FAQ

Several things are worth considering. If you need an inflatable boat for your yacht or motorboat, make sure you know the exact maximum dimensions of a boat that fits your yacht, as well as its maximum load capacity. The size of the boat is directly related to the maximum engine power and the maximum number of passengers.

If you plan to use the boat to tow a water skier, it should be fitted with an engine of at least 25 hp. In most cases the maximum number of passengers is given in the boat’s technical specification, but the actual number of seats may differ. First decide how many people you plan to carry, then check the actual number of seats. Take a look at the comparison table below and find the model that best matches your needs.

First, let’s talk about the materials used to build inflatable boats. To ensure maximum airtightness, the main material used for high-quality boats is 5-layer HEYTEX PVC (Germany):

• One central inner layer, making up about 20% of the total thickness, acts as reinforcement and is a fabric made of interwoven reinforced fibres.
• Two inner layers coat the fabric base with a sealed, flexible material, which makes it airtight and gives it a high level of adhesion to the base.
• The two outer layers are also made of an airtight, flexible material that provides resistance to wear and UV radiation and further improves airtightness.

The most common fibre-reinforced material is a polyester fabric base of 1100 DTEX density for standard boats and 1680 DTEX for professional boats. The flexible, airtight materials can differ, and this is the main factor in the choice. Today there are many different names and brands of boat fabrics, but they can all be divided into two large groups: elastomers and plastomers.

Elastomers are thermosetting materials, mainly various kinds of rubber. Two materials are the undisputed leaders among the elastomers used in boat building: HYPALON and NEOPRENE. They are usually used in combination: HYPALON as the outer coating and NEOPRENE as the inner coating. This combination is the most common for standard boats. A HYPALON coating (on both sides) is used only in professional applications and some commercial ones, where cost matters less than other properties of the material. One of the main features of this material is its high operating temperature (up to 140°C).

Plastomers are thermoplastic materials (they can melt when heated). The main materials in this group are PVC (polyvinyl chloride) and PU (polyurethane). PU has increased resistance to wear – it is an excellent material, but it is too expensive to be a leader. PVC remains the leading material for inflatable boats. You will find many different names for thermoplastic fabrics, but they are all PVC with minor differences in structure. Another important feature of PVC is its PRICE!

So when it comes to materials for inflatable boats, the choice is between HYPALON and PVC. Let’s compare the two in a table.

RIB: HYPALON or PVC?

In terms of basic parameters these materials are very similar. Modern technology and scientific progress in PVC production are gradually closing the gaps. From a practical point of view the most important differences are:

• TEMPERATURE RESISTANCE. Here HYPALON is clearly preferable in hot-climate countries (equatorial, sub-equatorial, tropical and some subtropical), where the surface temperature of the boat can reach 80–90°C. PVC is also quite common in those countries, but you need to be more careful when using the boat. In countries with a temperate or cool climate this difference disappears completely.
• SERVICE LIFE. PVC is more sensitive to UV radiation than HYPALON. However, special chemical additives used in PVC production have practically eliminated this problem – a 10-year service life of a PVC boat is more than enough.
• PRICE. Today HYPALON is 5–6 times more expensive than PVC. As a result, a Hypalon boat is almost twice as expensive as a similar PVC boat in the case of folding inflatables, and 40–60% more expensive in the case of RIBs. The difference is quite significant.

CONCLUSION: Buy a Hypalon boat if you plan to use it in a hot climate or if you are looking for a prestigious boat and price is not a concern. In all other cases a PVC boat is a much better choice.

Folding boats are the classic example of inflatables, going back to the first rowing dinghies and military rubber boats. Of course, modern inflatables are far more advanced: they now have engine transoms, reinforced floor panels, V-shaped hulls and many other remarkable features. Everything is great except one thing: the floor. It is still soft!

Sometimes this is an advantage and sometimes quite the opposite. A soft floor lets you moor at a deserted shore without worrying about possible damage – because the bottom of your boat is soft! All inflatables fold up and are easy to transport once deflated. Great! But…

But folding inflatables can only dream of the qualities of rigid inflatable boats (RIBs).

A RIB is a combination of an inflatable and a traditional boat – something in between.

RIBs let you combine all the advantages of an inflatable with those of a traditional boat while eliminating all their drawbacks. It is a quite successful and promising achievement.

Take this, for example: a boat with a soft bottom creates more drag in the water than any heavier rigid material such as metal or plastic, which means an inflatable is not the best choice for racing. Rigid-hull boats reach the highest speeds. Another factor is the comfort and stability of a rigid-hull boat. Folding boats are great for sport and recreation when you need nothing more and simply want the easiest option. A rigid-hull boat, on the other hand, offers full comfort; it is much better suited to that.

Next: setting up! If your boat has a rigid hull, you won’t have to strain your muscles before every trip – everything is ready, you just inflate it and off you go!

A rigid-hull boat is not just a different kind of boat; it is a completely different kind of fun. In practice many people become fans of such boats once they try them. Of course, these boats are more expensive and heavier, take up more space and need more maintenance, so it is worth considering this option carefully.

RIB: HYPALON or PVC?

