Rear Blade Scrape blade width for my tractor?

rowlettr · Sep 7, 2010

I have a Kubota B2920 (28 hp). The rear tires span 4 ft outside to outside. I have a dirt road that is sloped the wrong way. I have tried to grade it with my box blade, but since the box blade follows the slope of the tractor, I cannot change the slope of the road.
I want to move dirt off of one side and create a ditch on the new, lower side. I think a scrape blade that angles and tilts is what I need. The road is fairly rocky, so I am concerned about damaging the blade, or having it bounce over the rocks instead of moving dirt. Would that call for a more "heavy duty" blade?
I also need it to reach beyond my tires so that I won't be driving in the ditch while I scrape.. Is 1 ft on each side enough? That would call for a 6 ft blade, or should I consider a 7 or 8 ft blade?
Thoughts?

oldballs · Sep 7, 2010

I just went through a similiar discussion with myself on this subject. My conclusion using a smaller tractor than yours viz., BX2660 is that a 5 ft blade that weighs 269 lbs is plenty of blade for this tractor especially on slopes or ditching. The B series Kubota could handle a 6 ft blade easily in a similiar situation. As to a 7 ft or larger, you'd better get somebody else's opinion.

KU Gator · Sep 7, 2010

I bought a 5' Landpride for my B2920. I tried a 6' & a 5' on mine before deciding and went with the 5' in the end because I wanted to be able to use it to create a trench which required tilting it and angling to the maximum. When I did that I could not raise it high enough with the 3 pt hitch to get the 6' one to the greatest tilt position. I am still a bit on the fence as to if that in the end was the best decision. In the winter I use it for snow and the 5' just does cover my tracks when it is angled to the max. I bought the Landpride because there was a dealer going out of business and I got a pretty good price on it. Had I have went to the dealer I got the tractor from, I would have probably gotten a Bush Hog as that is what he tends to stock. I think they are pretty similar in quality. My drive is rock, and I tend to find the box blade the more usefull tool and tilt it using the adjustment on the arms of the 3 pt hitch. I use the rear blade primarily for the snow removal.

JDGreenGrass · Sep 7, 2010

Couldn't you lower the scarifiers to loosen the material and then move the gravel to where you want it.??

I would think a box blade would be ideal for what you describe. No.??

Do you have pictures of the area you are trying re-work.??

brandoro · Sep 7, 2010

I use the Landpride grader/scraper on my lane, it does a nice job. When I was creating some crown on the lane I used the adjustment on the right lift linkage to get some tilt. Now that I have some crown I leave the adjustment flat and just maintain what's there.
My B3030 pulls the G/S easily, only occasionally needing the front wheel assist. The hydraulic top link is very handy with the G/S.

rowlettr · Sep 7, 2010

KU Gator said:
I bought a 5' Landpride for my B2920. I tried a 6' & a 5' on mine before deciding and went with the 5' in the end because I wanted to be able to use it to create a trench which required tilting it and angling to the maximum. When I did that I could not raise it high enough with the 3 pt hitch to get the 6' one to the greatest tilt position. I am still a bit on the fence as to if that in the end was the best decision. In the winter I use it for snow and the 5' just does cover my tracks when it is angled to the max. I bought the Landpride because there was a dealer going out of business and I got a pretty good price on it. Had I have went to the dealer I got the tractor from, I would have probably gotten a Bush Hog as that is what he tends to stock. I think they are pretty similar in quality. My drive is rock, and I tend to find the box blade the more usefull tool and tilt it using the adjustment on the arms of the 3 pt hitch. I use the rear blade primarily for the snow removal.

I went to the Kubota dealer today and he mentioned that if I had a 7ft blade, I would not be able to angle it enough. This confirms what you said. I have found 5ft blades that tilt, angle, and offset. That means the whole blade assembly will shift left a foot or so to give me the side reach I need, plus tilt and rotate. I may have the same tilt/ground clearance problem as with the 7 ft blade though because the 3 pt lift will only raise it so much. The brands I found are Bush Hog and Tennessee River.

