Installing navigational electronics on an inflatable vessel is a task that requires a different approach than fitting a rigid hull. PVC And the soft transom dictates their own installation conditions, where flexibility of the joints and protection from vibrations are critical, and improper fixation can lead not only to the loss of expensive equipment, but also to damage to cylinders when hitting underwater obstacles.
Modern. sonar And the cartplotters are more compact, but their sensors are still sensitive to mechanical stress, and the challenge is that the inflatable boat transom often has variable geometry and is prone to displacement under engine load, which is why choosing the method of attaching the emitter becomes a key stage in the preparation for the season, determining the quality of the image and the durability of the entire system.
In this guide, we will take a detailed look at all the steps of the process, from choosing the optimal installation site to the final sealing of the connections, you will learn about the nuances of working with a soft transom and get answers to questions that often arise from owners. floater.
Selection of installation site and preparation of transom
The first step is always to carefully mark the surface, and on the hard PVC transom of a boat, the installation area is not only limited by geometry, but also by the location of power elements such as the shingles and cans, and you need to find a site where the surface is as flat and vertical as possible when lowered into the water.
It is important to consider the direction of the boat's movement. The sensor must be mounted strictly in the center of the transom or with a displacement in the direction opposite to the rotation of the screw to avoid getting into the cavitation flow. blockmaking the readings of the device useless.
- 📍 Choose a place below the waterline with a margin of 10-15 cm to account for roll.
- 🔌 Make sure the cable freely reaches the head unit installation site without tension.
- 🚫 Avoid areas near drainage holes or valves.
Before installation work begins, the surface of the transom must be degreased. Use alcohol or specialized cleaners that do not contain aggressive solvents that can damage the structure of PVC. The purity of the surface ensures a reliable adhesion of the glue or sealant to the material.
⚠️ Warning: Never use acetone or gasoline to degrease PVC translatum – these substances can dissolve the top protective layer of tissue, which will lead to stratification and loss of strength at the attachment site.
Types of fastening: removable and stationary solutions
There are two basic approaches to fixing the emitter on an inflatable boat: temporary and permanent. Temporary mounting is often implemented through a slats or special suction cups, which is convenient for storing the boat in assembled form, but less reliable at high speeds.
The stationary method involves gluing the site or the sensor directly to the transom, which is the most reliable option, eliminating the risk of loss of the device, but it requires careful preparation and use of quality adhesives compatible with polyvinyl chloride.
When choosing a stationary method, an additional area of textolite or plastic is often used, which is already glued to the transom, which allows you to distribute the load and simplify the replacement of the sensor in the future without risking damage to the main material of the boat.
Installation tools and materials
A minimal but specific set of tools will be required to perform the work properly, and the main focus should be on the choice of sealant, as it will be responsible for the waterproofness of the unit under dynamic loads.
In addition to the standard set of screwdrivers and scissors, you will need special compounds. For PVC, two-component polyurethane adhesives or specialized sealants for inflatable boats that retain elasticity after drying are excellent.
☑️ Materials required
Don't forget to prepare a cable channel or corrugated cable to protect the wire. Although modern cables have strong insulation, additional protection against rubbing on the side or transom will never be superfluous, especially in inflatable conditions.
Step-by-step instructions for installing the sensor
The installation process starts with fitting, and you can put the sensor on the selected location, check the angle of inclination of the work surface, which should be parallel to the bottom, and any deviation from the vertical can distort the depth reading.
Apply the sealant to the mounting pad or directly to the sensor surface (if the design permits), the layer should be uniform, without voids, but also without excess that can be squeezed out. Carefully press the element against the transducer and lock it with a load or a strub until the initial grasp.
| Work phase | Action. | Drying time |
|---|---|---|
| Degreasing | Liquor-wiping | 5-10 minutes |
| Applying glue | Equal distribution of composition | Depends on the type of glue. |
| Fixation | Pressing and placing the load | 24 hours (full) |
Once the main element is installed, you need to organize the cable output, the wire should not have sharp inflections, optimally run it along the transom, fixing it with plastic clamps or gluing it with small strips of PVC fabric.