In the boat catalogue you can compare all Golden, Silver and Drive Line models — by length, number of people, engine power and price. The “To scale” mode shows the real difference in boat size.

In fact there are three main selection criteria: the brand name (make), the engine itself and the length of the engine leg (shaft). The choice of brand depends on personal preference, taste, the specific market situation and so on, and will not be discussed here. We will, however, gladly give you information about the engine, as well as about choosing the shaft length and such important points as engine tilt and balance.

What engine power is best for your boat? Every boat has one key characteristic, Pmax (maximum power). But that does not mean you should install the most powerful engine. We would like to explain and suggest the 3 most typical choices you can make:

Your choice

economical

optimal

extreme

Engine power as a % of the permitted maximum power

40 – 60%

60 – 80%

80 – 100%

Level of safety on board

High

Very high

Acceptable

Maximum speed as a % of the maximum possible

up to 60%

up to 90%

100%

Fuel consumption

Low

Optimal

Highest

The ECONOMICAL choice – engine power is about 60% of the maximum possible for your boat. It is truly a choice of economy and safety. With such an engine the boat is quite slow with a full tank but easily reaches 60–70% of the maximum possible speed.

The OPTIMAL choice – engine power is about 80% of the maximum possible. Here you get: the highest level of safety on board, reasonable fuel consumption and almost the maximum level of performance (a 10% difference from the maximum doesn’t matter unless you want to race). This significantly extends the life of your boat. With this engine choice the boat will perform in the best possible way. We recommend this as the best and most optimal choice for you!

The EXTREME choice – engine power reaches 100% of the maximum possible power for the boat. With this choice your boat will work AT THE LIMIT: of safety, consumption and so on. This is primarily a racing choice, but also for those who love extreme situations, wind in their hair and generally take EVERYTHING out of life! It is a truly amazing experience, but only if you have enough boating experience.

Less than 40% of engine power: it is also possible to use a boat with an engine that has less than 40% of the maximum power. But only if performance isn’t important to you and you like to enjoy other things. Nature is so beautiful if you don’t disturb it too much!

Engine power above 100%: using a boat with engine power higher than the permitted maximum is illegal and dangerous. Think twice before deciding, because your life and the lives of those in the boat with you depend on it. Using a boat with an overpowered engine will void the warranty and may cause serious legal problems.

You will find the engines matched to each model on the Yamaha Engines page.

The right engine shaft length is usually given in the manual supplied with the boat. The shaft length is standard and can be as follows:

Engine shaft length

Required transom height

Short shaft

381 mm / 15″ (short)

Long shaft

508 mm / 20″ (long)

Extra-long shaft

635 mm / 25″ (ultralong)

After installing the engine, check that everything is in order: the engine’s anti-cavitation plate should be 25–50 mm lower than the lowest point of the transom.

Usually every outboard engine comes with a standard propeller. Some engine suppliers sell them separately, so when buying you should ask the seller. Without clarifying this you may get an unpleasant surprise.

In fact it is practically impossible to give one universal piece of advice on which propeller your boat needs, because it depends on many factors. This kind of question is best left to professionals, but if you decide to choose the propeller yourself, follow these steps:

Install the engine and let it run for 10–12 minutes until its output returns to normal. Load the boat with the expected number of passengers and check the revs at full throttle at top speed.

If the maximum revs are lower than required for your engine, REPLACE THE PROPELLER WITH ONE OF LOWER PITCH and check the revs again. If the required revs are reached too easily, even with less than full throttle, you should CHOOSE A PROPELLER OF HIGHER PITCH and check the revs again. Try to choose the propeller so that you get the best performance at full throttle, but in any case avoid overloading the engine with a propeller of too high a speed (large pitch).

For practical reasons it is best to have at least two propellers: one for heavy loads (small pitch) and one lighter (large pitch).

Remember: the boat should be inflated only after it has been fully assembled. Every inflatable can consist of several inflatable parts, such as a multi-chamber tube, an inflatable floor or an inflatable keel. The following inflation order is required: boats with a plywood floor and inflatable keel:

TUBE ⇒ KEEL;

boats with an inflatable floor and inflatable keel:

TUBE ⇒ FLOOR ⇒ KEEL.

The tube always has several chambers (compartments) separated by a flexible partition. The order in which the tube is inflated is very important. The basic rule: WORK FROM REAR TO FRONT — that is, inflate the rear chambers first and then the front ones. For example, remember that the only correct way to inflate a three-, four- or five-chamber tube is as follows.

Important to remember: inflate all chambers except the front one to 90% of the nominal pressure. Then continue inflating the front chamber until the nominal pressure is reached. Because the chamber partitions are flexible, inflating the last, front chamber to nominal pressure will loosen these partitions. As a result, inflating the last chamber automatically raises the pressure in all the other chambers to the nominal pressure. Pay special attention to closing the valves tightly after inflating the boat.

Remember that without tightly closed valve caps the pressure cannot be maintained for long.

How do I adjust the inflation level and the trim of the boat?

Adjusting the inflation level and trim of the boat is very important for owners. The reason is simple: the combined weight of the engine, helmsman, passengers, fuel tank and luggage is much greater than the weight of the boat itself. So how do you ensure balance? The rules are very simple:

Try to distribute the whole load evenly along the length of the boat. Avoid piling load at the rear of the boat.