Baby Grand · Sep 8, 2010

Do you have any adjustment for the top link forward mount? Some have a vertical set of holes on the transmission mount that let you get a little more lift from your 3PT hitch.

For ditching I get very good results with a middle buster - you'd need to have enough shoulder to straddle the ditch.

-Jim

KU Gator · Sep 8, 2010

I think 7' would be pretty big for the weight and power of that tractor. I know some mention the even with snow, the rear blade wanting to pull the tractor sideways. Also, I know the odds that I would forget about it back there and catch that on something such as the garage door would be about 100%, but maybe not for you. Your dealer might have been talking about the ability of the blade to spin 360 deg without hitting the tire.

When you put the blade at the max angle and tilt, it is standing almost verticle. I don't remember if I tried shortening up the upper link to the minimum or not, but the 6' did not quite make it. I believe I saw that you had a backhoe, so that ability may not be that important to you or as Baby Grand indicated you could dig a trench with a middle buster.

In the end, I am ok with the 5' one, but I imagine if there was a poll taken, 6' would win for that size tractor.

I don't know anything about Tennessee River brand. I think the Bush Hog is pretty well built. Woods is usually pretty well recommended. The Landpride I got is their line for 17 - 40 hp and seems plenty stout for that size tractor.

rowlettr · Sep 8, 2010

Baby Grand said:
Do you have any adjustment for the top link forward mount? Some have a vertical set of holes on the transmission mount that let you get a little more lift from your 3PT hitch.

For ditching I get very good results with a middle buster - you'd need to have enough shoulder to straddle the ditch.

-Jim

I have an adjustment (turn buckle type) for the top link of the 3 pt attachment arms, and one for the right link. I guess the tilt of the attachment depends on whether I adjust the right link up or down. I have 2 holes for the top link at the tractor frame. I don't know why there are 2 or which one would give me more lift. It seems to me that the side arms determine the amount of lift. The top holes look like they would affect whether the attachment is plumb. Am I missing something?

KU Gator · Sep 8, 2010

I have never changed where my top link attaches to the tractor from the top hole. I would think the top hole would give the greater lift, but haven't really thought about it. Some of the implements I have also have an upper or lower hole.

Yes the turnbuckle on the right side is to adjust the angle of the blade. Of course some rear blades, like the one I bought, also tilt, but not all of them do.

My rock drive was having problems with puddles when there was a rain. So I use the box blade and angled it so the right side was low. Then ran down the drive on the right side and back up on the other side. I did this mostly with the scarficers down to break it up. It did a pretty good job of crowning it and eliminated the puddle issues. By adjusting the top link, it also makes a difference as to how much material you move.

clemsonfor · Sep 9, 2010

read the first post, but not much else so it may have been mentioned.

While the Box blade folows the angle of the tractor, you can adjust your arms to angle it moving the left or right side higher on the BB. If your talking about angling the blade so part of the blade is farther foward then your out of luck with a bb!

Baby Grand · Sep 9, 2010

KU Gator said:
I have never changed where my top link attaches to the tractor from the top hole. I would think the top hole would give the greater lift, but haven't really thought about it. Some of the implements I have also have an upper or lower hole.

...

I found that the lower hole allows me to lift my potato plow enough that I don't scalp the field grass on the trip from the shed to the potato hills. It also seems to run the plow a bit deeper set in the lower hole. I think it amplifies the motion of the rockshaft thru the 4 bar linkage.

-Jim

/pine · Sep 9, 2010

...I have 2 holes for the top link at the tractor frame. I don't know why there are 2 or which one would give me more lift...

My manual says the top hole (1) is "standard"...

it states: "(2) is used only when there is some obstacle that prevents you from using the standard"

I moved my top link cylinder to the lower hole to give more clearance for the check valve and hoses when the lift is raised all the way up...

