For any owner of a water transport, whether it is a small rib If you're a full-fledged boat, knowing the design of the hull is not just a theoretical bonus, it's a necessity. One of the key elements of safety and comfort is a recession. It's a constructive depression in the deck or transom of a boat that often goes unnoticed by beginners until it encounters real-world operation.
Understanding that, What is a boat recession?This article allows you to plan the placement of equipment, avoid flooding important sites and organize fishing properly. In this article, we will discuss in detail the design of this part of the housing, its functionality and methods of protection from the ingestion of off-shore water.
Issues related to tightness and drainage become critical when driving at high speeds or in conditions of heavy chop, which is why it is important to study in advance. design your boat.
Design features and the structure of the recession
A recession is a depression that can be located in different parts of the hull of a boat. transmutationIt's located in the stern of the boat, just in front of the transom, and this is where outboard motors are most often installed, and the recess is used to protect the lower unit and the propeller.
The second common type is deck-recessionIt can be a fishing pit or a tank niche, and it can be open, so it doesn't have any additional spray protection, or closed, it can have bulkheads and drain holes. aluminum boats The recession is integrated into the overall structure of the cockpit.
The depth and shape of the depression depend on the class of the vessel. In sports models, the recession is made as deep as possible to improve hydrodynamics, whereas in pleasure boats it often has a gentle shape for ease of movement. recession It directly affects the stability of the boat when loading.
The impact of the form of the recession on driving performance
The shape and depth of a recession can significantly alter the boat’s differentiation. A recession too deep in the stern without adequate compensation can lead to an oversubmersion of the transom, which will increase water resistance and reduce maximum speed.
The material of the performance also plays a role: fiberglass In boats, the recession is formed when the hull is formed, and in metal boats it is welded or riveted as a separate element, and the quality of the seams and joints in this area requires special attention when accepting the vessel.
Main purpose and functionality
The main task of a recession is motor protection And the propeller is damaged when you moor, pull ashore or move through shallow water, and the deepening allows you to lower the engine down while maintaining the overall clearance of the vessel, which is especially true for flat-bottomed boats.
The recession also serves as a function. water-shedWhen moving at speed, water floods the stern into the groove and, through special scupper holes, is removed overboard without pouring the main cockpit, without which the deck would quickly become a swimming pool.
Recession is not just a “pit” in the floor, but an engineering solution to protect the engine and efficient drainage, preventing the cockpit from being filled with off-board water.
It is also worth mentioning ergonomicsIn fishing boats, the recession is often used as a place to install anchor winches, fuel tanks or gearboxes, which frees up the center of the boat for comfortable fishing. PVC have removable paiole recessions that can be dismantled to increase usable volume.
The functionality of this zone is enhanced by the possibility of installing additional equipment, for example, in a recession, often mounting. sound-sensor Or transom sensors, protecting them from being hit by floating objects, which makes it easier to maintain and replace electronics.
Types of recessions depending on boat design
The classification of recessions is quite extensive and depends on the type of vessel. PVC-boat Most commonly, inflatable cylinder recessions or rigid plywood and aluminum inserts are easy and easy to install, but require careful handling.
In metal boat And the recess is an integral part of the hull, and it can be whole-welded or prefabricated, and it's focused on anti-corrosion treatment, because the recess is constantly being retained. Aluminum alloys They require high-quality painting or anodizing.
There are also cross-plate These are modern solutions that allow you to adjust the angle of the engine and improve the yield of the boat to planing, and these structures are often equipped with built-in water drain systems.
It is also worth highlighting recessions for twin-engineerIn such cases, the recess is complex, encompassing both motors, and requires a reinforced transom design, which ensures symmetrical loading and stable running.
The problem of flooding and methods of water control
Despite the obvious benefits, the recession has its downsides. floodingWhen moving against a wave or in sharp maneuvers, water can enter the boat through a recession faster than it can drain through the spigates.
To solve this problem are used self-evidentThey're valves that open under water pressure from the inside and close under the pressure of off-shore water, which prevents the fluid from flowing back into the cockpit.
Install additional ladders or mesh filters on the drain holes in the recession, which will prevent the system from clogging with algae and debris, which often cause water runoff to block.
It is important to monitor the condition drain-coopIf the recession is not self-draining, then after each fishing, you need to manually remove the accumulated water, and a forgotten cork can lead to an unpleasant surprise in the form of a full cockpit of water at the next launch.
