Precision tynes are tynes that have their depth controlled independently from the frame that they are carried on. They fall into two broad types; Parallelogram tynes and Presswheel depth controlled tynes.
Parallelogram Tynes were invented in the summer cropping ares of Australia. They were designed to no-till summer crops while maintaining accurate depth control.
The tynes listed below have these features in common:
a) Leading gauge wheel and coulter controls depth of tyne
b) Tyne places seed
c) Independant trailing springloaded presswheel firms seed.
The Rogro Zero-Till Master Row Unit, Excel Stubble Warrior CR 600, Boss Ag TX Tyne and Janke Parallelogram Tyne use separate springs for coulter down force and tyne breakout.
The Gason Para-maxx is the same as above except it uses two hydraulic rams, one for the coulter and one for the tyne.
The Gessner Parallelogram Tyne uses a single hydraulic ram for coulter down force and tyne breakout. The position of the ram is adjustable allowing independant force for the two operations.
The Simplicity Striker appears to use a single hydraulic ram for all three functions. From the pictures it is unclear if there is independant pressure for each function.
Simplicity Striker
Twin disc option Simplicity, Gason and Rogro offer the option of a twin disc and vee presswheels to replace the tyne and single presswheel. This allows the option to use a tyne or disc seeder as the need arises.
Presswheel Depth Controlled Tynes were invented in Canada to no-till spring crops while maintaining accurate depth control. These units are not as accurate as the parallelogram tynes above but as they are cheaper they are well suited to the narrower row spacings for planting winter crops.
The following have a long trailing arm with two tines, one for fertiliser and one for seed, and a presswheel. The presswheel controls the depth of the seed tyne which is positioned behind and beside the fertiliser tyne. All Canadian designs.
Seedmaster
Seedhawk
John Deere Conservapak
These have the parallelogram behind the main tyne with a separate tyne and presswheel mounted on the parallelogram. All Australian designed.
Ausplow DBS
Horwood Bagshaw
Gason HydraTILL
The following have a single tyne mounted on a parallelogram with depth controlled by a presswheel.
Multiplanter (Aus)
Morris Contour (Can)
