Disc Harrow different blade size and # of blades?

[Mitigator33]

I ran a search and did not find exactly what I was needing. I apologize if this has already been asked and answered.

I was looking at getting a Brown Manufacturing disc harrow and there are many models. What difference is there with the # of blades and their diameter. My thoughts were the larger the disc blade the deeper the cut but I am not sure on the amount of blades.

As an example there is a model that is 7'6 wide with 20 blades that are 20" in diameter or 20 blades at 22"in diameter and another the same width that is 22 blades at 20" or 22" and another with 24 blades at 20" or 24 blades with 22".

Each is a different price but I'm not sure what the advantages and disadvantages are. Any help would be appreciated.

Thanks,

Scott

 

[JoeinTX]

You are correct with regards to the diameter of the disc relating primarily to the desired depth you wish to cut.

The number of discs per axle relates more to the degree that you desire to condition the soil per given pass. More discs on an axle will ideally result in a more pulverized plowed soil with fewer clods, more chopping of plant material, etc. Fewer discs per axle will generally result in less conditioning but a deeper cut due to higher ground pressure per disc.

Generally (but not always) a deep plowing disc will have fewer discs of a larger diameter per axle while a harrowing disc will have more discs per axle and disc diameters may vary.

Disc size and number will depend on what you want the plow to do per the above. Weight also plays a large factor. For example, if you are moldboard plowing your ground and you want something follow behind and bust clods and smooth ridges then you'd probably go for a disc plow with more discs per axle to better process the rough plowed soil. On the other hand, if you're going to use the disc as your primary tillage tool, then you might probably want to go with something that will penetrate ground better and that would be one with fewer discs per axle.