The Soviet classic of water-motor sports, known as MKMIt still plys the vastness of our rivers and lakes, despite its venerable age, and was originally designed for a heavy stationary engine, making it stable but clumsy for modern fishermen, which is why tuning a MCM boat has become almost a must-have for those who want to get the most comfort and speed from the old metallics.
The owners of these boats have been developing unique solutions for cockpit remodeling, transaxing and lightening for years. The main goal of the upgrade is to turn a heavy barge into a lightweight glider capable of carrying a modern outboard motor up to 30-40 hp without risking stern tearing. In this article, we will explore the key stages of transformation, drawing on the proven experience of the boating community.
Before you take on the Bulgarian and welding machine, you need to make a thorough defect of the case. Often under the layer of old paint hides microcracks in the welds or corrosion, which can become fatal after removing excess weight. Security The water is above any racing ambitions, so you can not ignore the state of the metal.
Design analysis and planning
Boat. MKM It has a massive hull that was seaworthy initially, but created excess weight. The standard weight of a vessel is about 250 kg without equipment, which is a critical indicator for low-power engines. When planning tuning, it is important to understand which elements can be removed without loss of strength and which require reinforcement.
The first step is always to dismantle the stationary haunches and engine bay bulkheads, unless they are critically loaded. Freeing up the bow and stern space allows for the redistribution of crew and equipment weight. Many owners completely reconfigure the deck, turning the enclosed cockpit into an open, low-sided area.
⚠️ Attention: When cutting any elements of the power kit (spangouts, stringers), you must make an equivalent reinforcement of adjacent structures.
Particular attention should be paid granule In the runoff, it is designed to install a heavy stationary engine through a reverse gearbox, and to install an outboard motor requires welding an additional site or completely replacing the transom plate with a more powerful and adapted motor attachment.
Remaking the deck and cockpit according to drawings
The most time-consuming phase of modernization is the deck sheet. The standard configuration with high sides and a narrow passage is inconvenient for fishing and requires considerable effort to climb aboard. Tuning MCM boats often involves installing a new deck from the sea. fiberglass or duraluminum is less thick, but with well-designed ribs of stiffness.
The use of fiberglass allows you to create streamlined shapes that you can not get when working with sheet aluminum in garage conditions. The deck of composite materials is not only lighter, but also warmer, which is important for autumn fishing. However, you need to attach such a deck to the aluminum board through special profiles, avoiding direct contact of heterogeneous metals to avoid galvanic corrosion.
If you want to leave the aluminum deck, you need to redesign it, and the typical designs for the redesign suggest lowering the bow height and widening the cockpit, which improves visibility and makes it easier to pull out trophies. formoplasty The slacks that give the floor the necessary stiffness to twist.
- 🛠️ Cutting old piers and replacing them with a profile of stainless steel or durable plastic to protect the side.
- 🛠️ Organizing hand-helds under the seats for storage of gear, which frees up space in the center of the boat.
- 🛠️ Installation of transom plates with the ability to adjust the angle of inclination of the motor (trim) for better gleaming.
When cutting a new deck sheet, use only aviation aluminum brands. AMG5 or AMG6These alloys are highly corrosive and weldable, and the thickness of the deck sheet can be reduced to 2 mm if the longitudinal and transom ribs are welded from the bottom.
Bottom reinforcement and installation of the outboard motor
Putting an outboard motor on a boat that's designed to be a stationary engine requires an engineering approach, and the center of gravity shifts back, and if you just screw the motor to a thin sheet of stern, there's a high risk of transverses coming off or cracks. timber Or replace the stern bulkhead completely.
The bottom reinforcement method is often the stocking method, which is to insert an extra sheet of metal into the inside of the keel and the zygomatic bends, which not only increases the strength, but also changes the hydrodynamics, making the stroke softer on the chop wave. Some craftsmen weld longitudinal redans that help the boat to go sleeve faster.
Recommended thickness of the transom plate for the engine up to 30 hp: 6-8 mm (AMG5)
Transcent angle: strictly 90 degrees relative to the bottom plane (or 87-88 degrees taking into account the differential)
The important thing is to have a vomit-spur and seat mounts, and when you install a powerful motor, the load on the structure increases many times over, and all welds in the transom area must be made with both sides of the welding and cleaned to prevent moisture accumulation.
☑️ Control of transom amplification
Don't forget the system. differentiationBecause the weight of the engine is now outside the hull, the bow of the boat can be snatched, and this can be compensated by shifting the batteries and fuel tanks closer to the nose or mounting hydrofoils on the engine's lower unit.
