Raytheon HSB L755, Owner'S Handbook Manual

Page: 47 / 224

Chapter 2: Installation 2-17
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2.6 Installing the Thru-hull Transducer
Tools and Material Needed
Water-based antifouling paint (mandatory for boats kept in salt water)
Safety goggles
Dust mask
Electric drill
Drill bit: 1/8" (3 mm)
Hole saw: Fiberglass or wood
2" (51 mm)
Aluminium or steel hull 2 1/8" (54 mm)
Sandpaper
File (for installation in a metal hull)
Mild household detergent or weak solvent (alcohol)
Marine sealant
Slip-joint pliers
Silicone grease or petroleum jelly
Tie-wraps
Cored fiberglass hull installation:
Hole saw for hull interior 2 3/8" (60 mm)
Cylinder, wax, tape and casting epoxy
Fairing (optional)
Level and protractor (installation with a fairing)
Band saw or hand saw (installation with a fairing)
Rasp (installation with a fairing)
Preparation
Fairing
Most vessels have a deadrise angle at the transducer’s mounting location. If
the transducer is mounted directly to the hull, the sound beam will be tilted off-
vertical at the same angle as the deadrise. A fairing is strongly recommended
if the deadrise angle at the mounting location is greater than 10° (see
Figure 2-12).
Figure 2-12: Deadrise Angle and Fairing Thickness
Transducer
Slope of hull
Deadrise angle
Parallel to waterline
Fairing
Backing block
Fairing thickness
at narrowest point
1/4 -- 1/2"(6 -- 12 mm)
Hull
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