ADJUSTING Three Point Hitch Mounted TANDEM DISC HARROWS

[BAP]

I hope that isn’t a finished harrowing job, because around here we would consider that a poor job. A good job shouldn’t any ridges or any valleys.

 

[jeff9366]

I hope that isn’t a finished harrowing job, because around here we would consider that a poor job. A good job shouldn’t any ridges or any valleys.

No, it is not. Just an illustration of how wide front gangs toss soil when Disc Harrow is pulled at a brisk pace.

 

[jeff9366]

Bought a Woods 5' Disc for the L3800
Purpose was to clean up some bottom land.
Only wants to go in 6 to 8 inches... thinking I need to add some weight for better performance?
Never been around or used a Disc... it does seem a little light compared to some I have seen.
There are several adjustments to angle... have it set in the middle.

The Woods Disc Harrow model number would be useful.


First, shorten your Top Link, that will shift more weight from the rear, smoothing gangs to the front, cutting gangs. Start with 60% front, 40% rear. [You can shorten Top Link until rear gangs are near clear of the soil.]

Second, increase the angle of attack for your front gangs. With increased angle of attack, increased cutting will occur; unfortunately draft force resistance also increases.

Generally speaking you want front gangs set to give the degree of cut/penetration desired.

The rear gangs should be set less aggressively than the front gangs; just aggressively enough to provide smooth bed behind the implement.

How aggressive the front gangs are set determines input to rear, smoothing gangs.

A Disc Harrow with 9" spacing between pans will cut significantly more aggressively than a Disc Harrow with 7" spacing. A Disc Harrow with 7" spacing between pans will leave a significantly smoother bed behind the implement.

A Disc Harrow with 18" diameter pans can penetrate only around 6" deep in best conditions before pan hubs limit penetration.

If you have "outrigger" furrows trailing from the outer pans, rear gang, raise the entire Disc Harrow one inch with your hydraulic Position Control lever then tweak the Top Link if necessary.

I regularly view ridiculous photos of weighted Disc Harrows. If you cannot achieve penetration desired through gang angle adjustment you need a Tandem Disc Harrow with larger diameter pans or, if you have a light tractor, a PTO-powered roto-tiller.

 

[jeff9366]

Going to be broadcasting 1.5 tons of mixed seeds: cowpeas, pigeon peas, canavalia, moringa and castor bean.
The large plot, which is currently cow pasture will be prepared with subsoiler, 5 bottom plow, and disc harrow.

Would a second pass with the disc harrow be good enough to plant (partially bury) these mostly bean-sized seeds? Or would they maybe go too deep?

If you adjust the gang angles on your Disc Harrow to relatively minor angles, the DH will bury seeds less deep.

If you adjust your Top Link so 40% of the weight is on the front gangs, which throw dirt out and will leave seed on the surface, and 60% of weight on the rear gangs, which gather dirt in, covering the seeds, you should be good with bean size seeds, assuming you subsequently have 3/4" or more rain per week.
(Rear gang is wider than front gang.) (Longer Top Link transfers more DH weight to the rear gang.)

In addition, use the Three Point Hitch hydraulic position control to just set the DH pans just into the soil surface.



Smaller seeds often require sunlight to germinate. Covered, small seed germination declines. Small seeds are best pressed into the surface of the soil, uncovered, with a Cultipacker. PHOTOS

MORE: https://www.tractorbynet.com/forums...ing-three-point-hitch-mounted.html?highlight=

 

[jeff9366]

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CREDIT: - pmbutter - March 18, 2019

"There is a lot of contradictory information about choosing optimal paired holes to pin tractor/inboard end of the top link to the tractor.

The top hole gives the least elevation change of the tail wheel, but better maintains parallelism with the ground.

An earth turning plow ought to be in one of the upper holes, so it remains at a proper working angle, regardless of its depth.

The bottom hole provides the greatest elevation change of the "tail wheel" of my "implement", but it also the greatest angular change relative to the plane of the ground.

The bottom hole is best for something like a landscape rake where you might want to lift it up and out of the way, perhaps with a little more angle so trash drops off the tines."



RELEVENT VIDEO:

I will experiment with connecting the inboard pin of the Top Link to each of the four paired, vertically stacked mounting holes on my L3560.

For Disc Harrow smoothing it would seem the top holes might even harrow pressure of all pans in contact with the soil.

For Disc Harrow cutting/penetration it may be connection at the bottom holes, combined with a shortened Top Link, will shift weight to the forward cutting pans in an interesting way.

I have to experiment......

 

[jeff9366]

Creating raised garden beds with a Disc Harrow:

LD1 - 7/24/2022​

Do you have a 3PH disc? A 6 or 7' disc?

We use a disc to create garden beds for sweet potatoes.

1) The front disc gangs/pans throw dirt outward.

2) With a level disc you get a level field.

3) The rear gangs pull dirt toward the middle of the disc.

Set the rear disc gangs/pans as aggressive as you can. Lengthen the toplink all the way to let the rear gang dig in and keep the front gang out of the dirt.

With the front gangs kept out of the dirt and the rear ones pulling dirt in, you get hills/rows.

I use the same gathering-in adjustment to fill the dead furrow after moldboard-plowing the field.