Samurai’s secret is built into the geometry

Adjustable blade angle gives operators big soil movement, while aggressive discs cut hard soils and stubble

To understand how the new Samurai disc blade functions in soil is a study in basic geometry. Summers engineers derived the precise subtle concave through miles of repetitive soil testing.

The new Supercoulter Samurai tillage tool is aimed at farmers who want the benefits of true vertical tillage, but want to move more dirt than the original Supercoulter.

Samurai can be used for residue management in spring or fall, in wet or dry conditions, in light tillage and seedbed preparation.

“We find that many of today’s farmers like the concept of true vertical tillage, but field conditions and personal preferences sometimes require something more aggressive, due to ruts, heavy residue, soil types or other factors,” said Bruce Johnson, director of innovation at Summers.

“Our exclusive Osmundson Samurai disc blade offers the latest in blade technology. It’s the same design we use on the VRT Renegade. They are slightly concave with a sawtooth design that excels at sizing residue and moving soil. They’re heat treated for extended life,” Johnson said in a phone interview, adding that finding the exact geometry that meets the criteria is a complicated challenge.

“I spend a lot of time dealing with issues surrounding soil health. That’s convenient for me because my office is at the Technology Park here at North Dakota State University. They have a very strong soil science program. We stay in touch with what farmers want in tillage, but also what the researchers are doing.

“They’re doing testing. A lot of testing. So are we. When we released the VRT Renegade in 2018, we had already put in a number of years in testing that blade. Osmundson brought it to us. We wanted a blade (that) farmers could run at very slight angle or a very aggressive angle. We wanted one blade to perform in a whole variety of conditions, even close to true vertical tillage.”

He says the conventional coulter blade with no concave works in true vertical tillage. It’s a slicing tool. But when you start rolling, all it does is slice. It cannot turn the dirt. That’s why Johnson went looking for a tool with some degree of concavity. The Osmundson blade had concavity, fluting and a vicious sawtooth circumference to penetrate hard ground and chew up residue.

“We tried quite a few different blade designs in our testing. There was a lot of trial and error. We found we didn’t need to change their design at all. We do a lot of testing with our long-time customers. We’ll give them some blades and they’ll use them. And you just can’t get better testing than that.

“We had a lot of guys telling us they liked what the Supercoulter does, but they wanted to move more dirt. So we ran the blade at angles from zero degrees to five degrees and we saw it can do whatever the farmer wants, within that range of zero degrees to five degrees. You get the amount of soil movement you adjust for.”

Johnson says blades are spaced 10 inches apart on each gang with the front and rear gangs offset for an effective five-inch spacing. The front gang blades are positioned at a three-degree angle and the rear gang blades are positioned at a five -degree angle. Testing has shown this to be the optimum configuration for achieving a good field finish in most conditions and soil types. All gang angles can be manually adjusted in the shop from one to five degrees to accommodate different soil types, conditions and personal preferences.

The Samurai frame design is similar to the original Supercoulter. Similar to the Supercoulter, the simplistic design of Samurai has a light enough footprint to help producers get in the field earlier in wet spring conditions.

Other standard features include a patented hydraulic hitch, the Super-Flex C-Shank gang mounting system and accurate depth control offering zero to 5.5 inches of tillage depth.

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