Should you happen to have 1,000hp or so burbling away in your forage harvester, then you would naturally wish for the swath to be big enough to justify having that power available to deal with it quickly and efficiently.

The haybob is out of its league, single, and even twin-rotor rakes are hardly up to the task, so the job calls for something bigger still, in fact, big enough to draw in grass across 40ft of ground.

Four rotors, and a 14m reach

Enter the four-rotor rake – machines capable of satisfying the appetite of the largest of harvesters and rowing up fields in minutes rather than hours.

14m rake Fermoy farm — Effortless raking with 230hp to hand, although it’s as much about tractor mass to handle a large machine as it is available power

Pottinger’s latest contribution to this steadily increasing sector of the rake business is the Top 1403 C, which has an adjustable working width of 8m to 14m.

Introduced in 2021, a demo model is now out and about, showing off its capabilities to in Co. Cork where Agriland caught up with it on the farm of Mike Dunne in Fermoy.

Click the video below to see the rake in action.

A long way to move grass

14m is a big stretch and a lot of metal is required to deal with the forces involved in bringing enough grass together for a large harvester. The Pottinger rake appears not to be left wanting in this regard.

Pottinger Top 1403 grass rake Harvester swath — When folded, the amount of engineering and metal within the machine becomes even more evident

Altering the working width can be done in two basic ways, the first is to have the rotor arms moving in and out telescopically, while the second is to fold them hydraulically.

And it is this second method that Pottinger has chosen for the front rotors while the rear remain as telescopic units.

Folding front arm adjusts width — The front arms fold in or out to adjust working width

Telescopic arms allow power to the rotors to be provided by PTO-type shafts, whereas folding arms will require hydraulic drive to the rotor head.

Flexible drive line

Pottinger uses oil to power the front rotors but as the rear arms are telescopic, they can still be shaft driven, so the reservoir and pump is fitted towards the front end of the frame.

oil driveline shaft Harvester — Hydraulic motors mounted on the rotor head drive the front tines

Having all arms independently adjustable while on the move allows for an overlap control system to be used.

Pottinger top grass rake arms Harvester — The arms can be set to automatically withdraw at field corners

Using a sensor on the headstock, the degree of turn can be monitored and the arms moved in or out to reduce overlap when turning the corners when working on the headlands.

The lateral movement of the rear rotors allows the swath width to be adjusted from 1.4m to 2.3m on the move.

Drive shafts to rotor Harvester — The rear rotors are of the telescopic type and are driven by shaft rather than oil

Other major adjustments include rotor height and ground wheel pressure, both of which can be adjusted remotely from the cab, via the tractors ISOBUS screen or Pottinger’s own control units.

Tracking the ground

There are five wheels supporting each rotor on this model plus an adjustable jockey wheel mounted outside and in front of the rotor, by which a more constant working height is maintained.

Multitast jockey wheel maintains rotor height at pre-set level — Multitast jockey wheel maintains rotor height at preset level

Pottinger calls this option the Multitast wheel. It can be adjusted from within the cab to suit variables such as stubble length and other ground conditions.

In-cab controls

The rake is fully ISOBUS compatible, allowing its functions to be controlled remotely and the settings to be adjusted on the go, with the position of the various components being shown on the screen.

Once the machine has been adjusted to suit certain conditions the various positions may be programmed in future use. Up to three different combinations of settings may be recorded this way.

Screen ISOBUS control unit — The rake control unit is on the right, the other two being that for a set of Pottinger mowers and the tractors own control screen

At the time of visiting, the section control was not engaged but when it is, the rotors will automatically lift independently of one another as it approaches the headlands.

Even without GPS, a delay can be set between the front and rear units lifting out of work to protect the rows on the headland.

Feeding the harvester

The rake will automatically fold upwards for transport with each rotor arm being locked securely in place. Transport height is 4m while transport width is 3m. Minimum power requirement is 120hp.

Transport lock rotors Harvester — It is less than 4m high in transport without the need to remove tine arms

Overall it is a formidable machine that reduced the matter of rowing up fields suitable for a 1,000hp harvester to minutes, and that was with an operator who was new to it.

Mike Dunne was certainly impressed, although he did note that there would probably be small areas of fields that would be left uncut due to the extra width.

Pottinger grass rake areas — With increasing width comes the problem of fitting into tight corners, or around obstructions

It was also thought that it would further increase the reliance of the harvester driver upon the rake-man to produce a pattern of rows that could be efficiently picked up, effectively making it much more of a contractors tool, but one that would work well when firmly embedded in a harvesting operation.

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Video: Pottinger 4-rotor rake in Co. Cork keeps the harvester happy