Disc harrow disc size question

   / Disc harrow disc size question #1  

RancherSam

Silver Member
Joined
Aug 8, 2005
Messages
102
Location
Hays County, TX
Tractor
Case IH JX95 4x4
I bought a used 14' disc harrow a few months back, I think it's a rhino. It takes 18" 1 1/4 hole discs. It currently has smooths on the front gangs and notched on the back. Some of the discs are fairly worn down and some are ok. I took it out in the field, and being that I have a fair amount of rock, didn't get very good results. The discs just rode up on top of the rocks, some went into the ground and some were barely touching the soil. Looks like I'm going to need to add more weight to it as well. So, I'm looking at modifying it. I have a couple of 20s on the front gangs because that's all that the local dealer had. I'm looking at replacing all the front discs with 20s, and keep 18s in the back ( is there anything wrong with this ? ). I'm also going to fill up a few buckets with concrete and load the disc down. I'd love to hear any voices of experience on whether I'm missing anything.
 
   / Disc harrow disc size question #2  
Hi Sam; wow, good thing you have a Case JX95 pulling machine; a 14' disc can be a HUGE load to pull.

Your plan to replace the disks, and your intended sizes sounds fine to me. My only comment is re: your rocky ground. Try breaking up the rocky areas with rippers first. Like a large box blade with scarifiers, or an old plow, or something that can rip it up. Then the disc will do a great job. It's not always a matter of loading on tons of weight, it's the soil consistency. For example, if your disc is adjusted to really bite, and you are in sandy ground, it will dig in SO much, you likely couldn't even pull it. In your case, it sounds like if you break the ground up first, your disc will then cut a good 6" deep. Then go over it a 2nd time, from a 90 degree direction, and that will mix up the ground real well......
 
   / Disc harrow disc size question #3  
A 14' disk us usually plenty heavy. I assume it has tires and you can adjust the depth of cut by keeping the tires partly on the ground... this is good. For rocky ground, I suggest scolloped disk blades... they always worked better for me than smooth blades. Yep, working the ground with a chisel plow first is recommended. For some reason, it always seems to me that the front blades dig in deeper than the back blades. So, if I were going to go with different size blades, I'd put the larger ones on the rear. And as bill6 says, try different angles of attack for the gangs of disks.... max angle will really challenge your tractor. Then, failing all else, add weight, but that would be my last option.
 
   / Disc harrow disc size question #4  
RancherSam said:
I bought a used 14' disc harrow a few months back, I think it's a rhino. It takes 18" 1 1/4 hole discs. It currently has smooths on the front gangs and notched on the back. Some of the discs are fairly worn down and some are ok. I took it out in the field, and being that I have a fair amount of rock, didn't get very good results. The discs just rode up on top of the rocks, some went into the ground and some were barely touching the soil. Looks like I'm going to need to add more weight to it as well. So, I'm looking at modifying it. I have a couple of 20s on the front gangs because that's all that the local dealer had. I'm looking at replacing all the front discs with 20s, and keep 18s in the back ( is there anything wrong with this ? ). I'm also going to fill up a few buckets with concrete and load the disc down. I'd love to hear any voices of experience on whether I'm missing anything.

My neighbor has been renovating 30 acres of hayfield (three 10-acre plots) for the past 3 months. The ground is not particulary rocky, but it is pretty compacted.

He used a single shank parabolic ripper (aka sub-soiler) to break up the hardpan to about 24" depth. Used a Massey Ferguson 294 (75 hp engine) and it took all those horses to pull that ripper. He ripped on 30" centers along both diagonals to the fence lines.

Then he used a 10-ft wide tandem disc parallel to the fence lines to break up the clods. He spent a lot of time going over the ripped area to get it tilled the way he wanted it.

Since he plans to use surface irrigation to grow alfalfa, he laser-leveled the fields using his D7 cat pulling a 10-ft wide laser-controlled scraper. He seeded using the 294 and a grain drill. Finally he used a two-disc hiller to build the checks that define the irrigation channels.
 
 
 
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