Engine – mounted on the transom, it should not be moved.

Helmsman – if you have a tiller-steered engine, the helmsman is most often at the rear of the boat. The best solution is remote steering, which can be installed in the middle or at the front of the boat. If that is not possible, you can use various kinds of extended tillers. This solution is not as effective as the previous one.

Fuel tank – some engines have a dedicated place for the fuel tank. Often, however, you can choose your own location for it. To balance the front and rear of the boat it is best to put the tank at the front. This solution is especially effective when the boat is empty and the fuel tank full. Of course it is not necessary if the fuel tank is empty.

Passengers – to keep the boat balanced, spread the passengers evenly across the whole boat and prevent them from moving around.

Luggage – should be placed only in the front part of the boat. Remember to cover it with a blanket to protect it from spray while sailing.

Speaking of handling an inflatable boat, it is worth saying a few words about planing mode and how to reach it. What is it? To understand it you need to understand how a boat moves through the water.

There are three most common modes of a boat’s movement on water: DISPLACEMENT MODE, TRANSITION MODE and PLANING. Let’s try to go through them.

DISPLACEMENT MODE. In this mode the boat is either standing still or slowly floating on the water. In this case water resistance is low.

PLANING. At this stage the boat rides on top of the water thanks to the hydrodynamic lift generated by the contact of the boat’s bottom with the water. Water resistance at this point is minimal, which allows the maximum speed to be reached.

TRANSITION MODE. This stage is the transition between displacement and planing. Have you ever seen a jet plane taking off? It is similar. To enter transition mode you have to push the throttle fully (or almost fully) open. If the engine is powerful enough, the boat will take off at once and its bow will rise (almost like an aeroplane). At this moment water resistance rises to its maximum, because the bow of the boat lifts, forming the largest angle with the water (this position is called the “hump”). After this mode the boat will start to glide over the water and will move fast and lightly.

Look at the illustration.

The figure shows the engine power needed to reach various speeds. The greatest resistance is clearly visible. Once the maximum is passed the boat goes onto the plane. From that moment less power is needed to maintain speed. This means the boat needs more power to reach 10 km/h (6 mph) than to reach 15 km/h (9 mph). Does that sound paradoxical? No, it is true.

In the transition phase the boat’s bottom has more contact with the water than during planing, which means greater resistance and more power.

Every boat is very sensitive to the tilt angle of the engine leg. If this angle is not right, performance drops and the boat becomes more dangerous. By changing the mounting angle, try to find the best option: the most stable engine position.

A) When the engine is set too low, the bow of the boat drops and there is a lot of splashing.

B) When the engine is set too high, the bow of the boat rises, the hull has little or no contact with the water, balance is lost and the risk of capsizing increases. Air gets into the propeller, which leads to propeller ventilation (cavitation).

C) Optimal trim: the boat runs smoothly and fast, in sufficient contact with the water, while the engine leg is in a vertical position.

The phenomenon of ventilation, often confused with "cavitation", means air getting into the propeller. At the same time the engine speed (rpm) rises and becomes higher than normal. You probably know the characteristic “engine roar” sound in sharp turns or in other similar situations. Remember that ventilation is harmful to the engine and significantly reduces passenger comfort. Here are some reasons for ventilation:

Cause

Solutions:

Incorrect engine leg length or transom mounting.

Check that the lowest point on the bottom of the boat (closest to the engine leg) is at least 25–50 mm higher than the engine’s anti-cavitation plate.

If this distance is shorter, you will have to mount the engine lower or use an engine with a longer leg. When it comes to ventilation the rule is: THE DEEPER, THE BETTER!!!

Incorrect engine mounting angle: engine leg raised too high.

If the bottom is loose, the flow of water under the rear of the boat is disturbed, which causes ventilation.

To solve this problem, check that the bottom is well tensioned.

To do this: inflate the tube and the keel of the boat to nominal pressure, and check that the floor or inflatable bottom is firmly attached.

Folding boats: the bottom is not tensioned enough.

If the bottom is loose, the flow of water under the rear of the boat is disturbed, which causes ventilation.

To solve this problem, check that the bottom is well tensioned.

To do this: inflate the tube and the keel to nominal pressure, and check that the deck or inflatable bottom is tight.

Incorrectly balanced load in the boat – overloaded bow.

Do not overload the bow of the boat. Incorrect balance can also make the boat move incorrectly.

Swell

Slow down and pay attention to the balance of the boat. Don’t rush!

Of course, you can simply attach a tow line to the towing eye at the front of the boat and set off. That won’t be a problem if you only have to cover about 100 metres. But if you have to cover a longer distance on open water and use this method, there is a high probability that the towed boat will not be behind you when you reach your destination. So how should you tow a boat? What is good and what is bad?

• Basic towing. This is the worst possible method. It should only be used at low towing speeds (up to 5 km/h), in windless weather, over short distances and under constant supervision. At higher speeds the boat may lose balance and start to sway, which can damage the line, the boat itself, or even capsize it. Be careful.
• Intensive towing. Here the tow line is connected to the boat with a knot or towing loop, and the line is attached to two towing points on both sides of the tube. This method completely eliminates uncontrolled movements of the boat and makes it possible to tow without problems at maximum speed. We recommend this method as the main one.

