The legendary aluminum boat Ob 2. For many decades, it has remained one of the most popular boats in Russia, and the Siberian aluminum plant, which produced the first batch of these vessels, could not even imagine that it would create a real popular hit that would plow rivers and lakes half a century after the start of production.
The secret to success lies in the simplicity of design, maintainability and availability of the materials that make up the hull. Technical specifications of the boat Ob 2 It is a decisive argument when choosing the first serious boat, capable of withstanding the harsh conditions of operation.
In this article, we will take a look at all the nuances of the design, look at the real performance and stability, and discuss the typical problems faced by owners, you will learn why this project is so tenacious and whether to buy a used copy these days.
Design features of the body and geometry
The boat's hull is made of aluminum-manganese alloy, which provides high corrosion resistance and strength at a relatively low weight. The design is a riveted connection of sheets of skin with a set of frames and stringers, which gives the vessel the necessary rigidity without the use of welding, which could become a source of corrosion.
The contours of the shell are of the "deep V" type in the nose, which is a flat-skinned shape closer to the transom. boat Ob 2 It's a good way to keep the wave steady and go through the chop, which makes it different from the flat-bottomed kandak, but the presence of zygomatic splashers requires careful attention to the speed of cornering to avoid skidding.
⚠️ Attention: When you look at the used boat, pay special attention to the condition of the rivet seams in the nose and along the cheekbones, which is where leaks most often occur due to metal fatigue and vibration.
The transom plate is reinforced and designed to accommodate an outboard motor up to 30-35 hp, although the body can withstand heavy loads, and it is important to note that the factory equipment often did not include soft seats and windscreen, which owners purchased separately or made themselves.
Table of the main technical specifications
For those who are used to operating with exact numbers, below is a summary table with data-sheet figures. It is worth considering that the real values may vary slightly depending on the year of issue and the specific modification. Ob-2..
| Parameter | Meaning | Unit of measurement |
|---|---|---|
| Longest length | 4.15 | n |
| largest width | 1.51 | n |
| Height on midship | 0.65 | n |
| Mass of the hull with equipment | 145 | kilogram |
| Load capacity | 400 | kilogram |
The 400 kg load capacity allows you to comfortably accommodate three people with a full set of equipment or two with a significant cargo reserve. passport capacity It is designed for calm water, and overload in the wave can be critical.
Weighing 145 kg, the boat is heavy enough to be moved by a single person, but quite liftable for two, a trade-off between the strength of metal and mobility that owners of classic aluminum projects have to accept.
Capacity and layout of the cockpit
Interior space Ob 2. The cockpit is divided into three main compartments: bow, center and aft, and the bow compartment is often used to store anchor end and small inventory, accessed through a hatch or removable cover depending on the modification.
The central part is equipped with Bancami (seats), which serve as transom bulkheads, reinforcing the body, the layout allows you to accommodate three passengers, but comfortable landing can only be called conditionally, especially for long transitions. To improve ergonomics, many owners install additional soft linings.
The aft is reserved for the engine bay and the gas tanks, and there are also knobs that can be used to store life jackets or tools. centre-upto avoid excessive dispersion on the nose or stern, which significantly affects driving performance.
The volume of the cockpit allows you to place fishing equipment, a tent and even a small amount of prey, but you should not abuse the load. The aluminum side has a limited height, and when fully loaded, the buoyancy margin decreases, making the boat more roller.
Driving qualities and requirements for the motor
The boat's driving performance is directly dependent on the engine power and load, with a 9.9-15 hp engine. Ob 2. It is designed to be glissed with only one driver on board, and for a confident plane with two passengers and cargo, it is recommended that power from 18-20 hp.
At full speed, the boat is stable, but tends to yaw when sideways turbulent, due to its relatively narrow stern and bottom shape, and experienced boaters recommend not trying to reach maximum speed in unfamiliar waters.
To improve the plane output, you can install transax plates or a hydraulic lift on the engine's lower unit, which will reduce drag and improve handling.
Fuel consumption at cruising speed (about 25-30 km / h) with a 15-20 hp engine is approximately 6-8 liters per hour. This is quite acceptable for metal boats of this class, allowing you to make long exits without the need to carry canisters.
