Metal boat MKM Deservedly considered a legend of Soviet and post-Soviet boating sports, the model produced at the Xiaska Shipyard has become a benchmark for reliability for fishermen and tourists who value durable aluminum-magnesium alloy. However, when buying a used copy or planning to upgrade an old hull, owners often face a lack of accurate technical documentation. Knowledge of the exact dimensions is necessary not only for registration with the GIMS, but also for the calculation of a trailer device or the design of a new deck.
In this article, we'll go into detail about all the geometric parameters of the case, from the total length to the thickness of bulkheads. Many of the data that's circulated online is averaged or misplaced, which can lead to serious operational problems. We rely on factory specifications and real-world measurements to give you an objective picture. Understanding how mass and volume are distributed within contours is critical for safe operation on turbulence.
Particular attention should be paid to the fact that hull geometry Over the decades, it may have been altered by repairs or artisanal improvements by previous owners, so checking with reference values will help identify hidden defects or structural integrity. Below is a detailed analysis of all the dimensional specifications that will become your reference when working with this legendary boat.
General overall specifications and displacement
The basis for any calculation is an understanding of the total length and width of the vessel. Boat ICM The hull is designed to provide good stability even when fully loaded, with an overall length of 4.5 meters, which is the optimal size for transport on a standard passenger trailer without special permits for oversized. The midsection (the widest part) is 1.6 meters wide, which provides sufficient internal volume to accommodate three to four people.
An important parameter is the height of the side, which is the model MCM is equal to 0.72 meters. minimum buoyancyThe height of the vessel affects the sailing and behavior of the vessel in the side wind, and owners should consider that the actual height of the board above the water will depend on the load and the equipment installed.
The body weight without motor and equipment varies between 230-250 kg. This weight is considered acceptable for the alloy aluminum AMg5M, from which the skin and set are made. A unique feature of the design is the riveted connection of the skin with the set, which eliminates the risk of depressurization of welds during vibration. The total displacement at maximum load reaches 900 kg, which includes the weight of passengers, fuel, motor and equipment.
⚠️ Note: When measuring the length for the trailer, take into account the removal of the transom and the forehead. The actual length along the waterline may differ from the overall length, which affects the calculation of driving performance.
For a quick assessment of your copy's compliance with factory standards, check the baseline values in the table below. Small deviations within 1-2 cm are acceptable due to technological tolerances of Soviet production, but large discrepancies may indicate deformation of the case.
| Parameter | Value (mm) | Value (m) | Admission |
|---|---|---|---|
| Longest length | 4500 | 4,5 | ± 10 |
| largest width | 1600 | 1,6 | ± 10 |
| Height on midship | 720 | 0,72 | ± 5 |
| Empty boat sludge | 180 | 0,18 | ± 10 |
| Hull mass | 240,000 (g) | 240 kg | ± 10 kg |
Design features of contours and bottoms
Dough MKM It is designed with a keeliness that provides good germination on the wave and course stability. The angle of kileatity on the transom is about 10 degrees, smoothly decreasing to the nose. This geometry allows you to reach speeds up to 35-40 km / h with an outboard motor of 20-25 hp. It is important to note that the flat sections of the bottom (bones) have strictly defined dimensions, the violation of which during repair can lead to yaw on the course.
The bottom skin is 3 mm thick and the sides are 2 mm thick. The thinner metal used for the sides is due to the lower impact loads in this area. categorically not recommended We're going to use steel or thinner aluminum because it's going to disrupt the weight balance and corrosion resistance, and the junction of the sheets is actually covered and sealed with special compounds, which is a characteristic of the technology of the time.
The bow section has a trunk that allows you to fit the equipment for a multi-day hike. The bulkhead that separates the luggage compartment from the cockpit is also a set element that ensures unsinkability. If you plan to install a tank inside the housing, you should note that the standard size of the niche is designed for regular fuel tanks up to 50 liters.
transom plate and engine installation
Tranza MKM It is a critically important engine traction unit, with a height above the conventional bottom line (excluding the keel jet) of about 450 mm. This is the standard height for medium-power outboard motors. A modern long leg (L) motor may require a stretcher or a transom, as the standard cutout is for short leg (S) or transitional models.
