Implements that pull on the drawbar and the world of good enough.

[mcmxi]

I bought a very well used Schafer disc harrow a couple of years ago for $1,200 and used it last summer on part of a new driveway project. It worked well but it was very sloppy on the drawbar. The coupler is worn out and I don't like the lack of a good jack (don't care for the current set up that requires a block) so this got me thinking about drawbar implements.

Dirt Dog makes something similar to the Schafer and they use the same type of coupler which allows articulation in the vertical plane, and the pin in the drawbar allows articulation in the horizontal plane. What this design doesn't allow for is rotation of the disc harrow relative to the tractor the way a typical trailer ball coupler does.

So does anyone see a problem with my cutting off the old, wallowed out coupler and upgrading to a Demco 2-5/16" coupler and adding a decent jack? I'd tow from a ball on the drawbar of course. From where I sit, it looks like this design is cheap and "good enough" and probably fine for flat ground. However, given the length of the harrow and its distance from the rear wheels of the tractor, I would think that there's a lot of stress on the coupler, pin and drawbar due to rotation of the plane that the harrow is on relative to the plane that the tractor's wheels are on ... if that makes sense. A well greased ball and coupler should run a lot smoother, last a lot longer and put less stress on the tractor and implement.

In addition, the tongue that the coupler is attached to pivots on a pin under the A frame, and the jack shown allows for vertical adjustment of the tongue to aid with hooking up to a tractor. I'm not a fan of that design either so if I go the Demco coupler/jack route I'll consider welding the tongue to the A frame and add plates and gussets as necessary.

 

[mcmxi]

Here's an example of a modern disc harrow made by Dirt Dog that's a much lighter version of the one I have but probably costs five times as much! Notice the coupler which is the same concept as the one on mine.

 

[mcmxi]

Thinking about this some more, the advantage of the coupler that's on the harrow is that there's very little chance of the harrow coming off the back of the tractor. I don't know the likelihood of a Demco coupler coming off the ball but I see the issue of coupler and hitch separation as being the main issue here.

I have a pintle hook on the back of the M1078 that rotates 360 degrees for off-road application but I wouldn't need such extreme articulation. I could easily add a lunette ring to the harrow (I have a bolt on one that I used to tow the Jeep behind the M1078) but I'd have to find or make a drawbar compatible pintle hook. It wouldn't be hard to make something that adapts the drawbar to a pintle hook such as the one shown below.

Option 1: Repair the coupler on the harrow
Option 2: Repair the coupler but make it able to rotate to reduce stress on the tractor and harrow
Option 3: Replace the coupler with a Demco 2-5/16" coupler
Option 4: Replace the coupler with a lunette ring and make an adapter to use a pintle hook on the drawbar (basically a clevis to four bolt adapter)

 

[North Idaho Wolfman]

As I was reading your first post I was thinking why don't you use a pintle hitch.
That hitch will let it articulate in every direction needed and it's STRONG!

Harbor freight has a killer price on a drop leg jack.

 

[GreensvilleJay]

3 decades ago to pull the $75 tandem discs, I had one clevis bolted to the tongue of the lead disc, then used a bigger 'clevis' to join the discs to the tractor drawbar. A true 'backyard bodge' but it's what I had at the time. Used it for 4-5 years until I got a welder.
if you connect left finger and thumb then interconnect to your right finger and thumb you can see that this allows for lots of up,down, all around movement..

 

[mcmxi]

As I was reading your first post I was thinking why don't you use a pintle hitch.
That hitch will let it articulate in every direction needed and it's STRONG!

Harbor freight has a killer price on a drop leg jack.

Thanks! I'll look at Harbor Freight for a jack. I like etrailer.com for stuff like this and have been looking at pintle hooks and lunette rings. The more I think about it, the more I like the pintle idea.

 

[MOOTS]

This is one of our implements at work. I’d be willing to bet there is a large bolt with nut on the other side of that round tube that is welded inside the square.

Your idea may be simpler to make with metal on hand.

 

[mcmxi]

View attachment 122028
View attachment 122029
This is one of our implements at work. I’d be willing to bet there is a large bolt with nut on the other side of that round tube that is welded inside the square.

Your idea may be simpler to make with metal on hand.

That's awesome! Thanks for posting those photos. I've never seen that set up but it was Option 3 minus a link so I don't see how that articulates in the vertical plane though.

I'm still leaning towards adding a jack and lunette ring to the harrow, and making up an adapter to pin a pintle hook onto the drawbar. Probably best to have the lunette ring adjustable for height so something like this.

 

[mcmxi]

As I was reading your first post I was thinking why don't you use a pintle hitch.
That hitch will let it articulate in every direction needed and it's STRONG!

Harbor freight has a killer price on a drop leg jack.

