Modern inflatable fishing is unthinkable without a sonar that allows you not only to find fish, but also to analyze the bottom relief. However, owners of PVC boats often face the problem of installing a sensor, since the rigid transom is designed for the engine, and the sides are too soft for standard mounts. Self-manufacture of the bracket solves several problems at once: reduces the cost of expensive factory analogues and allows you to adapt the design to a specific model of the boat.
The homemade holder gives the opportunity to position perfectly sonarAnd this is critical to getting a clear picture on the screen, and unlike the general-purpose store, your design will take into account the cylinders, the stringers and the height of the transom, and a well-designed mounting unit will not damage the sensitive PVC material and will withstand the loads when you move along the wave.
In this article, we will take a closer look at the process of building a robust bracket, from the choice of materials to the final installation, how to avoid common mistakes that lead to the loss of expensive equipment or damage to the boat, and how to do this will ensure that navigation electronics work smoothly for many seasons.
Choosing the optimal location for the sensor installation
Before you pick up tools, you need to decide on the type of attachment, because it depends on the hydrodynamics of the boat and the quality of the signal. For PVC boats, there are two main options: mounting on a transom (hard jumper) or on an inflatable side. The transom version is considered more stable, since it provides a rigid fixation of the emitter, but requires free space on the rear bar.
Fixing on board is often chosen by owners of boats with low transoms or when the seat is occupied by the suspension of the engine. balloonIt's important to understand that when you're onboard, the sensor can sail more and shift more when you're turning the boat abruptly.
Some anglers prefer to install the sensor inside the boat, gluing it to the bottom, but this method is only suitable for models with an inflatable floor of NDND and gives a significant loss of sensitivity. For classic boats with plywood piola, external installation remains the only solution to obtain a quality picture of the bottom. The choice of location also depends on the length of the cable that must reach the display without tension.
⚠️ Warning: When choosing a location, make sure that the sensor does not bubbly water from the engine propeller, otherwise you will get false depth readings or complete signal loss.
Determine the optimal angle of inclination of the sensor's working surface, which is usually 90 degrees to the water surface when moving. The wrong angle will cause the signal to reflect from the water surface rather than from the bottom, which will make using the sonar meaningless. Careful planning at this stage will save time for redesigning the structure in the future.
Required materials and tools for the work
To make a strong and durable bracket, you'll need to find materials that are resistant to aggressive aqueous environments and ultraviolet radiation. The base of the structure is most often made of aluminum profile or strip stainless steel, because these metals do not rust and are easily processed. Using conventional ferrous metal will lead to rapid corrosion and rusty flows on a white boat.
As fasteners, you should use only AISI 304 or AISI 316 stainless steel, as conventional fasteners will rust after the first season. To protect the contact of the metal with PVC, it is recommended to use rubber gaskets or Cambrians that will prevent mechanical damage to the cylinder, and you will need epoxy adhesive, sealant and possibly a piece of textolite for insulation.
The list of tools for work is quite standard and is found in the garage of most masters:
- 🔧 A drill or screwdriver with a set of drilled on metal
- ✂️ Metal knife or Bulgarian with a cutting disc
- 📏 Roulette, marker and coal for marking
- 🔨 Edge-handling files and fillers
- 🔩 Set of wrenches and screwdrivers
Special attention should be paid to insulation materials, as galvanic Aluminum and stainless steel in salt water can cause electrochemical corrosion. For freshwater, this is less critical, but using dielectric gaskets will never be superfluous. Quality materials will ensure the long life of your homemade.
Use an aluminum profile at least 2 mm thick to avoid bracket deformation when hitting water at high speed.
Step-by-step instructions for the manufacture of a transom bracket
The fabrication of the transom holder begins with a drawing or at least a sketch on paper that will take into account all the dimensions of your transom and sensor. Cut out a template of the future design from the cardboard, try it on the boat and make sure that it does not interfere with the engine and does not affect the cylinders. Only after approval of the layout, move on to the metal opening.
The vertical rack manufacturing process requires precision so that the sensor axis matches the plane of movement of the boat:
- Cut off the aluminum strip, equal to the height of the transom plus the margin for the sensor immersion.
- Drill holes for attachment to the transom, observing symmetry with respect to the center.
- At the lower end, fix the platform for installing the sensor itself, providing the possibility of adjusting the angle.
- Treat all sharp edges with a file so they don't hurt your hands or scratch the boat.
The sensor is often fixed by a plastic tube or a special plastic corner that is fastened to a metal rack, which allows you to easily change the position of the emitter and protects it from direct impacts on solid objects, the metal part performs the load-bearing function, and the plastic part provides safe contact with water.
☑️ Pre-installing check
The finished structure is recommended to be painted or anodized to give it an aesthetic appearance and additional protection. Many craftsmen use powder paint, which creates a strong and beautiful coating that is resistant to chips. However, even a simple layer of epoxy paint will significantly extend the life of the product.
Manufacture of quick-removal anchorages on board
If the transom is busy or the boat is not designed to be rigid, a quick-removal bracket on the cylinder is a great solution, and this system usually consists of two parts: a base that is attached to the boat, and a removable bar with a sensor, which allows you to quickly dismantle the equipment when you pull the boat ashore or transport.
