Backhoe Added a ripper to my Woods BH90x: Trees beware

[IslandTractor]

Teeth would be an improvement but what I think would be best are Y shaped protrusions mid blade front and back. Those would snag the roots and either tear them or cut a chunk out. Teeth would act like a serrated knife and saw at the roots. The point is that sawing is not necessary as the ripper/BH has plenty of power to rip the root apart if it can get a grip. The plain ripper only fails when the root is able to ride up the blade. It is more a matter of the root being "plastic" and just moving with the blade than the blade/BH not having the power to cut. I think of a saw as working when something is too big to cut in one swipe but here the issue is more needing to snag the thing so it cannot ride up the blade. An obstruction mid blade front and back would do it IMO.

I have welded a piece of drill pipe steel mid blade both sides. No empirical data yet. Maybe in January if the winter continues to be mild up here.

 

[Coyote machine]

IT,
Can you put a pic or two of your mods on the site here so I can look at them; and possibly a rough drawing of what you mean by the "Y" shaped protrusions and where you'd think they would be best suited to the front and back of the blade?
I'm looking to have Bob do whatever mods to the ripper now that you and others have done some in field testing.
We have some time to refine the process because he's up to his elbows in snowplows, etc. 'till February.
I don't quite understand what the need is for anything on the back side of the blade? Seems to me all the curl force is applied when the tooth is used to pull toward the hoe OP and that the teeth, or Y object would provide the extra measure to rip/tear on the slippery root's backside instead of being able to ride up the smooth metal from the hardened tooth toward the hoe's ripper pins? No?
Any input would be appreciated. I plan to do extensive 'crash test dummie' field testing of whatever the gen 2 ripper ends up being, and want MIE to be able, as well as me and future buyers to benefit from any incremental changes you experienced operators can toss back at us.
I'm open to any and all suggestions so please keep them coming, IT and others.:thumbsup:

 

[IslandTractor]

I thought I took some photos of the modifications but cannot find them now. I've used Paint to sketch in where I welding the drill pipe sections on a photo of the original ripper below. I had originally planned to do something more like what Nickel Plate did but my welding instructor had this high grade steel drilling pipe on his truck so we cut a few pieces and I used that. The drill pipe is about 1.5 inches in diameter with half inch thick walls and I used about a two inch long piece which was simply welded to the ripper blade front and back. Rough position shown on the marked up photo. The drill pipe was laid parallel to the blade edge so the cross section of the pipe was facing both forward and backward. The "cutting edge" is therefore just an abrasive saw cut through the drill pipe.

Again, my idea was mostly to 1) grab the root so it could not slide up or down the ripper blade so the BH force could be applied. 2) besides catching the root, if the root was too thick to simply break, the drill pipe would tear a 1.5 inch chunk out of the root as the ripper moved up or down. I would guess that there are very few roots that would not break after a pass or two with the modified ripper but I haven't put it into action yet. Usually I cut with the concave side of the ripper but there are instances where it is useful to use a "backhand" cut and that is the reason for having the modification on both front and back sides.

Sorry for the crappy artwork.

 

[Coyote machine]

Island,
Thanks for the quick markup on the photo. Color by numbers?
I guess I have to ask why just cutting recesses, (teeth) into the front, concave side of the existing tooth and possibly on the back side too wouldn't accomplish the same thing and maybe 'sooner', in that wherever the root catches it will start the rip/tearing process without having to run into the pipe pieces, for instance?
Here's what I envision, not a sawing action so much as a root catching the first tooth that it encounters, and once caught then the OP applies pressure by curling the bucket until the root gives up. Teeth similar to what MIE supplies on their Bhoe thumbs.
So let me see if I have the pipe attachment idea down. You cut a slit in the vertical piece of pipe and then weld the slit side to each side of the concave and convex edge of the ripper?
What about the "Y" piece you mentioned, what would it look like, and where would you attach it? Would it be in the same location as the pipe pieces you drew on the pic of the ripper?
What would be the advantage of the Y over say the pipe, or teeth recessed into the leading convex/concave edge of the ripper?

Thanks,

CM

 

[IslandTractor]

CM, I understand your question. Of course I don't know empirically whether a ripper with saw teeth protusions would not work as well or better than what I fabricated. And, what I put together was largely determined by materials at hand which is far different than MIE has available (to say nothing of the huge gap in fabrication skill).

First a clarification. I think from your last post that you think I cut the drill pipe longitudinally before welding it to the ripper blade face. I did not. What I welded to the ripper was simply a "chunk" or piece of the drill pipe, a complete, round section about two inches long. Water would still flow through it. I tacked it to the ripper blade edge and then welded in fillets to support it in place. So, the drill pipe section is roughly 1.5 inches proud of the ripper blade edge. Looks like crap but it has a full circle of sharp edges that are perpendicular to the main ripper blade and protrude above the blade. Think meat hook.

