Great Plains YP825AR Material Rate - Manual (Page 22)

18 YP825AR Table of Contents Metric Charts Great Plains Manufacturing, Inc.
401-923B Table of Contents Metric Charts 2013-11-11
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 page 19 and 55 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 14
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 14
40% Rear Timing Adjustments
29717
Example:
The front sprocket is “1”. At a target population of
31,500 seeds/ac, the rear sprocket is at tooth “17”.
At this population, spacing in a single row is:
13.3 inches
The rear row seeds would be ideally at:
6.6 inches
ahead or behind the front row seeds.
We find that the rear seeds are being placed:
1.5 inches behind the front seeds.
We need to move the rear seeds back another 5.1 in.
A 40% advance is 5.3 inches at this seed spacing.
Advance or Retard to adjust - see instructions in Seed Rate Manual.
These Columns are for Fine Adjustment Only
Population Initial Rear 20% Rear Seed Drop Adjust 40% Rear Seed Drop Adjust
Seeds/Acre Tooth Number Retard Advance Retard Advance
31000 9 10 6 4 3
31500 17 14 1 4 18
32000 17 14 2 11 18
32500 5 14 2 8 18
33000 5 18 5 8 14
33500 2 18 17 15 14
34000 1 18 17 12 14
34500 1 3 9 12 14
35000 6 3 9 19 10
35500 6 3 13 19 10
36000 10 7 13 16 10
36500 10 7 13 4 6
Example:
Moving the rear sprocket from tooth 17 to tooth 18
provides a 40% advance.