Gordon Gould · Sep 9, 2010

A box blade is a wonderful tool but if you need to move material across the road a rear blade is the only way to go (IMO). One pass with an angled rear blade will move more material across the road than 10 passes with a box blade.
You have been given alot of good ideas on blade width but one thing that hasn't been mentioned is that if the blade is to wide you cant turn it around backwards without hitting your tires. It is very handy using a rear blade backwards for smoothing. Of course you could do that in reverse gear. My tire width is 5' and my blade 6', offsettable by a foot. This seems about right for road work.

Johndeere3720 · Sep 9, 2010

I also have a boxblade and rear blade. here's a video of my rear blade working the driveway. I gotta say that gauge wheels make a word of a difference for me. Using my blade on the driveway - Tractor Videos - Kubota, John Deere, New Holland and More For tilt, i just ajust the right lift arm length and set the top link to desired length/dig. With the gauge wheels, i can use them to determine if i wnat to dig a lot or just scrape snow off the driveway. Very simple to use and it is very affective, especially with 6 40 pound weights on it. My gauge wheels can pivot for turns or lock in place for use in reverse or with the weights. they bolt to the blade with only 2 bolts so they are easy to remove if needed.

Gordon Gould · Sep 10, 2010

I set the tilt on my blade differently than most I have seen here. And it seems a lot easier to me. If you need tilt on the blade, that means you want to move material from one part of the road to another. Usually from the edge to the center to build a crown. I put the tractor on a level place raise the blade a inch or so off the ground in the straight position (90 degrees to centerline) and adjust the right liftarm height so the blade is perfectly parallel to the flat surface ( level ). Then I rotate the blade to the angle I intend to use for grading. I then adjust the top link ( usually shorten, which will pick up the back and lower the front of the blade) to set the angle for the new road contour. By doing this no matter which way the blade is angled, left or right, you will develope the same contour cutting angle. You can run up and down both sides of the road in either direction with out making any adjustments other than swingimng the blade. Then if you want to go down the middle of the road to flatten the crown a little, just put the blade straight and it is level.

brucewj · Sep 11, 2010

Gordon that is really good information. I never thought about that.

Thanks for posting this.

slaveToHorses · Sep 11, 2010

KU Gator said:
I have never changed where my top link attaches to the tractor from the top hole. I would think the top hole would give the greater lift, but haven't really thought about it. Some of the implements I have also have an upper or lower hole.

It is actually the other way around. At least on all the machines I have worked with.
If you look at a 3pt hitch from the side, you can see that the pivot point for the implement (blade) is where the pins (on the blade) attach to the lower arms of the 3pt. The maximum distance from the ground to the pivot point is solely determined by the rotational angle of the rockshaft and the length of the lift links. They determine the angle upwards of the lower arms.This assumes that lift arms and lower arms have a fixed length, which is the usual case.

The top link determines the angle of the implement, at the pivot point. As the lower arms raise, they work against the top link and force the attachment to pivot back (thus lowering the back of the blade). The reverse happens when the arms lower the attachment. So, if you lower the attachment point of the top link at the tractor, you will change the way the implement rotates about the pivot point. The lower the attachment point for the top link at the tractor, the less the implement rotates back. The result is the more clearance between the ground and the back blade, at the back of the blade.

The relationship between the top link attachment point and it's length is as follows. The attachment point changes the relation between the rotational angle and the lower arm lift angle. The length of the top link changes the minimum and maximum amount of rotation.

So, in general, use the length of the top link to determine the angle of the blade when down on the ground. Use the top link attachment point to alter the angle of the blade when it is fully raised.

Now if everything is perfectly square, in other words if the vertical line drawn up from the point where the lower arms attach to the tractor intersects the point where the top link attaches to the tractor and the same is true for the attachment points on the implement and the length of the lower arms and the top link is the same and the vertical distance between attachment points is the same at the tractor as it is on the implement, then the implement will maintain the same angle as the lower arms and no rotation will occur. That is the neutral position.

Oldmax · Sep 13, 2010

I have a 27HP FWD tractor and use a 6' blade . It will suprize you how much those little tractors will pull. If you go over 6' you have to take blade off to turn around.