The safest and most suitable way to tow a boat in a storm. We recommend this method because it is best for long trips on the open sea. Under this method the ends of the line pass through the towing rings at the front of the boat, run under the bottom and are fixed directly to the transom. It is the most durable and reliable way of towing a boat. Even ordinary towing points are quite strong, but in storm conditions the risk of unexpected jerks grows, which can damage the towing points. It is better to use stronger towing points on the transom.

If you have to tow another boat. Attach a loop to the towing points on the transom and connect it to the main tow line with a metal ring or eye, or in some other way, so that the main tow line moves freely along the loop. This will let you stabilise the moment, especially when changing direction.

Unfortunately, the reason for such strictly regulated safety rules on inflatable boats was the large number of accidents. According to statistics, many people have drowned in oceans, seas and lakes because of their own negligence. We therefore recommend:

FIRST: PREVENT ALL POSSIBLE HAZARDS YOU MAY ENCOUNTER.

SECOND: YOU MUST BE READY TO ELIMINATE THEM IF THEY APPEAR. “Being prepared” means having all the equipment necessary to ensure safety, knowing how to behave correctly in danger, and strictly observing the safety rules. The best way to learn water safety rules is to attend special courses. We will try to tell you about the most important points.

Personal flotation device – life jacket.

Life jackets must be reliably available on every boat, in accordance with all the laws of conduct on the water in every country in the world. There are many different kinds: a swimming vest with neck support, an inflatable jacket with neck support, a light jacket without neck support, rescue equipment to be thrown directly into the water: cushions, horseshoe buoys, inflatable rescue clothing (jackets, trousers, etc.).

To buy reliable and legal personal flotation devices, it is better to contact their official distributor and state your requirements for life-saving equipment. In any case they must have an official quality certificate. REMEMBER, YOUR CHANCE OF SURVIVAL DEPENDS ON YOUR CHOICE OF LIFE-SAVING DEVICES.

Navigation lights and signalling devices.

Driving a boat without navigation lights is, first, foolish and, second, illegal. Check the condition of your lights and keep them in good order. Learn the local rules of navigation so that you have no trouble deciphering signals. Also check that you have all the necessary permits for signalling equipment, since they differ from country to country. Don’t forget sound signals, such as whistles, signal horns and visual distress signals (signal flares, smoke flares, or even an ordinary flashlight), which you must have on board.

A full cover is very important for your boat. It protects against rain and dust. But above all it should protect the inflatable tube from abrasion and damage – that is its main function. To extend the life of the boat we recommend high-quality boat covers. Usually all inflatable boat manufacturers offer protective covers as an option.

GRAND can supply covers for every boat model, from the smallest to the largest. You also have another option – ordering a cover anywhere else – but then the following should be taken into account (from our experience): the cover must protect the entire surface of the boat, including the bow cones. It is better to use stronger fastenings than rubber loops, eyelets and the like, which do not secure the cover 100%. This matters when you tow your boat on the motorway. All edges and corners of the cover must have additional fixings.

The material the cover is made of must not let water through, but at the same time it must let air through. Using a “non-breathable” cover is not the best solution, because it can lead to a build-up of moisture, which is harmful to some parts of the boat and its interior equipment.

As for the colour of the cover, consider that in direct sunlight the temperature under the cover rises, so white is the better colour. But then it is not practical at all, because the cover gets dirty quickly. That is why in a hot climate light grey is the best option. Pay particular attention to the quality of the fabric and the durability of its colour. If you are careless, your boat can be damaged with no chance of restoring it to its original condition.

The best way to transport RIBs, and even camping boats, is to use a trailer. With the right trailer, all operations involved in transporting the boat become simple and safe. How do you choose the right trailer? Here are some tips:

The size of the trailer and its load capacity must match the dimensions of your boat and its weight. Check your boat’s parameters according to the manual. Choosing a larger trailer will be a mistake, because every time you drag your huge trailer onto the beach you will be reminded of the wrong choice.

The larger the surface of the hull and the contact area with the trailer, the better. It is better to choose a trailer with many rollers and large longitudinal beams. Longitudinal beams are better than rollers, because the contact area of rollers is much smaller than that of beams. The rollers or beams should be matched to the shape of the boat.

The keel line is the best contact point and at the same time the strongest in the whole hull. It is better to buy a strong trailer with strong springs and large galvanised wheels for use in the coastal zone.

Once you have chosen the right trailer, here are some tips on how to use it: the boat must be properly inflated. When transporting the boat on the trailer, use the front towing point for RIBs and the side points for folding boats.

Lower the engine leg and fasten it to the support on the trailer. Carefully secure the boat with straps using the front, rear and side towing points. If you have to transport the boat over long distances, use a cover for it to avoid scuffing and various damage to the tube and hull from stones and dust met on the way.

Taking care of the boat in such conditions is very necessary – it can rain at any moment. At the very least you should be prepared for it. To avoid surprises, follow a few simple rules: securely moor your boat to a dock or a floating pier every time you leave it on the water;

Learn a few easy nautical knots to secure your boat.

