Legendary aluminum boat MCMThe Soviet-made raft still plows through rivers and lakes, but metal is not spared. The owners of these boats often face the need to upgrade, as the standard specifications no longer meet modern requirements for comfort and safety. The redesign of the MCM boat is a complex engineering process that requires accurate calculations and understanding of metallurgy, so as not to turn a reliable vessel into a pile of metal at the bottom of the reservoir.
Modern operating conditions dictate their own rules: you need to install a more powerful engine, increase stability and improve the habitability of the cockpit. Aluminum alloy AMg5MThe hull is highly weldable, making it an ideal candidate for deep modernization, but mindless intervention can lead to catastrophic consequences, so every step must be considered and justified.
In this article, we will discuss in detail the stages of transformation of the classic Kazanka into a modern small fleet. You will learn about the methods of strengthening the bottom, the nuances of the installation cross-engine A competent upgrade can extend the life of a boat for decades, making it competitive even against the backdrop of new factory models.
Analysis of baseline and defective shellBefore you take the Bulgarian, you need to conduct a thorough defect of the body. Boat ICM It has characteristic weaknesses that emerge after decades of use, and first look at welds for microcracks, especially around zygomatic flogging and bottom junctions. electrochemicalIt can be hidden under layers of paint and requires immediate intervention.
Pay special attention to the geometry of the bottom, if the boat has been standing on the shore for a long time without support, there could be a skew that, when you install a powerful engine, will lead to yaw on the course. longitudinal redane (if previously installed) and the timbers, any deformities must be corrected before major reinforcement work begins.
⚠️ Warning: Before starting reinforcement work, be sure to remove all residues of old paint and insulation to pure metal. Welding painted surfaces will lead to the porosity of the seam and instantaneous development of corrosion in the peri-seam zone.
Use an ultrasonic thickness gauge to estimate metal thickness. If the bottom sheets are less than 2 mm thick, you will need to completely digest the bottom part or install powerful linings. Ignoring this step can negate all modernization efforts, since the new engine will simply tear the thinned metal at high speed.
Body and body type reinforcementThe main problem of the standard configuration is the insufficient rigidity of the bottom when installing a motor with a capacity of more than 15 hp To convert the MCM boat under more serious loads, the installation of longitudinal and transom amplifiers is required. The optimal solution is the use of profiles from the aluminum-alloy similar brand, which will prevent galvanic pair during welding.
The reinforcement process starts with welding longitudinal stringers along the zygomatic lines and the diametric plane, which not only increases rigidity, but also creates a planing effect, improving driving performance. Cross-line frames, especially in the aft part, also require reinforcement, as they take on the load from the weight of the engine and the shocks to the wave.
☑️ Checking bottom reinforcement
It is important to follow the welding technology: use argon or special electrodes for aluminum, avoiding overheating. Overheated metal loses its strength and becomes brittle. Heat treatment seams after welding (forging or tempering) significantly reduce residual stresses, which is critical for the longevity of the structure.
The secret to strengthening zygomatic beads
When you increase the zygomatic bends, use a triangular section profile that is welded into the corner, which creates an additional keel effect, improving the stability of the course and protecting the sides from impacts on floating objects.
Modernization of the transom and installation of the motorThe regular transom of the MCM boat often cannot withstand the weight of modern four-stroke engines, the rework involves either a complete replacement of the transom sheet or its serious strengthening. sea-plywood 20-25 mm thick with subsequent aluminum sheathing, or transomation from a sheet thickness of 5-6 mm with powerful culling.
When you put a powerful motor in, the center of gravity shifts, which can cause differentiation in the stern. gas tank And the anchor box is closer to the nose, and you also need to have a reliable engine mounting pit, because the regular vents might not fit the modern fasteners.
Use rubber shock absorbing gaskets between the metal of the transom and the paws of the engine when installing the engine, which will reduce vibration transmitted to the body and reduce noise in the cockpit.
