Hardi COMMANDER TWIN FORCE Series, Instruction Book

Page: 41 / 110

4 - Sprayer setup
4.11
ATTENTION! Fine tuning of air speed and angling will often be necessary all through the spraying job.
ATTENTION! It is easiest to find the best air setting to reduce drift when the sun is low and behind the boom (bac-
klight). These conditions make the drift more visible.
The air speed and angling must always be adjusted individually for each spray job and the given weather conditions. It is
always a good idea to get used to a new sprayer out in a field with only water in the tank, on this occasion the following
routine for air adjustment should be practised:
1. Start with the air vertical
2. Set the air speed: See section “Setting of air speed, rules of thumb”
3. Find the best angling: See section “Angling of air and liquid, rules of thumb”
4. Readjust the air: See section “Setting of air speed, rules of thumb”
Step 1: Find the range of air speeds that can control drift
1.Start with the air setting at zero and keep increasing the air speed just to the point where you can see that the drift
cloud is minimised - note minimum setting.
2.Then increase the air speed until you see drift again - note maximum setting.
3.Now you know the range of air speeds that can be used with minimum drift.
Bare ground / low crop: The range of air speeds is usually very small.
Taller crop: The taller the crop the wider the range of air speeds that can reduce drift.
At higher wind speeds: More air is needed on the sprayer and it is advisable to drive more slowly and use minimum
boom height (40 cm)/(16 in).
Too high air speed over bare ground/low crop can cause reflection of the spray liquid and leave dust on the leaves,
which can again reduce the effect of the plant protection product.
Step 2: Set the optimal air speed within possible the range mentions above.
Air speed recommendations:
Bare ground / low crop: Use maximum air within the possible range.
Taller crop: Deeper crop penetration requires more air on the sprayer (if you are in doubt check with water sensitive
paper).
Forward speed: Higher forward speeds require more air on the sprayer.
Volume rate: Lower volume rates require more air assistance to prevent drift.
Setting of air speed, rules of thumb
Adjusting the air assistance
TWIN Air technique