⚠️ Note: Do not use metal clamps or braces to fix the cable on the transom – they can rust and damage the insulation of the wire, which will short circuit and the electronics will fail.
Sealing connections and cable protection
The most vulnerable place of any system on the water is the cable entry into the sensor case or the connector. Even if the connector is marked IP67, constant contact with water and temperature changes can over time break the tightness.
For added protection, we recommend using adhesive-layer shrink tubes, and when heated, the adhesive inside the tube melts and fills all the voids, creating a monolithic connection, which is especially true for places where the cable connects to the emitter.
How to check the tightness of the connection?
So, you can put the joint in a water tank for 15 to 20 minutes, and if bubbles don't show up, you can have a tightness, and you can use a soap solution, you can put it on the joint, and you can watch for soap bubbles when you apply pressure (if you can build it).
The cable that goes from the transom to the control unit must be protected from ultraviolet light and mechanical damage, use a corrugated sleeve or spiral braid, which will prolong the life of the insulation, which becomes brittle in the sun.
Setup and testing of the system on water
The first run of the system is better done in shallow waters where the exact depth is known, so you can calibrate the device and make sure there is no signal failure, turn on the sonar and slowly lower the sensor into the water, watching for the appearance of the bottom echo.
Notice that you're operating at different speeds, and if you add gas, you start to make noise or you lose, you're going to get air in the sensor, and you're going to need to adjust the depth of the emitter.
- 🎣 Check the operation at different frequencies (200 kHz / 83 kHz).
- 🌊 Evaluate the signal stability in chop.
- 🔋 Make sure the battery connection is secure and there are no power surges.
If vertical interference bands appear on the screen, try to take the sonar power cable away from the outboard motor cable - this will help to avoid electromagnetic tips.
It is also important to check the reliability of the attachment after the first trip, the glue may not have gained full strength, or the vibration may have weakened the locks, and repeated stretching and inspection after a few hours of operation is a mandatory procedure.
Typical errors and ways to fix them
One of the most common mistakes is to set the sensor too high, and owners are afraid to damage it to the bottom, but as a result, they get constant signal loss due to aeration of water by the screw. The optimum depth of the installation is 30-40 cm below the bottom point of the transom when immersed.
Another problem is the use of the wrong adhesive. Silicone sealants that are not designed for PVC can just peel off after the season. Always check the compatibility of chemistry with the material of the boat.
⚠️ Warning: Do not install the sensor in the direct impact zone of the engine exhaust jet (if it is a two-stroke engine with underwater exhaust). Hot gases create powerful acoustic noises that completely drown out the echo signal.
If you notice that the cable is rubbed against the edge of the transom, immediately organize protection. Use rubber bushings or additional layers of wear-resistant fabric, ignoring this moment will lead to water entering the cable and corrosion of the contacts.
The key to success is the use of specialized PVC materials and adherence to degreasing technology before gluing, and the savings on sealants are unacceptable here.
Can I attach the sensor to the suction cup?
Suction mounting to the cylinder is only possible as a temporary solution for quiet water. At speed, the suction cup often breaks off due to the deformation of the cylinder, and the sensor itself can hit the screw. In addition, the soft surface of the balloon does not provide stable geometry for a clear signal.
Do I need to take off the sensor for the winter?
If the boat is stored in a warm room, the sensor can be kept in place, but it is advisable to close it from dust. If storage takes place in an unheated garage or on the street, it is better to dismantle the electronics, since the freezing-thawing cycles can disrupt the tightness of the adhesive seam and damage the emitter crystal.
How does the color of the transom affect the sounder?
The color of the PVC fabric does not affect the work of the sonar, as it uses sound waves, not light. However, the dark transom can be more heated in the sun, which should be considered when choosing the type of sealant - it must maintain elasticity at high temperatures.