This will save time (you don’t have to take the boat out of the water every time);

Raise and secure the engine;

If you can, take the tank and the oars out of the boat;

Remember to cover the boat with a tight-fitting cover.

It is better to use the standard covers for your boat (see the boat accessories list);

If you intend to leave the boat in the water for a long time in the sun, you should slightly reduce the pressure in the tube and the other inflated parts of the boat. This will reduce the risk of damage to the boat due to the rise in pressure caused by temperature.

Choose a dry, shaded, heated room with a stable temperature to store the boat. If possible, it is better to unfold the boat and inflate it slightly. That will be the best way. If this is not possible, we recommend unpacking the boat from time to time (every 2–3 months) to check it. Do not twist a folded boat: the fewer wrinkles, the better. Try to make as few folds in it as possible. Of course, during storage the boat must be clean and dry. Try to store all parts in which water may remain (cushions and other fabric accessories) separately, in a relatively dry place.

Of course, the best option is not to leave the boat outdoors (imagine your favourite boat under snow). But that is only advice. And if you still (unfortunately) have no other choice, remember:

Low temperature. Low temperature does not damage the fabric (the lowest operating temperature of most boats is down to -30°C), but there are limitations: because the fabric loses elasticity at low temperature, a problem appears when moving and folding the boat. In that case you must first warm it up indoors.

Cover. A standard cover is not enough for long-term storage. It should be larger, with more free space around the boat for ventilation. The size of the cover should allow the whole boat to be covered completely, not just its upper part. A quite good idea is to build a kind of frame around the boat for the cover, which will look like a canopy – a small house for the boat for the winter.

Trailer. If the boat is on a trailer, try to put it on some solid and stable support to take the load off the wheels and springs.

Engine. In winter you have a great opportunity to take the engine to a workshop for technical servicing. In any case, do not leave the engine in the boat outdoors in winter; it is better to remove it.

Compared with wooden, aluminium or fibreglass boats, inflatables need more maintenance. But with proper maintenance and care you can fully enjoy your boat and its capabilities. In fact, caring for the boat after use is not difficult, but it significantly extends its life. During storage keep the boat clean and dry. Proper maintenance and repair is the best way to enjoy your boat for a long time.

It’s not difficult at all! The hardest thing is to make yourself do it. Wash and dry your boat every time you take it out of the water. After taking the boat apart, wash it and all its parts with plenty of soapy water.

If the boat is too dirty, use special products to clean it (preferably marked for PVC or polymer). Do not use solvents, acids or other chemicals not intended for PVC and resin. This may damage the boat and is not covered by the warranty.

Use a cotton cloth or sponge to clean the boat to avoid mechanical damage while washing it.

Do not apply much force when cleaning the boat; its material is very susceptible to damage. After cleaning, always dry the boat. The sooner the better. If the boat stays damp for a long time (especially in a warm place), the wooden parts, coating, paint, anodised material and so on may be damaged.

To avoid serious problems with the boat, never dry it in the sun, especially when it is strongly inflated. Before drying, deflate the boat, leaving a little air in it to keep its shape.

All wooden parts of inflatable boats are made of special marine plywood or waterproof wood. All are coated with special marine paint, varnish or laminate. Such paints and coatings are also very water-resistant. During use, small cracks or scratches may appear on painted and laminated parts, after which water gets into the wood and it starts to swell. If the plywood is intended for marine use you don’t need to worry, because its layers are glued with a special waterproof adhesive.

Therefore damage to the varnish or laminate is not harmful to the boat. But if you care about the look of your boat and its durability, then in the end it is better to repair it.

To do this:

Check the condition of all wooden elements at the end of the season. Mark all damaged areas.

Dry all damaged parts in a well-ventilated, dry place.

Apply 2–3 coats of special marine paint to the damaged places; for painting it is better to use two-component polyurethane paints, because they are the most durable.

There are three main metals used in boats: stainless steel, brass and aluminium. The main drawback affecting metal wear is corrosion. Stainless steel is the most resistant to corrosion and needs no additional coating. For marine use various kinds of alloys and stainless steel are used, and they all have a different degree of corrosion protection, as well as a different price. For example:

Alloy 316 (DIN) – or A4: one of the best alloys, which never rusts.

Alloy 304 (DIN) – or A2: it may rust a little after prolonged use, but it can easily be removed from the surface with ordinary detergents without abrasives. The price is acceptable.

Brass is also quite well protected against corrosion, but basically all brass parts are nickel- or chrome-plated. On the one hand, a brass product resembles stainless steel in appearance. On the other hand, it is additionally protected against oxidation (when oxidising, brass gets dirty and stains quickly).

Aluminium is not as resistant to corrosion as stainless steel or brass. That is why an additional protective layer is required. Most often in such cases an anodised coating is used, which mechanically prevents corrosion. All other methods (painting, varnishing and so on) are not as effective.

You will notice immediately when the anodised coating has worn off:

the aluminium takes on a dirty look. Unfortunately, if this happens there is nothing you can do about it. Anodising aluminium (and plating brass) is done only in industrial conditions. So if the protective coating on the parts has deteriorated or corroded, the best solution is to replace them.

