Grader Attachment

[mtgstuber]

Has anybody worked with a skid-steer grader attachment? I don't mean a box-blade. I mean something like a mini might patrol or Bobcat's grader attachment: http://www.bobcat.com/attachments/grader

 

[Tazza]

I have never used one. All the weight on a skidsteer is in the rear, you don't have that much down pressure to really do the cutting. It may do just fine, but you notice on a grader, the blade is more or less over the engine to give good pressure to the blade.

 

[TriHonu]

I have never used one. All the weight on a skidsteer is in the rear, you don't have that much down pressure to really do the cutting. It may do just fine, but you notice on a grader, the blade is more or less over the engine to give good pressure to the blade.

I have one of the early models that was made by Palm for Bobcat. However I don't have a lot of hours operating it.
When operating it, you lower the boom and roll the Bobtach enough to lift the front tires a couple inches off the ground. This not only transfers weight to the cutting edge, but it also lengthens the wheelbase so the blade is better positioned front to rear to average out the vertical movement of the machine. I have a 7 foot moldboard and my 763 on tires will easily penetrate into compact class 5.
You will see in most of the videos online the operators are running laser controlled units and have either all wheels or all the tracks on the ground. They can do that because the laser is adjusting the height of the blade between 500 to 1000 times per minute depending upon the rotational speed of the laser.
I quickly found that if I run mine with the front wheels at least 3 inches off the ground it is easier to make minor blade height adjustments by rolling or curling the Bobtach rather than trying to press both switches to lift or lower both blade cylinders.
Note that these units are not dozers. It seems that operators seem to think they are. The second and now third generations of these grader attachments are being built heavier and heavier. I have seen two units like mine that were twisted like a pretzel.

 

[mtgstuber]

I have one of the early models that was made by Palm for Bobcat. However I don't have a lot of hours operating it.
When operating it, you lower the boom and roll the Bobtach enough to lift the front tires a couple inches off the ground. This not only transfers weight to the cutting edge, but it also lengthens the wheelbase so the blade is better positioned front to rear to average out the vertical movement of the machine. I have a 7 foot moldboard and my 763 on tires will easily penetrate into compact class 5.
You will see in most of the videos online the operators are running laser controlled units and have either all wheels or all the tracks on the ground. They can do that because the laser is adjusting the height of the blade between 500 to 1000 times per minute depending upon the rotational speed of the laser.
I quickly found that if I run mine with the front wheels at least 3 inches off the ground it is easier to make minor blade height adjustments by rolling or curling the Bobtach rather than trying to press both switches to lift or lower both blade cylinders.
Note that these units are not dozers. It seems that operators seem to think they are. The second and now third generations of these grader attachments are being built heavier and heavier. I have seen two units like mine that were twisted like a pretzel.

Thanks. That's very helpful. I've already got a bulldozer, so I don't need to use it as one. I have some additional questions. TriHonu, you mention not having a lot of hour n your unit. Is there a reason why? I notice the front wheels are on swivels. Do you find that just two wheels in the back are sufficient for steering? How much steering is driven by the blade? Bobcat only offers by the side shift in the larger units, which they claim are only supported by the 750 (or bigger) units. Has the manual side shift worked okay for you? How much of a pain is it?

 

[TriHonu]

Thanks. That's very helpful. I've already got a bulldozer, so I don't need to use it as one. I have some additional questions. TriHonu, you mention not having a lot of hour n your unit. Is there a reason why? I notice the front wheels are on swivels. Do you find that just two wheels in the back are sufficient for steering? How much steering is driven by the blade? Bobcat only offers by the side shift in the larger units, which they claim are only supported by the 750 (or bigger) units. Has the manual side shift worked okay for you? How much of a pain is it?

Quote: mtgstuber - 'TriHonu, you mention not having a lot of hours on your unit. Is there a reason why?'

I bought this attachment mostly because I just wanted one. I got it for a good price because it needed work.
It was a trade-in at a dealer from a cement contractor that specialized in curb and gutter. It had been set up for auto string-line tracking with a sonic tracker. It was all there but needed a wheel yoke straightened, the A-frame wear block replaced, new front axle pivot bushing and pin and I had to fab and wire a control box to manually operate the valves.
I'm retired and just have not had many jobs where I could really take advantage of it. I had no experience operating a grader when I bought it. I'm still learning, and it takes a lot of concentration to manually operate one of these. My projected uses were residential driveway and drainage grading.
These units really shine when used to set final grade for flat work with laser control. However with the cost of the grader, receivers and level you better be saving a lot of concrete to justify the investment.

Quote: mtgstuber - 'I notice the front wheels are on swivels. Do you find that just two wheels in the back are sufficient for steering? How much steering is driven by the blade?'

It depends upon the soil type and cut. If you have a lot of angle on the blade and are trying to pull in shoulders you will need to have all four wheels on the ground. If you have the cut mostly on the toe you will also have some steering issues (and blade vibration). It is just the nature of the design with casters up front. Spreading/cutting granular and reasonable cuts using most of the blade width was not an issue. Palm offered an optional scarifier for its grader which seems to imply that they are designed for loose soil.
If you have difficult soil, I wouldn't expect any small grader to operate very well, if at all. The possibility of damaging these units under these conditions happens. I have seen two units like mine where the moldboard was bent. I don't know if they caught something or just a lot of heavy cutting. My blade was significantly reinforced at the top of the frog (not factory). I assume the previous owner found the same issues. Mine has also been reinforced at a number of places on the frame.

Quote: mtgstuber - 'Bobcat only offers side shift in the larger units, which they claim are only supported by the 750 (or bigger) units. Has the manual side shift worked okay for you? How much of a pain is it?'

I have not needed the side shift. The previous owner lengthened the blade. With the circle fully rotated, I have set it with the left toe just outside the loader wheels and the right side long.
I have not tried to operate it with the blade shifted all the way to one side. With tires I thought it would have too much leverage making steering difficult at best.
On mine you have to loosen four nuts and you can easily slide the blade if the support is clean. The back of the blade is like a square tube with the side toward the loader having a slot cut down the middle of the tube. (If you pack dirt in the slot, moving the blade will be difficult since the bolts must slide in the slot.)
When I bought mine that tube was packed solid. I removed the blade and used a big screwdriver and then a pressure washer to get all the gravel out of there.
If you think you will be adjusting the side shift, I would look closely at how the blade mounts on the new models. If it can get jammed with dirt, it surely will...

 

[Boulder]

Thanks. That's very helpful. I've already got a bulldozer, so I don't need to use it as one. I have some additional questions. TriHonu, you mention not having a lot of hour n your unit. Is there a reason why? I notice the front wheels are on swivels. Do you find that just two wheels in the back are sufficient for steering? How much steering is driven by the blade? Bobcat only offers by the side shift in the larger units, which they claim are only supported by the 750 (or bigger) units. Has the manual side shift worked okay for you? How much of a pain is it?

I've got the 108'' Bobcat grader attachment that I run on my T300 and will be soon on a T870 as well. These are really heavily built and I use it a lot to trim up parking lots, driveways and trim ditches. You can roll as big a ridge as the bobcat can push. My skid steer usually starts veering off before I'm ready to quit cutting!