The base for the onboard mounting is often a rigid plate made of fiberglass or durable plastic, which is glued or screwed to the transom part of the balloon. This plate is installed in the response part of the quick removal mechanism, for example, from tourist equipment or homemade pin lock, the main requirement is the reliability of the fixation so that the bar is not lost during the shake.
The sensor rod, in this case, is made of a lightweight but durable material, like a fiberglass rod or an aluminum tube. sonarAnd it's inserted into the base lock, and this design minimizes the metal's contact with the balloon, and allows you to adjust the depth of the sensor.
⚠️ Note: When installed on an inflated balloon, it is strictly forbidden to use sharp screws or screws that can damage the PVC shell; use only glue or soft screeds through protective petals.
You can use PVC adhesives or a soft-laced belt system to fix the base on the cylinder. The adhesive method is more reliable, but requires accuracy in application and time for polymerization. The belts are easier to install, but can shift during prolonged use, so they need to be checked periodically.
Comparison of materials for homemade brackets
The choice of material for a bracket directly affects its weight, durability and cost. The table below compares the main materials used by self-modelling anglers so that you can choose the best option for your conditions.
| Materials | Corrosion resistance | Weight. | Difficulty processing | Cost |
|---|---|---|---|---|
| Aluminum (D16T) | High. | Low. | Medium | Medium |
| Stainless steel | Very high. | Highly | High. | High. |
| Textolyte | Absolute. | Medium. | High. | Low. |
| PVC profile | Absolute. | Low. | Low. | Low. |
Aluminum is a middle ground, combining lightness and sufficient strength, but it is afraid of contact with copper and steel in water. Stainless steel is ideal in properties, but heavy and difficult to work at home without special tools. Textolite and plastic do not rust at all, but require careful design, as they can be fragile on the fracture on impact.
The Secrets of Working with Aluminum
When drilling aluminum, use lubricant (such as kerosene or special oil) to keep the drill from jamming and the hole is smooth. It is also recommended to groom the holes under the thaw so that the bolt heads do not interfere.
When using dissimilar metals, be sure to use rubber or plastic insulating pads, which will prevent the electrochemical corrosion that can destroy an aluminum bracket in one season, and choosing the right pair of materials or insulating them is the key to the longevity of your design.
Installation and configuration of the system on water
Installation of the finished bracket on the boat requires accuracy and adherence to the technology of attachment, especially if glue is used. PVC surface should be defatted with alcohol or a special cleaner, after which the glue is applied and the exposure time is maintained according to the instructions. For mechanical fastening, use wide washers or rubber pads to distribute the pressure.
Once the bracket is physically installed, you need to connect the sensor to the sonar and check it on the water, lower the sensor into the water and make sure that the cable is not stretched and has the free travel necessary to adjust the depth, turn on the sonar and check the readings at different speeds of the boat, paying attention to the noise.
Setting the angle of inclination of the sensor is a critical step, on which the image quality depends:
- 🎯 The surface of the sensor should be parallel to the bottom when the boat is moving.
- 🌊 When noise occurs at high speed, lift the sensor sock.
- 🔄 Avoid positioning when the sensor is looking up, otherwise it will catch reflections from the surface.
If you have vertical noise bands on the screen, try changing the depth of immersion or the angle of inclination. Sometimes the cavitation from the screw causes interference, in which case it will help to shift the bracket further from the diametric plane or increase the distance to the screw. Experiment with the position until you get a clear picture.
The main criterion for proper installation is the absence of noise at the maximum working speed of the boat and a clear display of the bottom and fish.
Check the condition of the fasteners and the integrity of the cable regularly, especially after winter storage. Over time, vibration can weaken the nuts, and ultraviolet light can make the insulation of the wire fragile. Timely maintenance will prolong the life of not only the bracket, but also the sonar itself.
Frequently Asked Questions (FAQ)
Can a metal bracket be attached directly to an inflated cylinder without protection?
It can't be completely. The metal can rub PVC, and when heated in the sun, the metal's contact with the polymer will cause the balloon to deform or burn, always use rubber pads, plastic linings, or put a bracket on a rigid base, which is then attached to the balloon.
How long should a sensor cable be for a homemade bracket?
The cable should be in reserve so that you can move the sensor freely and lift it when you go out in shallow water. Usually 1.5-2 meters from the mounting point to the display are enough, but it is better to measure the distance on your boat taking into account the route of the wire laying.
Do I need to remove the bracket when transporting a boat in a trailer?
It is advisable to remove the bar with the sensor, if the design is quick to remove, to avoid sailing and accidental impacts. the base can be left, as long as it does not interfere with the packaging of the boat in the transport bag and does not create pressure points on the material.
How to replace a special glue for PVC, if it is not at hand?
For temporary repairs or fastening, you can use two-component polyurethane adhesive or specialized adhesives for PVC boats (for example, based on polyurethane). Conventional superglue or silicone will not work, as they will not provide the necessary elasticity and strength of the connection.
Why does the sonar show the arcs of the fish, but not the bottom?
The sensor is likely to be too high or at the wrong angle, which causes the signal to bounce off the water surface, and it could also be caused by too high a speed of the signal or contamination of the working surface of the sensor with algae.