fix for grader blade adjustment problem?

[2manyrocks]

I have a slider type grader blade that locks in place with a bolt on each side of the center pivot. The blade can be extended out or in and can be pitched up and down by adjusting these two bolts in addition to the normal angle adjustment on the center pivot.

I'm having a problem with the pitch adjustment moving. Every time I set the blade to create a pitch, it moves out of position during grading. Since this photo was taken, I have added gauge wheels, but I still have this problem.

Any ideas how to fabricate something that will hold this thing in position and still be able to adjust the blade? I don't want to add hydraulics and don't want to weld it in one position.

 

[MtnViewRanch]

Maybe if you could get bigger bolts in there, you would be able to get them tighter, and that might be enough to hold it in place. Are there lock washers on the bolts? Can't think of anything else right now.

Good luck

 

[Trucker1]

From looking at pic, are those slotted holes for your pitch adjustment? If they are, I would weld the washers on in a zero pitch position, then use the side link to adjust pitch. You would still be able to loosen bolts to slide the blade left/right, in/out.

 

[KML]

I have an almost identical blade and haven't had a problem with it moving. I do use a 1/2" breaker bar to tighten the bolts though
The first thing I would try is to remove the rust from between the two surfaces. I really think that would help.

If it doesn't and you don't want to get too involved I'd drill a hole above and below the bolt heads that lock it in place and put in 4 bolts (2 on each side). You could either thread the channel itself or tack weld a nut (better). Then after you set it where you want it and tighten the bolts you run in the top and bottom bolts to lock it in place.

I know, my drawing suck, but this is the idea..

 

[2manyrocks]

You've got me wondering if this washer is part of the problem?

 

[wedge40]

I have an almost identical blade and haven't had a problem with it moving. I do use a 1/2" breaker bar to tighten the bolts though
The first thing I would try is to remove the rust from between the two surfaces. I really think that would help.

If it doesn't and you don't want to get too involved I'd drill a hole above and below the bolt heads that lock it in place and put in 4 bolts (2 on each side). You could either thread the channel itself or tack weld a nut (better). Then after you set it where you want it and tighten the bolts you run in the top and bottom bolts to lock it in place.

I know, my drawing suck, but this is the idea..

I was trying to figure out something similar.. Very good idea. I'll have to file this away if I ever need something like this.
By the way, your drawing is perfect.

Wedge

 

[3RRL]

I have an almost identical blade and haven't had a problem with it moving. I do use a 1/2" breaker bar to tighten the bolts though
The first thing I would try is to remove the rust from between the two surfaces. I really think that would help.

If it doesn't and you don't want to get too involved I'd drill a hole above and below the bolt heads that lock it in place and put in 4 bolts (2 on each side). You could either thread the channel itself or tack weld a nut (better). Then after you set it where you want it and tighten the bolts you run in the top and bottom bolts to lock it in place.

I know, my drawing suck, but this is the idea..

Yes, that is a very good idea KLM.
In fact, you could try just 2 bolts just like that idea, one on top of each nut on (one on each side) and use a double nut to lock that vertical bolt in position. Tighten one and loosen the other to get your pitch. It should work.
Four bolts would be better, but you might try 2 to start out. If they slip off the nut, add the other two to the bottom. In any case, I would still double nut for a lock.

 

[john_bud]

Simpler would be to get two pieces of channel about 4-5" long, drill two holes in each. Then put one on each side and bolt down like bookends. Then they will stop the original ones from sliding.

jb

 

[3RRL]

Would that be adjustable for pitch?

 

[2manyrocks]

If I understand John Bud's idea correctly, it would be adjustable. I think he means I could bolt a piece of channel on each side in the existing slot on the grader blade to help further lockup the two existing bolts.