Material Rate User Manual

Great Plains Manufacturing, Inc. Table of Contents Sprocket Indexing (Stagger) 69
2014-03-17 Table of Contents 411-020B
Indexing Fine Adjustment
If, after indexing, the twin-row side-to-side seed stagger
is substantially imbalanced, it is possible to make small
adjustments that may correct it. Imbalance can occur
over time as row unit chains wear and stretch.
The Indexing charts on pages 73 and 75 provide
columns for alternate rear row sprocket alignments.
These settings move the placement of the rear seed
drop. The amount of movement is given as a percentage
(±20% or ±40%) of the in-row seed spacing.
Refer to Figure 16
Adjustments are made only to the rear row timing.
• Advancing the timing (dropping the seed sooner,
moves the seed position back).
• Retarding the timing moves the seed position forward.
If an adjustment is made, test it on one row pair before
adjusting the entire planter.
Indexing Adjustment Steps
1. Make sure the current front sprocket index is 1, and
the current rear sprocket index number matches the
“Initial” number in the indexing chart for the
population being planted.
2. Measure the actual stagger at the rear row seeds.
3. Determine by how many inches (or cm) the rear
seed placement needs to move in order to be
centered between the front seed placements.
4. Determine the percent of seed spacing, and whether
advance or retard, required to adjust the rear seed
drop to the desired spot.
5. In the tables (thumbnail view of one shown at right),
find the new rear sprocket tooth setting for the
percent retard or advance desired.
Figure 16
40% Rear Timing Adjustments
29717
Example: 70 cm Twin Row
The front sprocket is at “1”. At a target population of
90000 seeds/ha, the rear sprocket is at tooth “2”.
At this population, spacing in a single row is:
15.9 cm
The rear row seeds would be ideally at:
8 cm
ahead or behind the front row seeds.
We find that the rear seeds are being placed:
5 cm behind the front seeds.
We need to move the rear seeds back another 3 cm.
A 20% advance is 3.2 cm at this seed spacing.
These
Columns
are
for
Fine
Adjustment
Only
Population Seeds/Hectare
Initial Rear 20% Rear Seed Drop Adjust 40% Rear Seed Drop Adjust
70.0 cm 75.0 cm 76.2 cm 91.4 cm
Tooth Number Retard Advance Retard Advance
84732 79083 77838 64865 17 14 1 4 18
86077 80339 79073 65895 17 14 2 11 18
87422 81594 80309 66924 5 14 2 8 18
88767 82849 81544 67954 5 18 5 8 14
90112 84104 82780 68983 2 18 17 15 14
91457 85360 84015 70013 1 18 17 12 14
92802 86615 85251 71043 1 3 9 12 14
94147 87870 86487 72072 6 3 9 19 10
95492 89126 87722 73102 6 3 13 19 10
96837 90381 88958 74131 10 7 13 16 10
98182 91636 90193 75161 10 7 13 4 6
99527 92891 91429 76191 10 7946
100872 94147 92664 77220 14 11 17 4 1
102216 95402 93900 78250 14 11 17 8 2
103561 96657 95135 79279 14 11 5 8 2
104906 97913 96371 80309 18 11 2 8 5
106251 99168 97606 81339 18 15 2 12 17
107596 100423 98842 82368 18 15 1 12 17
108941 101679 100077 83398 3 15 1 12 9
110286 102934 101313 84427 3 19 6 16 9
111631 104189 102548 85457 3 19 6 16 13
112976 105444 103784 86487 7 19 10 16 13
114321 106700 105019 87516 7 4 10 16 13
115666 107955 106255 88546 7 4 10 16 9
117011 109210 107490 89575 11 4 14 16 17
118356 110466 108726 90605 11 8 14 16 17
119701 111721 109961 91635 11 8 14 16 5
121046 112976 111197 92664 15 8 18 16 2
122391 114231 112432 93694 15 12 18 16 2
36076L
Example:
Moving the rear sprocket from tooth 2 to tooth 17
provides a 20% advance.