Since its launch to the Irish market last summer, the Rubin 12 disc harrow from Lemken has worked its way around the country at various demonstration days and open nights. Lemken Ireland sales manager Diarmuid Claridge, says this machine is catching people's attention because it is expanding farmer perceptions of what a compact disc harrow was traditionally seen as being capable of.
"The Rubin 12 is suitable both for stubble cultivation and for primary soil tillage, even under the heaviest soil conditions," said Mr Claridge. "This machine allows for larger amounts of organic matter to be intensively and evenly incorporated into the soil. It is available either as a mounted rigid version with working widths of 3-4 metres, or as a hydraulic folding implement in semi-mounted versions with 4-6 metres working width."
During demonstrations in Ireland over the past few months, the Rubin 12 has been used for both grass reseeding and stubble cultivation. Lemken maintains that some farmers prefer to use a disc harrow for reseeding because it's faster, less fuel and labour intensive (no stone picking) and leaves the field smooth and level.
In tough lay ground that hasn't been ploughed or cultivated for years, Mr Claridge said the Rubin 12's weight and aggression can still make a field ready for sowing in two or three passes. "Recently we demonstrated the machine for a customer in a field that had been previously used as a tree nursery, so when the trees were dug out using a track machine you can imagine it was quite a challenge. However, with three passes of the Rubin the field was ready for sowing."
With two rows of large serrated concave discs with a diameter of 736mm, and a working depth of 20cm (8in), the Rubin 12 is a sharp looking piece of kit.
It works just as deep as a tined cultivator but it mixes and crumbles more intensively as part of the process. Lemken claims that the symmetrical arrangement of the discs in each row enables working without lateral pull, even at high driving speeds.
"Features such as the combined large disc footprint, the 20 degree angle of the discs to the soil and the inclined position to the direction of travel all lead to good soil penetration which enables cultivation over the whole width from a working depth of 7cm, or 2in. The legs on this machine are specially curved and coiled so they ensure a good amount of clearance between the discs; this prevents clogging, along with the slight offset of the middle discs," he explained.
Because of the higher forward speeds a driver can do with lower wheel slippage compared to when using a tined cultivator, the Rubin 12 is also capable of providing higher acreage performance with lower fuel consumption.
An impact harrow behind the first row of discs provides intensive mixing and crumbling, while a levelling harrow behind the second row ensures good soil distribution and perfect levelling. Both harrows have a central depth adjustment with a self-locking mechanism so that no locking device is required.
In the mounted version pictured, the Rubin 12 can be equipped with a depth and transport wheel.
This loads the front tractor axle when the implement is lifted, thereby making the machine stable during road transport and easy to manoeuvre at the headlands. In the picture a new semi-mounted system is used that lifts the implement without an additional control unit solely through activation of the three-point linkage, and transfers the weight of the roller onto the depth and transport wheel. In this way there are no more obstacles for using a big heavy roller to achieve better reconsolidation on mounted machines.
Like the smaller Rubin 9, the Rubin 12 also has individually mounted legs or discs that are sprung using a coil spring to give maximum tripping distance when travelling over stones and rocks.
This allows the machine to cope with tricky areas that might not have been used as tillage land before. More importantly, if one disc rides over a stone this doesn't affect the other discs and so they remain at work in the soil.
A maintenance free bearing hub is mounted at the rear of the disc ensuring clod free working is sustained even in sticky conditions.
A variety of rollers are available for the Rubin 12, ranging from cage crumbler rollers that leave the ground slightly tight, right up to profile packer rollers that leave the ground well tightened and reconsolidated.
The Rubin 12 retails at €21,000 plus VAT. For readers who are interested in seeing this machine in action, it will be on demo again during summer and autumn months. Anyone interested in getting a demonstration should contact their local Lemken dealer or Diarmuid Claridge on 086 0286844.