Instructions
18
Place a spirit level on the middle of a boom wing.
The far end of the boom wing should be raised a little relative to the
horizontal position.
The bubble in the spirit level should just be touching black line as shown
here, then the adjustment is all right.
To adjust the boom wing up or down, turn the nuts holding the black
steel bar at the top.
Pull the black steel bar at the top towards the boom centre to raise the
boom wing or the opposite way to lower it.