The table below shows the recommended transax gain parameters depending on the power of the engine being installed:
| Engine power (hp) | Transnant thickness (mm) | Enhancement material | Type of attachment |
|---|---|---|---|
| 15 | 3-4 | Aluminum AMG5M | Staff |
| 15-25 | 5-6 | Aluminum + Stringers | Reinforced bolt |
| 25-40 | 6-8 | Steel 09G2C (paste) | Through with washers |
| 40+ | 8-10 | Combination | Welded + Bolted |
Don't forget the height of the transom. Modern long leg motors may require cutting the top edge or, conversely, building up to keep the diewell in the water at optimum depth, and improper installation will lead to cavitation and overheating of the engine.
Improved stability and seaworthinessThe classic Kazanka is known for its rollingness, especially on the wave. MCM boat reworking often involves mounting a boat. wayboard This allows you to increase the width of the waterline and significantly improve stability, so you can make the bules from foam coated with glass fabric, or you can boil them from thin aluminum and foam inside.
Another effective way to improve driving performance is the installation hydrofoil It's also a way to get rid of the deadwell of the motor, or to form the developed zygomatic splash-blowers, which reduces yaw at full speed and makes the movement smoother, and it's also worth considering the idea of installing a nose-based deflector that will cut the wave.
⚠️ Attention: When installing overhead sides, strictly control the overall weight of the boat. Excessive weighting of the aft or bow can lead to uncontrollable yaw or, conversely, to burying the nose in a wave.
After installing boules or changing the shape of the feed, sea trials should be carried out with full load to ensure that there is no dangerous trim.
Cockpit and ergonomicsComfort on the water is not only about speed, but also about boarding, placing gear and staying overnight. The interior of the MCM boat allows you to turn a Spartan aluminum box into a cozy microboat. squishyThey serve as seats and storage spaces at the same time.
Fishing is critically important to have comfortable platforms, so you can cover the floor with moisture-resistant plywood with anti-slip coating or use special aluminum grooved sheets, which is not only more comfortable, but also safer, because it reduces the risk of slipping on wet metal.
The idea for a sleepover
Make removable soft backs for runduks, and if necessary, they are connected with special fasteners, forming a full-fledged two-person bed, covering the entire width of the cockpit.
Lighting and electrical wiring are another important aspect of the upgrade. light-belt This will provide a soft light that will not blind the eyes in the dark, and allow you to safely navigate the boat at night, all wires must be laid in corrugated and securely secured to prevent moisture and rubbing.
Finishing and corrosion protectionThe final step of the reworking is high-quality corrosion treatment. Aluminum is prone to oxidation, and if it's not protected, in a couple of years the boat will be covered with white plaque and spot sores. epoxy High zinc content, which creates a reliable barrier between metal and water.
Painting should be carried out in several layers, observing interlayer drying. Special unfouling paints can be used for the bottom if the boat is planned for long-term storage on the water. Zinc protectorsThe galvanic corrosion, installed on the transom and cheekbones, will provide additional protection against vagus currents and galvanic corrosion.
The quality of the pre-painting surface determines 80 percent of the success of corrosion protection, so don't waste time on cleaning and degreasing.
Remember the aesthetics: the right color and quality varnish will give your redesigned boat the look of a factory product. Regular care and washing after each outing will preserve the result of your labor for many years.
Can I weld aluminum MCM conventional electric welding?
No, conventional arc welding with steel electrodes for aluminum is categorically not suitable. Aluminum requires welding in an inert gas (argon) TIG or MIG, or the use of special aluminum electrodes with preheating. The use of steel electrodes will lead to a fragile and leaky seam that will quickly collapse.
What is the maximum power of the engine will withstand the converted MCM boat?
With proper strengthening of the transom and bottom, as well as the correct alignment, the MCM boat can safely carry a motor with a capacity of up to 30-40 hp However, it should be remembered that the rated carrying capacity is limited, and excess power can lead to dangerous differentiation on the stern and reduced stability.
Do I need to register the converted boat again in the GIMS?
Yes, if the changes are of a constructive nature (change of dimensions, installation of a new transom, change of power of the engine above the passport), the boat must be certified in GIMS. The tetalon will be changed, and only after that the operation of the modernized vessel will become legal.