Three point hitch draft control M4700

[Complete Turf Care]

Did you ever find out the problem with this

No I have not. I wish I could figure it out, but I don't want to spend a lot of money on this tractor. I have 3 other tractors that I use on a regular basis, and this one does not get used much at all.

I'm afraid that if I bring it to a Kubota dealer, it may get quiet expensive to repair.

 

[JWR]

Draft control tries to keep a constant pull on the tractor by varying the depth of the pulled implement, with the position control setting the maximum depth for the implement.

I do not understand the function that way. I thought the function of Draft control was to maintain and allow adjustment of even plowing depth, not to manage tractor pull. Makes no sense to me to pamper the tractor when it is intended to be your slave, not your master. Of course, if you run into an issue of losing traction that is a reason to set the plowing depth more shallow, to me the secondary issue. Just viewpoint I suppose.

 

[LouNY]

From a New Holland brochure.

Mechanical draft control simplicity​

Delta and Plus models feature a simple mechanical draft control (MDC) system that uses lower-link draft sensing to precisely maintain draft loads while working in the field with three-point-mounted implements. (MDC is not available on the T6070.) Models with MDC also feature the convenient Lift-O-Matic™ system that allows you to raise or lower an implement with the touch of a button, without altering the draft settings—a real time-saver during headland turns.

Added EDC benefits​

Electronic Draft Control (EDC) allows for precise, automatic control of three-point-mounted implements using lower link draft sensing to maintain a constant load on the hitch through changing soil conditions. T6000 tractors equipped with electronic draft control also get the convenience of fast hitch raise/lower control both inside the cab and on the rear fenders. Dynamic Ride Control is also standard equipment on EDCequipped tractors to help prevent three-point-mounted implements from “bouncing” on the rear hitch during transport, giving you greater control and a more comfortable ride.

 

[npalen]

I view draft control as a way of cheating when your tractor is not capable of maintaining even tillage depth due to horsepower and traction limitations. If you set your 3PH to a 6" depth of cut but the tractor can only handle 4" depth thru 90% of the field, what is the point?

Yes, there are situations where going thru a ditch or over a rise where draft control has its place.

 

[JWR]

npalen: traditional draft control had nothing to do with tractor capability limitations due to horsepower or traction. It had everything to do with the very practical problem faced by sod busters. Namely the soil strength (tensile and compressive) varies a lot. With the plow tip shaped to nose further into the soil as it pulls the soil upward past the plowshare, the tendency (in typical 1950 tilling) was the darn plow wanting to sink itself deeper than desired at times and then float higher than desired at times --- defeating the object of a getting an evenly plowed field. Sometimes it was diving under hard, heavy patches of clay or rocks. Other times it was tending to float on soft almost fluid soil. That made for erratic unevenly plowed fields, uneven depth for soil nutrients and seeding, etc. Some pretty good genius of the day invented Draft Control using up/down axis forces (only, not fore and aft) in a feedback loop to maintain stable and near constant plowing depth. That invention is used in many places today (on everything from very small utility tractors to giant machines) but most of us tractor users never use it. I wager less than 5% of utility tractors sold today will ever be used with draft control. Most people are just not plowing.
LouNY: EDC and who knows what all varieties of complex and more sophisticated feedback systems can be made/sold/used like what you found in the modern New Holland literature. Great. More power to 'em. But that is not the basic Draft Control we were all talking about.

 

[LouNY]

npalen: traditional draft control had nothing to do with tractor capability limitations due to horsepower or traction. It had everything to do with the very practical problem faced by sod busters. Namely the soil strength (tensile and compressive) varies a lot. With the plow tip shaped to nose further into the soil as it pulls the soil upward past the plowshare, the tendency (in typical 1950 tilling) was the darn plow wanting to sink itself deeper than desired at times and then float higher than desired at times --- defeating the object of a getting an evenly plowed field. Sometimes it was diving under hard, heavy patches of clay or rocks. Other times it was tending to float on soft almost fluid soil. That made for erratic unevenly plowed fields, uneven depth for soil nutrients and seeding, etc. Some pretty good genius of the day invented Draft Control using up/down axis forces (only, not fore and aft) in a feedback loop to maintain stable and near constant plowing depth. That invention is used in many places today (on everything from very small utility tractors to giant machines) but most of us tractor users never use it. I wager less than 5% of utility tractors sold today will ever be used with draft control. Most people are just not plowing.
LouNY: EDC and who knows what all varieties of complex and more sophisticated feedback systems can be made/sold/used like what you found in the modern New Holland literature. Great. More power to 'em. But that is not the basic Draft Control we were all talking about.

It works the same way, just not as precisely. The older mechanical systems were sensing using the top link attachment point on the tractor. It was still adjusting to maintain a constant pull on the tractor.

 

[npalen]

npalen: traditional draft control had nothing to do with tractor capability limitations due to horsepower or traction. It had everything to do with the very practical problem faced by sod busters. Namely the soil strength (tensile and compressive) varies a lot. With the plow tip shaped to nose further into the soil as it pulls the soil upward past the plowshare, the tendency (in typical 1950 tilling) was the darn plow wanting to sink itself deeper than desired at times and then float higher than desired at times --- defeating the object of a getting an evenly plowed field. Sometimes it was diving under hard, heavy patches of clay or rocks. Other times it was tending to float on soft almost fluid soil. That made for erratic unevenly plowed fields, uneven depth for soil nutrients and seeding, etc. Some pretty good genius of the day invented Draft Control using up/down axis forces (only, not fore and aft) in a feedback loop to maintain stable and near constant plowing depth. That invention is used in many places today (on everything from very small utility tractors to giant machines) but most of us tractor users never use it. I wager less than 5% of utility tractors sold today will ever be used with draft control. Most people are just not plowing.
LouNY: EDC and who knows what all varieties of complex and more sophisticated feedback systems can be made/sold/used like what you found in the modern New Holland literature. Great. More power to 'em. But that is not the basic Draft Control we were all talking about.

Draft Control using up/down axis forces (only, not fore and aft)
Is this some different type of draft control you mention? The Harry Ferguson draft control used fore/aft forces to pivot the implement causing it to compress the top link and actuate the draft control.

As far as getting the plow to penetrate, the draft control cannot control that as it has no down pressure on the 3PH. With that said I've never experienced a plow trying to float on "soft almost fluid soil".

 

[JWR]

Downward force is provided by the nose of the plow pointing downward and tending to pull the plow deeper and deeper depending on soil density, strength, etc. Back in horse-drawn plowing days, the front wheel was there to prevent the plow from "burying itself" too deep. By sensing vertical position, Draft Control regulates the depth of soil penetration by the plow with the goal of constant depth. Draft IS depth. Thus Draft control inherently means depth control. That's traditional Draft Control. Over decades of use, more complex control systems have of course evolved like the EDC mentioned by LouNY in post #83 in a claim to fame for New Holland. There are many variations.

 

[npalen]

Sorry, but I think you are confusing draft as a nautical term with draft as a farming term. Draft, as a farming term is the horizontal force required to pull an implement through the soil.
The draft on a 3PH is controlled by raising and lowering the implement by the draft control feature as the implement encounters variation is soil. The position control on a 3PH simply establishes a baseline depth.

Draft (hull) - Wikipedia

en.wikipedia.org

Agricultural Machinery Management (ACIS)

This is a document on , one of a series of documents on cotton crop management. Provided by the University of Arizona.

cals.arizona.edu

 

[kthompson]

I admit did not read all these post but what came to me mind was the knob locking the lift arms up was what was hold it up, maybe.
I have a M6800 and the draft is not that great to me on it. It does work but very sensitive.