I'm trying to visualize how this would be different from a 3PH post hole digger with a downforce cylinder.
Got a LARGE pizza you want to cut?
- Thread starter Mochanic
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David Page
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Equipment
1974 L260, 6" bush hog, subsoiler, spring tooth harrow, boom pole, 2 bottom plow
Subsoiler, I have one, as D2Cat says the shear pin does the job. Its handy for pulling or flipping rocks out of the ground.
Mochanic, what is the diameter of the cutting wheel? You can limit the reaction force of a hard impact by limiting the depth of the cutting wheel. Set the depth so you never exceed ~25% of the diameter. It will help roll the wheel over the object and not stop the tractor.
Keeping the speed down on the tractor will help also. Jeff
Keeping the speed down on the tractor will help also. Jeff
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
A down force kit does not put upward force on the tractors top link.
https://www.youtube.com/watch?v=xPRqoGyyA_Q
It looks like the down force cylinder on a post hole digger puts a mostly horizontal force against the top link attachment point on the tractor. That would be fairly similar to the force applied by a roto tiller or most other implements when operating.
I'm guessing that the damage shown in the Youtube video may have been caused by a bouncing raised implement. Visualize bouncing across a rough field with a bush hog in the raised position putting tension rather than compression on the top link. The cracked tractor casting more than likely happened in tension rather than compression.
I had an Allis 720 tractor with hydraulic down force on the 3PH which was very handy at times and applying too much would simply cause immediate loss of traction. I do have to agree, however, that the nearly vertical force applied to the 3PH top link attachment point with the "Doggie Ditcher" is not applied with normal 3PH applications.
With regard to the OP's invention, I would advise using with caution and common sense of which he seems to be in possession.
I know, my grammar is a bit suspect.Edit: I happened to come across this variation of a 3PH down force kit offered by Deere:
https://crossimplement.com/news-and-updates/article/2014/12/3-point-hitch-downforce-kit
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All the post hole diggers with a solid support (tube, i-beam, whatever) from the top link bracket out to the suspended gearbox and auger create a upward force as the weight pivots at the hoop. The EA down force kit will increase the upward force at the tractor 2 -3 times the 500 lbs down force plus the weight of the gearbox/auger.
The support tube is a leaver and leavers can multiply force on the short end.
On the other hand a boom pole does not lift because of the top link has a pivot on both ends. The force is transmitted in line with the top link.
Jeff
The support tube is a leaver and leavers can multiply force on the short end.
On the other hand a boom pole does not lift because of the top link has a pivot on both ends. The force is transmitted in line with the top link.
Jeff
It is true that the "solid support (tube, i-beam, whatever)" creates an upward force on the top link bracket but only when the PHD is suspended in the out of ground non working mode.
The typical down force kit, however, applies very different forces when digging a posthole. A parallel linkage is formed between the vertical yoke, the solid support tube and the lower 3PH arms of the tractor with force input applied via the hydraulic cylinder.
The parallel linkage applies tractor weight to the auger through tension and compression forces in the horizontal members of the linkage. There is no pure vertical force (up or down) applied to the tractor top link bracket in this scenario.
If you want to see most of the problems that I have already encountered and conquered read the 4 posts on this thread and you will see exactly why I bought the wrong color tractor. (and NO not a single one of these problems were in any way my fault!)
http://www.orangetractortalks.com/forums/showthread.php?t=40083&page=4 posts 33-36
10.5", but the max cutting depth is 3.75".
There is NO chance that anything this wheels could ever encounter would stop the tractor at the wheels max cutting depth. Also it's used in low gear with engine rpm's less than 2000, so speed is already pretty slow.
Mochanic, I went back and looked at the pictures you posted in the link above. When did all these problems occur? If these pictures were taken in the first few months of ownership you should have been back to the dealer and determined the cause then.
It's an 8 year old tractor and looks like it's spent it's life in saltwater. The parts with extreme rust indicate problems way outside of Kubota Corporation's control. What do you think caused the seat pan to deteriorate the way it did?
It's an 8 year old tractor and looks like it's spent it's life in saltwater. The parts with extreme rust indicate problems way outside of Kubota Corporation's control. What do you think caused the seat pan to deteriorate the way it did?
I don't understand how some of you guys can't seem to fathom how low the stresses are on this attachment. ONCE again, there is NO, ZIP, ZILCH, banging, beating, jerking, hitting, forces on this very simply attachment, it simply cuts a very shallow 1" wide trench by parting the dirt away from each side of the very sharp cutting wheel up to 3.75" deep.
If you want to see some crazy forces, hook a 48" rotary tiller or an 18" deep subsoiler up to a BX series. Honestly even I am amazed neither of these have broken parts off the tractor! IF (HUGE IF) something were going to break the tractor's 3 point, it would most definitely be the tiller when it encounters a root!
Again, the BX tractor does not weigh nearly enough to hurt the top mount. A level scoop of sand in the FEL bucket will damn near lift the rear wheels off the ground if you don't have counter weights in the rear, so it obviously doesn't need much to pick the ass end up. Nothing that this cutting wheel ever rolls over is going to break the tractor before it simply lifts the wheels off the ground!!!
Now all of you wannabe engineers take your propeller hats off and put your cowboy hat back on and relax, it will be okay!
I won't dare show you my huge 3pt sprayer that I designed and built! You guys might have a heart attack, lol...
If you want to see some crazy forces, hook a 48" rotary tiller or an 18" deep subsoiler up to a BX series. Honestly even I am amazed neither of these have broken parts off the tractor! IF (HUGE IF) something were going to break the tractor's 3 point, it would most definitely be the tiller when it encounters a root!
Again, the BX tractor does not weigh nearly enough to hurt the top mount. A level scoop of sand in the FEL bucket will damn near lift the rear wheels off the ground if you don't have counter weights in the rear, so it obviously doesn't need much to pick the ass end up. Nothing that this cutting wheel ever rolls over is going to break the tractor before it simply lifts the wheels off the ground!!!
Now all of you wannabe engineers take your propeller hats off and put your cowboy hat back on and relax, it will be okay!
I won't dare show you my huge 3pt sprayer that I designed and built! You guys might have a heart attack, lol...
They mostly all occurred within 3yrs or less. And trust me I was constantly dealing with warranty issues. The dealer replaced the rear fender, and floor pan under warranty. Even the brand new parts were starting to see problems right away. You could see that there was simply no paint prep done and the paint just didn't want to stick. You could peel off a sheet of paint up to about 6" long within 6 months of them replacing the parts! Nothing but orange paint, NO PRIMER whatsoever! I haven't had any issues with the same parts that I had powder coated from several years ago, or from any parts that I personally took off, sandblasted and painted myself with nothing more than cheap rustoleum rattle can paint.
This tractor has never seen saltwater, and nothing else that I own that isn't orange rusts like this, so I have to believe that the problem is completely related to piss poor paint preparations.
I am NOT the only one having issues with rusting Kubota's.
http://www.orangetractortalks.com/forums/showthread.php?t=36003
https://www.tractorbynet.com/forums/kubota-owning-operating/372860-i-bought-brand-new-tractor-3.html
Do a quick google search and you will find plenty more.