A saw type blade might well accomplish the same thing as I think my cobbled together, butt ugly modification. However it seems to me that the two modifications may behave a bit differently. As you note, a saw type modification would cut against the root even as the root started to slide across the ripper and would therefore nip at the root multiple times (however many teeth MIE cuts into the blade) as the ripper rubs against the root. There would be pressure against the root too so as the saw action cut the root it would pretty quickly reach a point where the root would just break. Understood. While I don't doubt that would be a significant improvement, what I am a bit concerned about with the saw approach is that you don't really want to saw back and forth as that motion is hard to do with a backhoe. What you want is for the thing to rip through in the first curl. If the teeth are cut so there is a 45 degree angle cutting into the root I don't know if that will snag the root or allow it to pass over the top with just a 1/4 inch or 1/2 inch slice into the root. Snagging is desirable IMO as we pretty much know the ripper has the hydraulic force to break just about any root that can be held in place while that full curl force is applied to a 1 inch area. The idea behind both my modification and Nickel Plate's seems more to "snag" rather than "saw". The snagging will keep the root from riding up the blade and thereby that force will push the blade through the root. Imagine drawing a bread knife across your hand. It will take a sawing back and forth action as well as pressure to cut efficiently.

Remember this is all conjecture as we don't have empiric evidence but of the three proposed modifications (my pipe section, Nickel's single square blade protrusion and your proposed saw blade), I would put my money on Nickel's as most likely to work and be most easily fabricated too. Mine is really just a cobbled up field version of his and his works by pretty much the same principle as mine as far as I can see.

What we really need is a "test bed" ripper to work this out. A ripper with two mounting holes drilled along each side would permit different shapes (saw, square section, round section etc to be welded up attached to the top of a U shaped base) to be afixed by through bolting to the blade and then tested for efficiency at root ripping. If MIE were planning a production run of a hundred of these devices it might be worth doing that type of formal prototyping but in reality they will be doing one by one orders so that would be too big an investment of time and money. (Now, if MIE himself wants a ripper he could make such a model with different bolt on "teeth" and figure it out himself...hint, hint).

 

[beppington]

 

[IslandTractor]

Beppington wins the artist award! Yes, that is how the pipe sections are oriented. Thanks.

 

[Coyote machine]

IT, and others,

If not teeth by definition, then how about recesses in the blade to allow the root to slide into the recess and as it becomes locked into the recess the cutting edge slices into the root while curl force rips it to smithereenes?
It just occurred to me that a fish hook like barb, (enlarged for this purpose might do well?)
I will see if I can't 'draw' a sketch and then figure out how to post it- you haven't seen quality art until you see a sketch by me:laughing:

 

[nickel plate]

Another of my concerns about mounting a ripper blade to the leading edge of the tooth (I did mention in a previous post that there could be interference with my hydraulic thumb) is that it would be subject to abrasion by constantly slicing into undisturbed soil and rock thus wearing down and rounding off a lot faster than the ripper blade mounted to the trailing edge of the ripper tooth. At least the rear mounted blade has an advantage of traveling through soil that has been softened up and rock free thanks to the work from the leading edge of the ripper tooth. I fear the same result would occur to serrated teeth cut into the leading edge of the ripper tooth.
Again, I have not yet put the new tooth blade to task-that should happen in the spring.

As for adding a bladed appendage similar to mine via a bolt on procces, I gave that considerable thought too but decided against it for several reasons:

1. The nuts and bolt heads would have to be recessed or shielded to guard against abrasion resulting in rounding off or down and therefore becoming a wrench/removal problem.
2. Possible slop in the initial alignment fitting and drilling which would only get worse in time.
3. I don't have the right fabrication equipment.
4. The ripper tooth is for my personal use only so wear and tear should be at a minimum. If something really bad were to happen to the ripper blade, I'll grind it off.

 

[IslandTractor]

IT, and others,

If not teeth by definition, then how about recesses in the blade to allow the root to slide into the recess and as it becomes locked into the recess the cutting edge slices into the root while curl force rips it to smithereenes?
It just occurred to me that a fish hook like barb, (enlarged for this purpose might do well?)
I will see if I can't 'draw' a sketch and then figure out how to post it- you haven't seen quality art until you see a sketch by me:laughing:

The photo in the other JD ripper thread shows kinda what you are talking about at least on the back side. Cutting out a series of half moons out of the middle portion of the blade might well work. I don't know if it would be as effective as a protrusion at snagging the root but it seems to me it would have greater purchase than a saw blade.