An important aspect is transmutationThe engine must be precisely mounted in height, the propeller's resistance too low, and the propeller's too high will cavitate in corners, and the optimum height of the anti-cavitation plate must be 2-4 cm below the bottom line.
Typical problems and maintenance
Despite the legendary reliability, the age of most boats is very high. Ob 2. The primary enemy of aluminum is not rust, like steel, but electrochemical corrosion and metal fatigue in riveting areas.
Owners often encounter leaks on the zygomatic stringer and in the nose, because when hitting a wave or during heavy operation, the tightness of the riveting joints is disturbed, repairs usually consist of replacing a leaky series of rivets with larger ones or installing patches.
⚠️ Warning: Never use steel or copper rivets to repair an aluminum case! this will cause instant galvanic corrosion and metal shattering around the repair.
Another problem could be the deformation of the transom plate, where if the previous owner had installed a motor that was more powerful than the recommended one, aluminum could swim. You can check the transom's condition by looking at the waves or cracks around the fastening holes.
To extend the service life, it is recommended to regularly lubricate the inner surfaces of the hull with special compounds that prevent oxidation, and keep the boat under a canopy. Direct sunlight and temperature changes also adversely affect the condition of the metal and sealant seams.
Tuning and popular improvements
Owners Ob 2. They often resort to modernization to adapt the boat to modern comfort requirements, and one of the most popular improvements is the installation of a windshield with sidewalls, which significantly protects against oncoming airflow and splashes.
It's also a common practice to install a steering console (coil or hydraulic steering) that frees the driver's hands and allows for more accurate control of the course, especially at high speeds. electric motors for quiet movement in shallow water.
☑️ Season preparation checklist
To improve safety and comfort, regular wooden baths are often replaced with cast aluminum seats with soft cushions, and the conversion of the nose hazel into a full-fledged trunk with a sealed lid will be useful.
Should I put on the Ob 2 engine 30 hp?
Technically, the hull will withstand, but the boat will be too prowling on the wave, and fuel consumption will increase disproportionately to the increase in speed, the optimal limit is 20-25 hp for comfortable operation.
Comparison with competitors and final conclusions
Compared to modern PVC products, aluminum boat Ob 2 It loses weight and dimensions in the transport position, but it gains in strength and durability, and it's almost impossible to puncture it with a snag or cut it against ice, making it ideal for the northern regions.
Compared to other Soviet-made metal boats (such as the Kazanka-M), the Ob-2 has more seaworthy contours, but is inferior in width to the cockpit, a choice in favor of driving performance at the expense of internal volume.
⚠️ Note: When buying a used boat, be sure to check the documents (GTE or sales contract). The absence of documents can create problems when registering with GIMS and registering.
In summary, it can be said that Ob 2. It is a workhorse that, if properly maintained, will serve more than one generation of fishermen, and its specifications allow it to solve a wide range of tasks, from fishing to transporting goods.
The Ob 2 is the best choice for those who value maintainability and strength over lightness and compactness, and are willing to put up with the need for a trailer or roof for transportation.
Frequently Asked Questions (FAQ)
What is the maximum weight of the engine can be put on Ob 2?
The manufacturer recommended motors up to 30 hp However, in practice, the owners put and 35-40 hp It is important to understand that increasing power above the norm requires strengthening the transom and increases the risk of breakage of the transom plate when hit by a wave.
Do I need to paint an aluminum boat Ob?
It doesn't make sense to paint aluminum with ordinary paint, it will quickly peel off. For protection and aesthetics, special aluminum soils (for example, epoxy-based) and special paints are used, often owners simply polish the metal or use anodized coatings.
How many people can the boat carry on the documents?
Passport capacity is 3 persons, however, when fully loaded with three adult passengers and cargo, the free-board stock becomes minimal, which can be unsafe when turbulent.
What is the difference between Ob 2 and Ob 1 and Ob 3?
Ob 1 is an earlier model with less slender contours; Ob 3 is a modified version with increased load capacity and a changed transom shape; Ob 2 is considered the "golden mean" in terms of seaworthiness and size.