INSTALLING THE STAINLESS STEEL WIRE CORD.
The object of this cord is to rotate the Recoil Drum as the boom is telescoped, thus measuring the length of boom
extended at all times.
The most suitable path for this cord is along the outside side of the boom anchored, at its free end, to the extreme end of
the final telescoping section, Not to the manual section. The anchorage should be of the spring, shock absorber type to
reduce the snatch on the cable when telescoping commences. Another anchorage may be needed (Point section
extended and jib cams are cut for angle ratings. When these cams are used, boom extension wire must be fastened at a
point 3 foot back of the normal position. This will bring the wire to the base section of boom and reel will not extend with
the boom. Ratings are then proportioned to angle.)
Suitable cleats should be provided along the boom to provide adequate guiding and protection of the cord.
At the root section, adjacent to the boom hinge, one or two deflector pulleys may be required to direct the cord to the
Recoil Drum. These pulleys should be as free running as possible, preferably on needle roller bearings. Careful
positioning of the deflector pulley, or pulleys, will reduce the error caused during booming to negligible limits although, it will
be found that the optimum position for the pulley is, as near as possible, directly on the center of the boom hinge pin.
It is also important to ensure that the cord does not come out of the groove of the pulley when the boom is fully derricked
in. Moving the Recoil Drum forward will improve this condition but, if necessary, the cord may be passed once round the
pulley to keep it in engagement.
The deflector pulley should be far enough away from the Recoil Drum to allow the cord to coil correctly on the drum without
"bunching". Introducing shins under the Drum mounting to tilt the assembly will assist the coiling should difficulty be met.
TO SET THE DRUM TENSION AND BOOM CORD.
1. Before assembling the Boom Cord to the Recoil Drum, rotate the drum periphery until it is fully wound up
(spring solid). Apply a suitable sprag.
2. Fully extend the boom. The manual extension may be in or out. (Outriggers should be out).
3. Attach the Boom Cord to the periphery of the Recoil Drum, passing the end through the hole in the periphery
and securing it with a solderless nipple within the periphery. Two holes are provided to suit the direction of the rotation of