Pay particular attention to corrosion of electrical equipment. In this case make sure that different metals do not touch each other (for example brass and aluminium), because with such contact an electrolytic reaction occurs immediately, which has a more harmful effect than ordinary corrosion.

On boats and inflatables you can find quite a few different plastic parts: oarlocks, oar stops, oar blades, valves, handles, handrails and so on. They may be made of different plastics such as PVC, polypropylene, polyester, synthetic polymers, etc.

The main problems with plastic are:

Surface cracks, loss of colour and clouding under UV radiation.

Irreversible deformation of the surface. All kinds of plastics have no crystalline structure and most often undergo plastic deformation during long-term use.

Keeping plastic parts clean greatly extends their life, but does not protect them from damage completely. Mostly all kinds of plastics contain special additives that increase resistance to the harmful effects of UV rays and can slightly delay ageing of the material. Be careful when choosing chemicals for cleaning plastic, because improperly cleaned plastic can be seriously damaged. If you want to use something other than ordinary soapy water, make sure the cleaner you use is suitable for the kind of plastic being cleaned.

On the market you can also find so-called “restorers” (chemicals) that can temporarily improve the look of plastic. Unfortunately this effect is only temporary. You should also be more careful with restorative products containing silicone, because:

Surfaces coated with silicone-containing reducing or cleaning agents are much less receptive to bonding.

Very often silicone can be the main cause of seams coming apart. If it gets into a joint, the ability of the plastic to bond is greatly reduced. The best way to prevent this problem is to protect the boat from UV rays with a canopy and shorten the time the boat spends in direct sunlight.

As for fibreglass, the problem is similar to the previous case. The decorative gelcoat found on all fibreglass parts can be polished to a mirror finish with special polishing products. When treating fibreglass with such products, pay attention to their content of solvents and other active chemical elements. They can dissolve the gelcoat and damage the mould.

With any electrical equipment there is one main problem: corrosion can cause damage. Although most electrical devices have an anti-corrosion coating, contacts often remain stained as a result of oxidation. In salt water the problem is of course worse. Caring for electrical equipment is not difficult: you need to make sure the contacts are as dry as possible.

We recommend placing all contacts in flexible conduits. Check all cable bases and connections for corrosion. If you find anything during the inspection, be sure to clean that spot. Check the battery mountings. Dry, wash and tighten. Open and clean the navigation lights, check that no water gets inside and check that the bulb works. Bulbs should be replaced every season. If you use conventional switches rather than automatic ones, the relevant fuses should be checked periodically. It would be nice if you changed them every season.

Your boat, like any means of transport, needs repair from time to time. The less you look after it, the more problems you will have with it. The variety of possible damage is very wide: from a small puncture to complete destruction. And each problem needs a special approach to solve.

The more serious the damage, the more professional help is needed. Of course, in the case of particularly serious damage, professional repair at a service centre is necessary. But in fact most damage can be repaired in non-professional conditions.

When using an inflatable boat it is very important to know how to repair minor failures, because they can happen at any time and it is not always convenient to contact a professional. So let’s try to work out how to do it.

You should always have a toolkit if you are going on a boat trip. The most necessary tools:

Pieces of material of various sizes, to put patches on damage to the boat when needed (they can be taken from the boat’s repair kit or bought separately from the dealer). 10–15 patches is enough. Make sure these pieces are made of the same material as the boat (PVC or Hypalon).

Two-component adhesive (100 ml) suitable for your type of boat (PVC or Hypalon). Check that the tube of adhesive is full and well closed. Read the instructions for use carefully.

A small polyethylene container for preparing the adhesive mixture.

Medium-sized brushes (1–2 pieces).

Small scissors, a knife or blades.

Waterproof sandpaper and masking tape. None of this is hard to take with you; the main thing is not to forget it!

Damage to the inflation valve is one of the most common faults. The problem can differ: loss of the valve cap, air leaking through the inlet valve, air leaking in the gap between the valve itself and the boat’s tube. In most cases the only solution may be to replace or reinstall the valve. You can do this at a service station or do it yourself (in the latter case you will need special tools to replace the valve).

To remove the valve you need to:

deflate the boat

firmly hold the valve nut in the boat’s tube (perhaps even with something mechanical, like a vice), but take care not to damage the tube itself.

Fit the valve-holding mechanism and unscrew the valve body from the nut, which must stay inside the boat’s tube.

When dismantling is finished, check the condition of the valves for damage, cracks and deformation. As a rule, it is better to use a new valve as a replacement.

To install the valve you need to:

Put the valve nut inside the tube, or use the old one if it is in good condition (it is enough to wash it).

Apply marine-grade sealant to the valve threads and to the areas that touch the tube.

Screw the valve body into the nut by hand. Then tighten it more firmly, holding the valve nut through the tube (as when dismantling).

Leave the valve for 24 hours to let the sealant set.

Check the seal with soapy water.

Air leakage is the main problem faced by owners of inflatable boats. Air pressure gives the boat its firmness and reliability; if you lose it, you lose the rest. There are no inflatable boats that are 100% airtight! Air leaks happen in every boat. The question is how much air is lost. How exactly do you determine how much air has been lost?