Something like this should be more than good enough for an old disc harrow.

3500 lb. Capacity Pipe-Weld Drop Leg Trailer Jack

Amazing deals on this 3500Lb Pipe-Weld Drop Leg Trailer Jack at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

 

[North Idaho Wolfman]

Something like this should be more than good enough for an old disc harrow.

3500 lb. Capacity Pipe-Weld Drop Leg Trailer Jack

Amazing deals on this 3500Lb Pipe-Weld Drop Leg Trailer Jack at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

That was the exact one I thought of!

 

[mcmxi]

This system for towing trailers off-road is cool.

https://www.etrailer.com/Adjustable-Trailer-Coupler/Lock-N-Roll/336TS502.html

https://videos.etrailer.com/static/images/video/Demo-Lock-N-Roll-Adjustable-Trailer-Coupler-336TS502.webm

 

[MOOTS]

That's awesome! Thanks for posting those photos. I've never seen that set up but it was Option 3 minus a link so I don't see how that articulates in the vertical plane though.

I'm still leaning towards adding a jack and lunette ring to the harrow, and making up an adapter to pin a pintle hook onto the drawbar. Probably best to have the lunette ring adjustable for height so something like this.

View attachment 122031

You’re right. Wasn’t even thinking of vertical, only left and right! I think your pintle idea is best.

 

[Trapper Bob]

I’m big on the “KISS” method. Seems to me a simple 2 5/16” ball hitch/coupler would work. It would be the same as pulling any trailer over rough ground. If there is not enough movement with the ball, the field needs to be leveled before disking.

 

[airbiscuit]

If you currently have a problem, it's a very small one. Isn't everything functional?

 

[Yooper]

Following this thread. I really like the direction you are going!

 

[mcmxi]

You’re right. Wasn’t even thinking of vertical, only left and right! I think your pintle idea is best.

I measured the lunette ring I have and the I.D. is 3". Those things are expensive so that's one less piece of the puzzle I'd need to buy.

I also took a closer look at the harrow and realized why the tongue height is controlled by a jack. There's a lot going on with this harrow. The front and rear discs are a fair distance apart, so a standard jack would be lifting the front discs off the ground to raise a fixed tongue. There's no suspension or air filled tires to accommodate gross movement of the tongue. Not sure if that makes sense.

I took some more measurements including the drawbar position relative to the ground on the M6060, the height of the tongue relative to the ground when the harrow is down and level, the bolt spacing of the lunette ring etc. This is not an urgent project, just something that I've started to think about and no doubt I'll have a better understanding of the way forward at some point.

 

[mcmxi]

If you currently have a problem, it's a very small one. Isn't everything functional?

I can pull the harrow around, but the slop on the clevis coupler makes for an unpleasant experience, and my property is hilly with lots of off-camber situations where the disc wants to go one way and the tractor another.

 

[mcmxi]

I’m big on the “KISS” method. Seems to me a simple 2 5/16” ball hitch/coupler would work. It would be the same as pulling any trailer over rough ground. If there is not enough movement with the ball, the field needs to be leveled before disking.

I just don't know how robust a ball and coupler interface is when pulling on rough terrain. The fact that pintle hooks and lunette rings are common for off-road applications, and the fact that there are off-road towing setups, it gives me the impression that a ball and coupler approach is less than ideal.

 

[Trapper Bob]

I just don't know how robust a ball and coupler interface is when pulling on rough terrain. The fact that pintle hooks and lunette rings are common for off-road applications, and the fact that there are off-road towing setups, it gives me the impression that a ball and coupler approach is less than ideal.

On the flip side, this is why I follow your threads. I’m guessing you don’t have to repair anything you have made. Do it right, do it once, move on to the next job (I’m big on that too).
Standing by …….

 

[mcmxi]

I’m guessing you don’t have to repair anything you have made. Do it right, do it once, move on to the next job (I’m big on that too).
Standing by …….

I despise rework with a passion. I try to do it right the first time and I never assume that the way something has been done for decades is the only or best way to do it. So much that we interact with is built to the "good enough" philosophy, had remarkably little thought put into it or was designed/made with profit margins running the show.

I'm not saying that this is the case with the disc harrow, but when I look at the wear on various parts, there could be a better mousetrap .... maybe. The clevis system is cheap and simple to make and is good enough for many farmers pulling discs over flat fields, but not ideal for those of us running discs over hilly, undulating properties. If I'm going to fix the sloppy clevis it makes sense to consider better design ideas for my use.

My friend on the river wants me to prepare a large area of his fields for a pumpkin patch this fall. His place is just about perfect for plowing and discing since he has rock-free soil and flat fields. I could run the disc as it is at his place but I want to do a lot of discing at my place this year.