3-Point Hitch Rear Blade and 3 point hitch adjustment question

[Chuck on lake]

I simply don't understand the geometry of a three point hitch. I have a JD 3720 with a Buhler Farm King rear blade that has hydraulic angle control. I also have a JD iMatch hitch. When I adjust the upper lift arm so that the iMatch is plumb the beam to the rear blade is level. I adjust the right lift arm so that the blade is also level when it isn't angled. Now if I use the hydraulic angle feature to angle the blade one way or the other the blade is no longer level but is higher at one end than the other. Is is necessary to readjust the side left arm every time I change the blade angle?

Just can't figure it out - Thanks

Chuck

 

[glc24]

Hey Chuck
I'm betting the cylinders for the blade angle aren't horizontally level. They would have to be at a slight angle for the blade to do what it's doing.
Things like this is what a Top and Tilt would be good for.:thumbsup:

Can you post a couple pics?

Greg

 

[rus_geek]

Try this. Angle the blade to one side and then adjust the top link to make the blade level (ignore the beam). It should then stay level throughout the rotation. The side link should only be adjusted to level the blade when it's straight.

-rus-

 

[LD1]

This maybe a simple answer:thumbsup:

First, the cylinder (as mentioned) isnt level with the blade. But that doesnt matter whatsoever. Provided there isnt an astronomical amount of slop in the kingpin (blade pivot).

On to business.

Forget the i-match as a reference for plumb. Usually the kingpin (large pin the blade rotates around) is 90 degrees to the frame-work of the blade itself.

First Makesure the frame is level (when the tractor is level ofcourse). This will make the kingpin vertical length-wise. Adjust this with the toplink.

Second, makesure the blade is level left to right. This will ensure that the kingpin is level in the left-to-right direction.

Now those two steps "should" make the kingpin perfectally plumb to the ground in all directions and will make the blade rotate level.

A couple of other notes:

1. Do these level checks with the blade on the ground.
2. The 3PH is NOT a perfect parallelogram. So as the blade raises the kingpin will no longer be level front to back even though it is level left-to-right.

So if you are making these adjustments with the blade raised all the way, by the time it is lowered, the kingpin is no longer plumb.

I suspect that is your problem.

If that doesnt solve your issues, you probabally have something bent or tweaked

 

[boggen]

what are you trying to do? to want a level blade? there only a few reasons i can think of, but there are also plenty of other reasons for wanting blade off level some as well.

the times i can think of wanting a level blade, is when on pavement or like driveway and removing snow. maybe a rock driveway or dirt lane to smooth out ruts and like.

but on rock driveway's / dirt lanes / paths through woods. you will more likely want to create a "crown" in middle (slightly higher in middle than at sides). or slope the entire driveway around a corner or along a hill to one side. so water drains off the driveway / lane / path through woods.

or put even more angle to cut ditches out.

===========================
imatch quick hitch

everythingattachments if they have a video for rear blade, it would be your best bet for how to use rear blade / adjust rear blade for different things. vs trying to go through youtube videos.

not the best pictures / diagrams below. but hopefully gives you a picture worth a 1000 words type a thing. though it is lacking a lot. (click in below attach pictures to enlarge them.

 

[Chuck on lake]

Try this. Angle the blade to one side and then adjust the top link to make the blade level (ignore the beam). It should then stay level throughout the rotation. The side link should only be adjusted to level the blade when it's straight.

-rus-

Thanks so much. This is the solution I was looking for. It never entered my mind to adjust the top link. I was always fooling with the side link trying to solve it. boggen to answer your question yes I need a level but angled blade for snow removal and yes I do use a bevel to form a crown when repairing and grading our one mile gravel road in the summer. I REALLY appreciate everyone's answers and suggestions. Thanks again!

Chuck