The width of the transom along the upper edge is about 1350 mm, and on the lower (working) - about 1200 mm. the angle of the transom folding relative to the vertical (deferent) in a static position should be 3-5 degrees for optimal output to plane. If the engine is installed boat "pit" nose or, conversely, hoisting it, you need to adjust the position of the engine or the distribution of the cargo, and not saw the transom.
Mounting of the motor is carried out through special stops or directly to the transom board using rods. Trans strength allows you to install motors with a capacity of up to 30 hp, but the manufacturer recommended to limit 20 hp Excess power leads to overloading of the aft part and possible separation of the transom during sharp maneuvering.
⚠️ Attention: When drilling holes for an outboard motor mount bolts, use only stainless fasteners and be sure to seal the holes with polyurethane sealant. Water trapped in the transom causes hidden corrosion.
For those who are engaged in tuning, it is important to know the exact coordinates of the lower unit. The distance from the plane of the transom to the axis of rotation of the screw should be adjusted so that the screw is immersed in the water completely, but does not create unnecessary resistance. The standard distance from the bottom edge of the transom to the axis of the screw for the MCM is about 150-200 mm depending on the model of the motor.
☑️ Translation check
Internal layout and cockpit
cockpit MKM It's designed with ergonomics in mind for fishing and recreation, and the useful space of the cockpit is about 3 meters long, the seats (banks) are located across the hull and are often removable, which allows you to transform the space for overnight or transportation of large cargo. The width of the cockpit in the midfield allows you to comfortably accommodate two adults with your back to the sides.
The cockpit floor is usually made of wooden boards or plywood stacked on aluminum profiles, a solution that reduces cruising noise and improves thermal insulation. However, wooden elements require regular maintenance, and the size of the sleigh must be exactly the size of the interior, so as not to create stress points on the skin of the side when pitching.
In the bow, behind the trunk bulkhead, there are often additional compartments for unsinkability, and the volume of the cockpit allows you to place an inflatable mattress for two people to sleep. Inland altitude From the floor to the coamings (upper edge of the side) is about 0.5-0.6 meters, which is enough for sitting, but it will be difficult to get up in full height.
Shell materials and metal thickness
The main material of the case is an aluminum-magnesium alloy brand AMG5MThis material has high corrosion resistance in sea and fresh water, as well as good weldability. The letter "M" in the label means that the metal is in a soft (burned) state, which increases its plasticity. The thickness of the sheets, as mentioned earlier, varies from 2 to 3 mm.
The body kit (spangouts, stringers, flora) is made from the profile of the same alloy, but with a greater wall thickness to ensure rigidity. The elements are riveted on aluminum or dural rivets. The use of steel in fasteners is unacceptable due to the risk of galvanic pairing and accelerated corrosion of aluminum. Corrosion It is the main enemy of old boats, especially in places of contact with water and mud.
When repairing holes or replacing sheets, it is important to use the same grade material. Replacing with pure aluminum (AMz) or duraluminium (D16) will change the mechanical properties of the site. Duraluminum, for example, is stronger but less corrosion resistant and fragile. If you are not sure about the brand of the metal, you should consult a specialist or use universal aluminum solders and sealants to temporarily eliminate leaks.
| Element | Materials | Thickness (mm) | Type of connection |
|---|---|---|---|
| Underbody skinning | AMG5M | 3,0 | Rivet |
| Skin of the side | AMG5M | 2,0 | Rivet |
| Tranza | AMG5M/Tree | 3,0 / 20 | Rivet/Glue |
| Spangouts | AMG5M | 3,0 - 4,0 | Rivet |
Features of operation and modernization
Knowing the exact dimensions, owners often think about installing a tent-transformer or a running awning, the awning frame should be based on a linear fence or special racks installed in nests on the sides. MKM Often sold in finished form, but when sewing yourself, you need to take measurements from a particular instance, since geometry could “swim” for 40 years.
Modernization often involves sonar, navigation and lighting; wires must be laid in corrugated hoses protected from UV light; it is important not to disturb the sealed bulkheads when drilling holes under cable channels; any hole below the waterline or in the spray area must be carefully insulated.
The boat's storage also depends on its dimensions. MKM The height in the inverted state (including the keel and protruding parts) is about 0.8-0.9 meters, which allows you to store the boat in the garage or under the canopy, but requires reliable support to avoid deformation of the hull under its own weight.
⚠️ Warning: Do not keep the boat on point supports (bricks under the frames) for more than a month, this leads to local deformation of the skin. Use wide tapes or paddings along the entire length.