If the pressure drops by less than 20% a day, your boat is fine; this is an acceptable rate. Such a boat can stay without additional inflation for up to 3–5 days. If the pressure drop is more than 20% a day, you should pay particular attention to such a leak. Such a boat goes soft in less than 1–2 days.

So far soapy water has been the best way to locate an air leak. 1. Prepare a mixture: mix liquid soap and water 1:1. 2. Inflate the boat to the maximum permitted pressure. 3. Apply the mixture to the whole surface of the boat to test it. If there is a leak you will find its location immediately: you will notice a trickle of small bubbles. Often the source of an air leak is very small and hard to detect. Use the following search pattern:

INFLATION VALVES=>CROSSED SEAMS ON THE TUBE=>ALL CROSSED SEAMS=>ALL LONGITUDINAL SEAMS=>FABRIC SURFACE.

Explanations:

• about 50% of all air-leak problems are caused by the inflation valves, and the main problems are valves not closed with the cap, loose or unsuitable or deformed caps, and damaged sealing rings.
• about 20% of all leaks originate in the seams.
• about 30% of leaks occur on the fabric surface: various kinds of damage (small punctures, cuts) and damage from abrasion. Once you have located the source of the leak, mark it with a permanent marker and clean the surface for repair.

A few words about adhesive in general. First, the adhesive you intend to use must be suitable for the purpose. You can buy it from a boat distributor or in a specialist shop. Depending on the material your boat is made of, you will need PVC adhesive or Hypalon adhesive. These are different adhesives. Make sure you make the right choice for your boat, and read the instructions before buying any adhesive.

Adhesive can be one-component or two-component. So what is the difference?

One-component adhesives are most often multi-purpose. They are easier to use than two-component ones. However, the stability of a one-component adhesive is not as high, especially in hot weather.

Two-component adhesives contain a second component, the so-called “hardener”, which stimulates polymerisation of the adhesive and thus increases its reliability and the thermal stability of the joined elements.

Our recommendations: – for light, short-term repairs use a one-component adhesive if the damage cannot be repaired with a two-component adhesive. – in every case a two-component adhesive is preferred. Use it as the main one.

The technique for applying adhesive to a tear is quite simple:

Locate the damage and choose or cut a suitable patch.

Prepare the adhesive mixture: mix the hardener with the adhesive in the required proportion and stir thoroughly. The proportion of hardener is always given in the adhesive’s instructions. Most often the proportion is about 4–5%, that is 4–5 parts hardener to 100 parts adhesive. Use the mixture within 1 hour at most, because it dries quickly.

Mark the boundaries of the bonding area on the boat with masking tape to reduce adhesive consumption.

Carefully clean and wash both bonding surfaces. If you have a Hypalon boat, make sure you have sanded the bonding surface on the boat and the patch with sandpaper until the surface is completely matt (this is not necessary for PVC).

Apply the first thin coat of the prepared mixture to both surfaces and let it dry for 20–25 minutes.

Apply a second thin coat of the prepared mixture to both surfaces and let them dry for about 5 minutes.

Remove the masking tape, place the patch on the previously marked spot and press it down.

Place the finished item on a hard, flat surface and press the bonded spot down as firmly as possible. Use a metal roller or another cylindrical object (glass bottle, various rollers) for this.

Leave the boat at rest for 2 days without inflating it. If you are doing an urgent repair, leave the boat motionless for at least 2 hours and then inflate it to minimum pressure. After 2 hours the seams have 70% of their strength, which may be enough to reach your destination if you sail carefully.

Punctures and scratches can result from abrasion or direct piercing. Since this is not serious damage, you can repair your boat with a single patch on the outside. When choosing the patch size, remember: it should be at least 12–15 mm larger than the damaged area. This means the diameter of a patch for a puncture must be at least 25 mm. For scratches the patch should follow the shape of the scratch plus 12–15 mm around it.

Cuts are quite serious damage. The best way to deal with this is to glue on two patches, one inside and one outside. If placing the inside patch is problematic, stitch the cut with nylon (polyester) and glue on only the outer patch. The patch should extend at least 25–40 mm beyond the area of the cut. Cuts up to 50 mm can be repaired with an ordinary toolkit. If the damage is large, it is best to leave the repair to professionals at official service centres.

For gluing components of the boat, follow the standard gluing guidelines. No special recommendations are provided. The only problem is finding suitable accessories (seat zip, lifting and towing points, etc.). We recommend contacting the dealer for clarification.

Seam damage is one of the most serious problems. Seams can be repaired only at service centres. In case of unforeseen seam damage:

Try to put patches on the outside to keep it airtight;

Add as much adhesive as possible, as much as can harden;

Do not inflate the tube too hard; keep the pressure as low as possible while still being able to make slow headway, and stay close to the shore;

Contact a service centre as soon as possible for professional repair.

If you own a boat with a rigid fibreglass hull, a few words on fibreglass repair are for you. The technology of fibreglass repair is not complicated, but professional knowledge and skills will not go amiss. For this we recommend contacting professionals to repair damage to the hull. With non-professional work you can do even more harm.

