riding a few inches lower than the rear, but I bet you once the tail-wheel flips around, the back is going to be level with the front, or maybe a smidge lower. I'm not sure that's what you're going for.