Homemade Hydraulic angle on Rear Blade

[Craig Clayton]

Gentlemen
I have more pictures of the blade but can not figure out how to add them to the original set of pictures, so I am dumping them in as a reply.

 

[/pine]

Just curious as I'm all for anything that keeps me in the seat...

obviously this is no problem for moving snow...but what about working on gravel and rocky roads? Does the cylinder not offer the only resistance?

Is the cylinder/lines not vulnerable to shock pressure? will a check valve offer a solution?

 

[Craig Clayton]

Dear /pine
The cylinder is the only resistance, that is why I leave the spool valve in neutral when working hard. I will change the angle when moving snow, but we all know that wet packed snow can be as hard as gravel so that is when I leave the spool locked. what I have found is when I am plowing heavy snow and the tractor starts to move crab style I can change the blade to less than 45 degrees to maybe 30 degrees and it prevents side slip. When I get to the end of the drive and I turn right I start to angle forward and do not leave a ridge, then as I am coming out of the turn I angle back to 45. I have a gravel drive and I work the blade hard but with care. Dozers under hard load do not angle either.
Craig Clayton

 

[Craig Clayton]

Dear spo307
Thank you for being interested in this idea. The method that I used to develope the lenghts of the cylinder was by trial and error. As I do not know what movement you require on your machine I will quote my rear blade.
I raised the blade on the tractor, off of the ground so that it could swing easily. I measured the closed lenght of the cylinder, and the extended length of the cylinder. I used a simple wooded stick to be the heavy angle iron on the back. I swung the blade to left 45 degrees and used tape to guess what might look good. I swung the blade to the right 45 degrees and keeping the same pivot points in mind used the extended lenght of the cylinder. This will show very quickly show what might bind up or pinch.
If things are looking good repeat the exercise and try adjusting the pivot points slightly. You might need a longer or shorter cylinder. It costing nothing for a tape measure and a stick of wood and a few pencil marks. If the design is looking good think about the forces and do they make sence. Then you vice grip the stick in place and the tape is the hydraulic cylinder. If things are looking good build it using the pivot points that are working for your machine.
Make it strong, if commonsence is borderline say 1/4" steel, I go to 1/2" steel if I have no real point of reference.
Craig Clayton

 

[J_J]

Just curious as I'm all for anything that keeps me in the seat...

obviously this is no problem for moving snow...but what about working on gravel and rocky roads? Does the cylinder not offer the only resistance?

Is the cylinder/lines not vulnerable to shock pressure? will a check valve offer a solution?

What you are saying is true. If the blade should grab a large rock, that cyl could generate a large shock pulse that might blow a fitting, hose or valve unless the work ports have a relief, and the relief might not be quick enough. There are different kinds of relief that are available. Some might be quicker than others.

 

[Craig Clayton]

Dear J_J
I see some concern about the forces when hooking big rocks. Yes, something might or will break. A dozer mechanic who knows said on a 6 way blade if you move the spool valve at maximum pusing load you can ( bugle ) a cylinder,that is why you leave them locked.
My first cylinder was much older and had a bad end, but it was on in such a way that the forces caused no problems for the first 3 weeks. Meaning I remembered to not angle under load. Well one night when moving snow and I was having too much fun I forgot my own rule and I move the valve causing pressure on the bad end. BOOM oil on the snow,I finished with the mechanical pin.
Saturday I had a new (import cylinder ) and welded on the new mounting blocks in almost the exact location as the old cylinder.
I did some ball park numbers 3 feet at 500LBS =1500FTLBS torque.
1500x 3 =4500 push on the cylinder end.
2 1/2" cylinder at 2000 psi can push = 9812.5 LBS.
If the shock load exceeds the safety factor of the hoses/cylinder/ bolts/ angle iron you will be picking the pieces.
Craig Clayton

 

[HSSC]

A cushion valve in line will solve the shock load issue.

 

[mad_planter]

There was a thread on here last year where a guy build one that would rotate all the way around (may 3RRL ??). I think it had to do with position of the cylinder and length of cylinder travel. When the cylinder was extended long, the blade would rotate all the way around. Then draw the cylinder in some to set the angle. Do it again, and it'd flip around again. It was pretty sweet setup accomplished with just one cylinder.

Must have been set up like the piston/wheel arrangement on a old steam engine.

 

[MtnViewRanch]

There was a thread on here last year where a guy build one that would rotate all the way around (may 3RRL ??). I think it had to do with position of the cylinder and length of cylinder travel. When the cylinder was extended long, the blade would rotate all the way around. Then draw the cylinder in some to set the angle. Do it again, and it'd flip around again. It was pretty sweet setup accomplished with just one cylinder.

Here's that thread. An updated video on post 238.


Landscape Rake Build - Page 24 - TractorByNet.com

 

[mjncad]

There are changes I would like to make but it works just fine.
Craig Clayton

Anything to make life easier is a good thing in my book.

There was a thread on here last year where a guy build one that would rotate all the way around (may 3RRL ??). I think it had to do with position of the cylinder and length of cylinder travel. When the cylinder was extended long, the blade would rotate all the way around. Then draw the cylinder in some to set the angle. Do it again, and it'd flip around again. It was pretty sweet setup accomplished with just one cylinder.

You might be thinking Gugliols rear blade where he used a hydraulic motor and gearbox that he and 3RRL made for 360-degree rotation. It uses a hydraulic cylinder for offset. It's a real slick setup.

What you are saying is true. If the blade should grab a large rock, that cyl could generate a large shock pulse that might blow a fitting, hose or valve unless the work ports have a relief, and the relief might not be quick enough. There are different kinds of relief that are available. Some might be quicker than others.

Would a 'Double Pilot Operated Check Valve' solve this problem? Or would it just localize the shock the cylinder and check valve? I see another poster suggested a cushion valve. What's you thoughts on that?