But if you still want to try, we will give you a few tips. Fibreglass is a combination of two main components: polymer and the glass fibre itself. For a better look every kind of fibreglass is covered with a decorative outer layer – gelcoat (a kind of polymer). The polymer itself is liquid in appearance, but after the hardener is added it becomes incredibly hard.

There are two most common kinds of polymers:

epoxy and polyester.

Polyester is one of the most commonly used materials in the marine industry for boat hulls. So if you have a rigid inflatable boat, 95% of what you have is polyester. It is very important to know what polymer your boat is made of before starting repairs, because different kinds of polymers do not mix well. Pay attention to this when buying a boat.

Fibreglass manufacturers produce it in several types: glass roving (glass fibre wound onto spools), glass mat and glass cloth. Glass roving is used mainly in industrial machinery, while glass mat and glass cloth are suitable for ordinary repairs. A few general recommendations on the most common defects:

Gelcoat scratches. If the scratches are not deep (up to 0.2 mm) but you are worried about the look of the boat, you can simply sand it with sandpaper (800, 1200, 1500) and polish it with a special product to a mirror finish. If the scratches are deep enough and the gelcoat layer is badly damaged, you need to clean the damaged surface and apply a dose of gelcoat (you can get it in any specialist shop and from the dealer – don’t forget to check the colour!!!), and then it has to be sanded flat and polished to a shine.

Cracks and cuts in the hull. Defects of this kind are quite difficult to repair, and special knowledge is required in this case. If you notice cracks or cuts in the hull, it is best to seek qualified help from a service centre.

Open the 3D configurator, choose the model, colours and equipment, then transfer the configuration to a quote. You will see the price of each option, the engine and the trailer, the net total, VAT and gross. You can download the PDF offer after entering your contact details.

Prices are calculated at the current EUR/PLN rate and the manufacturer’s price list. We confirm the final price in the commercial offer – the offer has an expiry date. Options that have appeared in the 3D configurator but are not yet in the price list are priced individually.

Yes. After you choose a Yamaha engine, the configurator automatically applies a package discount – separately on the boat, options, equipment and engine. You will see the amount of the discounts straight away in the summary.

In the configurator, in the step “Equipment and engine”, in the field “Do you have a discount code from us?”. The code activates individual price terms visible only to you.

Yes. You can arrange financing of the boat, engine and trailer online with our partner GO-Leasing: submit a lease application. Attach the PDF offer from our configurator to the application – it contains the full quote for the chosen set.

Private customers (without a business): call a GO-Leasing consultant – you will see the phone number after opening the link. The consultant will choose a form of financing for a private person.

Yes, we issue a VAT invoice for every sale. The company GERMANTON Sp. z o.o. is an active VAT payer (NIP 5862342126).

1. Configure the boat in the 3D view.
2. In the summary click “Copy the configuration link”.
3. Paste the link in the field next to the 3D view and click “Transfer to quote”.

The colours and equipment go into the quote together with the prices.

The manufacturer’s 3D configurator is updated more often than the price list. We add new options to the offer once the price is confirmed – they will not be left out.

Yes – the link from the 3D configurator contains the whole configuration. Keep it or download the PDF offer.

We hand over boats from stock straight away. Boats built to order according to your configuration usually take 12–16 weeks from the deposit, depending on the model and the season.

At our showroom and service centre GRAND BOATS Poland – Topolowa 5, 84-207 Łężyce (Tue–Fri 10:00–18:00, Sat 10:30–15:00, Sun 10:30–13:00). We can also arrange transport on a trailer or delivery to an address of your choice.

Yes – we fit the engine, rigging and electronics, start up the whole set and hand the boat over with operating instructions.

Without a qualification document you may drive a motor yacht with an engine of up to 10 kW (about 13.6 hp) – for example the smallest Silver Line inflatables with a small engine. For a boat with a more powerful engine you need a motorboat licence (motorboat helmsman), issued by the Polish Motorboat and Water Skiing Union.

The exemption for yachts up to 13 m and 75 kW applies only to craft whose speed is limited by design to 15 km/h – RIBs with an outboard engine do not meet this.

Basis: Art. 37a of the Inland Navigation Act; analogous thresholds apply at sea. Before setting out, check the current regulations and local restrictions on the water body.

Yes, if the boat is longer than 7.5 m or has an engine of more than 15 kW (about 20 hp) and belongs to a Polish owner. Smaller boats can be registered voluntarily – this is useful, for example, when travelling abroad.

Registration is handled by a single nationwide register, REJA24 (since 1 August 2020, under the Act of 12 April 2018 on the registration of yachts and other vessels up to 24 m in length); you can file the application at the county office (starostwo) or online. The registration document is of unlimited validity. When you buy, we give you the full set of documents for registration: the invoice, the CE declaration of conformity and the engine documents.

• VAT invoice,
• CE declaration of conformity and operating manual,
• warranty card for the boat and the engine,
• CIN number (hull identification number).

GRAND boats come with a 2-year warranty. Yamaha engines have a 3 + 2 year warranty (5 years in total) – the detailed terms are set out in the Yamaha warranty card. We handle warranty claims in Poland, at our service centre in Łężyce – you do not have to contact the factory.

Yes – we import GRAND parts and accessories directly from the manufacturer. You will find popular items in the shop.