• Design allows the option to fit tyne opener
  • Can be mounted to either square or diamond beams
  • Single or double shoot option
  • Available with either plain or scalloped (or a combination of both) opening coulters

Maximize seed germination with Double Disc Openers

Benefits of a double disc opener include more uniform seeding depth, reduction in draft forces, trash handling ability, reduced soil disturbance and faster sowing speeds. In some cases disc openers are more suitable than tynes when sowing into rocky conditions.

Sowing with a double disc opener leaves a smoother soil profile and will assist in reducing water run-off.

Unique Design

The John Shearer opener is well built to perform in many different soil types and conditions. Its compact and unique design means that the press wheel is much closer to the sowing boot than most others on the market.

The opener is a true parallelogram unit based around two carriers: (1) the mounting carrier which attaches the unit to either a square or diamond mounting frame and (2) the main carrier on which the ground engaging coulters, (or optional tyne) and press wheel are attached.

Press Wheel

The trailing press wheel provides depth control as well as cover and compaction of the soil around the seed to assist with germination.

Easy Adjustment

An easy to use ‘spring pin’ to lock the press wheel arm into place is used to control the depth and provides
6mm increments over a 50mm travel. The spring loaded opener has a mechanical screw assembly to easily adjust the main spring to decrease or increase pressure of both the opening coulters and the press wheel. Downward force can be increased to help cut through stubble residue and in drier conditions penetrate the soil for good seed placement.

The spring breakout pressure can be adjusted up to 182kg (400lb) and the unit has 254mm (10”) of vertical ground following capability.

Low Maintenance

Hardened pins are fitted in all high load areas to extend operational life.


Actuation Spring
Ground engaging Double disc or tyne option
Coulters Scalloped or plain
Sowing boots Single or double


Coulters 380mm (15”) high carbon steel
Press wheel 380mm (15”)
Hubs, 6 hole Triple lipped sealed bearings
Pressure adjustment Mechanical screw
Vertical travel 254mm (10”)
Overall length 900mm press wheel to coulter
Packing force 182kg (400 lb)
Underframe 620mm from mounting beam

Due to our policy of continuing research, specifications are subject to change without prior notice.