Work with aluminum: welding and painting
The quality of the welded joints determines the durability of the entire structure. MKMThe ideal option is argon-arc welding (TIGIt produces a neat, durable seam with minimal thermal influence. Gas welding is also applicable, but requires high skill of the performer.
Before welding, be sure to remove the oxide film from the edges of the metal with a stainless brush. SvAMG6 If you don't have the skills to weld aluminum, you should leave that part of the job to the professionals, because it's too late to digest the cracked seam on the water.
Painting a boat is not just aesthetics, it's also an added protection. Aluminum doesn't rust like steel, but it's susceptible to oxidation and electrochemical corrosion. soiling (e.g., VL-023 or its modern counterparts) which creates a chemical bond with the metal.
| Phase | Materials | Tools | nuance |
|---|---|---|---|
| Cleanup. | Solvent 646, rags | Grinder, brushes. | Remove old paint to metal |
| ground-breaker | Grunt VL-023 (two-component) | Krascopult, compressor | Apply a thin layer, dry for 20 minutes |
| Painting. | Polyurethane or epoxy enamel | Valik, brush, spray gun | 2-3 layers with interlayer drying |
| Lacquer | Yacht lacquer (optional) | Brush | For UV protection |
⚠️ Warning: Never use lead-based soils with aluminum, which will cause instant and irreversible electrochemical corrosion, turning the bottom into a sieve in one season.
Structural Facilitation and Ergonomics
Weight loss is the main trump card of tuning MKMIf you replace the deck with a lighter one, you should give up heavy wooden cans in favor of foam seats, glass-covered seats, or inflatable cushions, which will also increase the boat's unsinkability.
The ergonomics of the cockpit have a direct impact on the fatigue of the fisherman, and the tilt chair on the pedestal makes it easy to control the motor and fish, but remember that any high seat shifts the center of gravity upwards, which reduces stability, and the balance between comfort and safety must be maintained.
The Secrets of Weight Loss
For maximum relief, you can use perforation in unloaded areas of the deck (closed from the bottom with transparent plastic) or replace steel fasteners with titanium elements, which are 40% lighter.
Storage of gear is another important aspect: the boxes built into the sides, the airtight boxes under the seats and the net pockets on the bulkheads keep the deck clean. A clean deck is not only beautiful, it's also safe, because it eliminates slipping and tangled fishing lines.
Use anti-slip paint or self-adhesive deck tape to make the cockpit interior, which will greatly improve safety when moving on a wet boat.
Improvement of driving performance and attachments
After installing the engine and reworking the deck, the boat may become too rolling or, conversely, too sharp. cross-plate (curved top edge) allows you to change the trim as you go, and a properly tuned plate helps the boat to go faster and keep smooth.
The attachments, such as sonars, navigators and rod holders, are vibration-sensitive. The aluminum case is good at conveying the sound of the running motor, so it's better to attach the electronic to brackets with rubber dampers, which will prolong the life of the appliances and eliminate unnecessary noise.
The final touch is the installation of a tent-transformer. MKM With its wide cockpit, the awning becomes a full-fledged roof that protects against rain and the scorching sun, the awning frame is better made of stainless pipes, and the cloth itself is made of reinforced PVC fabric, resistant to burnout.
Competent tuning of the MCM boat allows you to get the specifications of a modern plane for a fraction of the cost of a new aluminum boat, while maintaining the legendary strength of the Soviet hull.
Do I need to register a converted MCM boat in GIMS?
Yes, any design changes that affect the load capacity, passenger capacity or engine power formally require changes to the documents, but in practice, unless the appearance and basic specifications (length, width) have changed dramatically, owners often limit themselves to retaining factory license plates.
Which motor is best suited for a tuning MCM?
The optimal choice is a 15-25 hp engine (for example, Yamaha 15-20 or Tohatsu 18-25) which allows a boat with 2-3 passengers to plane confidently, staying within reasonable limits in terms of fuel consumption and weight on the transom.
Can the boat’s nose be completely sewn up on the deck?
Yes, it's a popular solution that turns a boat into a hood, but you need to provide emergency access hatches and ventilation so that the vapor of gasoline does not accumulate in the closed volume, which can lead to an explosion.
How to protect aluminum from fouling?
Use special unfouling paints for aluminum. Importantly, you can not use copper-based paints, since copper causes the strongest corrosion of aluminum alloys in sea and fresh water.