In some cases, owners have established pump-pump It's a deepest point recession, and it allows you to pump water automatically when you reach a certain level, keeping the deck dry even when there are small leaks.
Instructions for preparation and operation
Preparing a recession properly before getting on the water is a guarantee of safe operation, and it is recommended to conduct a visual inspection of the area before each trip for damage, cracks or weakening of the anchorages.
Special attention should be paid to the cleanliness of the drain channels, garbage, sand and fish scales can quickly clog the system, turning the recession into a water reservoir. preventive cleaning It takes a few minutes, but saves you from big problems.
☑️ Checklist for preparing a recession for the season
When installing the motor, you must ensure that anticavitational It's at the right level relative to the bottom of the recession, and if you plant too deeply, you can flood the waters through the recession, even in calm water.
If you use a boat in salt water, after each unloading, be sure to wash the recession with fresh water. The salt, when dried, forms crystals that can damage the protective coating and accelerate the speed of the recovery. metal-corrosion.
Comparative table of specifications of recessions
To better understand the differences between the types of recessions, let’s look at their main specifications in a comparative table, which will help you choose the best solution for your problems.
| Type of recession | Materials | Weight. | Water protection | Application |
|---|---|---|---|---|
| Inflatable (PVC) | Dense tissue | Minimum | Low. | Inflatable boats, fishing |
| Hard (Phanera/Aluminum) | Metal/Tree | Medium. | Medium | PVC boats with NDNDM |
| All-welded | Aluminum/Steel | Highly | High. | Metal boats |
| Molded | Fiberglass | Medium. | High. | Sports and pleasure boats |
As can be seen from the table, the choice of type of recession depends on the material of the case and operating conditions. Fiberglass Metal and metal provide better protection, while PVC benefits in weight and transportability.
When choosing a boat, pay attention to the height of the side of the recession. High sides are better at protecting against splashes, but can interfere with the installation of certain types of equipment or make it difficult to get into the water.
Tuning and modernization of the recession
Owners often want to improve the standard design. A popular type of tuning is the installation. bulkhead Or lids that turn an open recession into a dry storage box, which is especially true for long hikes.
Another option is installation lighting Recession: Moisture-protected LED tapes not only improve the boat’s appearance at night, but also help control the condition of the water and the presence of foreign objects.
Tuning ideas
You can put removable plastic boxes in a recession that exactly replicate its shape, and that turns the storage area into a full-fledged organizer that's easy to extract for cleaning or carrying equipment ashore.
Some fishermen are in a recession. rod-pin It frees your hands and allows you to have a few gears on hand, and the key is to securely attach all the pieces so that they don't vibrate on the go.
The drain system is also in demand. spire or additional valves allows you to get rid of water faster, which is critical for active water sports.
Security and frequent errors
Ignoring a recession can have serious consequences, and one of the common mistakes is overloading this area with heavy equipment without taking into account the consequences of the recession. centre-upShifting the center of gravity in the stern can cause the transom to bury in the wave.
It is also dangerous to leave a recession open when there is a lot of excitement, unless it is equipped with reliable drains. Water can quickly fill the feed, disrupting stability. Safety at sea It requires constant monitoring of the water level in the body.
Never use a recession as the only place to store vital equipment (life jackets, first aid kit) without sealed packaging.
When installing the motor, make sure that the fastening bolts do not damage the structure of the recession, especially if it is made of compositeCracks around the fastener can quickly grow under the influence of vibration.
Check the leakiness of compounds regularly if the recession is part of a complex structure, and even a small leak can become a noticeable problem after several hours on the water.
Frequently Asked Questions (FAQ)
Should I grease the recession before every fishing trip?
Lubricate the recession itself is not necessary, but it is recommended to lubricate the moving parts of the motor fasteners and drain stopper mechanisms so that they do not acidify from contact with water.
Can you make a recession on your own on a PVC boat?
Yes, many owners sew additional PVC fabric linings or cut hard inserts from plywood, but it is important not to violate the tightness of the main cylinders and floorboards.
Why is there always water in a recession?
Most likely, the drain holes (spies) have clogged or the back valve has failed, and the drainage system must be audited and cleaned.
Does the recession affect the speed of the boat?
A properly designed recession improves hydrodynamics by reducing drag, but improper loading or water can, on the contrary, slow the boat.