Transporting a long-distance swimmer requires a reliable and safe attachment, which is ensured by the correct selection of chassis elements. The choice of material of support elements is critical, because it depends on the safety of the hull of your boat and the durability of the trailer device itself in an aggressive aqueous environment. Incorrectly selected support can not only damage an expensive gelcoat or bottom, but also cause an emergency on the highway.
The modern market offers many different options, each with its own unique specifications and scope. roller-in Or what to choose from ready-made solutions to ensure maximum protection of the vessel when loading and driving on the road.
The main function of these elements is to reduce friction during the descent and ascent of the boat, as well as to evenly distribute the weight of the vessel in the transport position. Depending on the type of keel and hull material, the load on the reference points can vary, which requires careful approach to the choice of the vessel. polyurethane, rubber or plastic.
The main materials of manufacture and their specifications
The first thing that a boat owner encounters when they need to replace a boat is a variety of materials. polyurethaneThis material is highly wear-resistant, not afraid of ultraviolet, salt water and petroleum products, polyurethane cells are tough enough to hold the shape under load, but also have a certain elasticity, which is important for cushioning.
The second common option is rubber, rubber products tend to be softer than polyurethane, and they're great for sensitively coated boats because they minimize the risk of scratching, but rubber has the ability to age when exposed to sunlight, crack and lose elasticity over time, turning into crumbs.
The third option is hard plastic or polyethylene, which is often installed on trailers for heavy metal boats or boats with a deep V-keel, which provide minimal friction when slipping, but require a perfectly smooth surface to avoid damaging the body, plastic is most resistant to chemical stress, but less cushioning shocks.
⚠️ Warning: Never mix materials types on the same axle or padlock without consulting an engineer. Other rigidity of the supports will result in uneven weight distribution and may cause the boat hull to deform during long haulage.
Polyurethane vs. rubber: a detailed comparison
When choosing which supports to build or which to buy, it is important to understand the differences in the physical and chemical properties of materials. Polyurethane benefits in life: it practically does not wear off even when loaded on gravel or concrete slips, and rubber, especially cheap, can leave black marks on the light side of the boat, which is then difficult to wash.
In terms of price, rubber products are often cheaper, making them attractive for budget repairs of an old trailer. However, the savings can be false: if you actively use the boat on weekends, rubber supports will have to be changed every 2-3 seasons, whereas rubber supports will have to be replaced every 2-3 seasons. polyurethane They will last 5-7 years or more without losing their properties.
The temperature of the operation is an important aspect: rubber in the extreme cold bluffs and can burst when hitting the side, while high-quality polyurethane retains its properties over a wide range of temperatures. For regions with harsh climates, the choice of material becomes a matter of safety.
- 🔵 Polyurethane: high strength, durability, resistance to UV radiation, average price.
- 🔴 Rubber: softness, low price, tendency to aging and cracking, risk of contamination of the board.
- ⚫ Plastic: maximum rigidity, perfect sliding, suitable for heavy boats, low depreciation.
Design features: in the collection or separately
When deciding on a replacement, it is important to consider the design of the unit itself: supports can be supplied as ready-made units assembled with a metal sleeve and bolt, or separately - only a rubber or polyurethane part.kit) simplifies installation, as you get all the necessary fasteners, adapted to a specific size.
If you choose to make supports yourself or use universal consumables, you will need to accurately measure the diameter of the hole and the length of the seat. Standard dimensions vary, but the most common sleeve diameters are 17 mm, 20 mm and 25 mm. The mismatch in size will lead to backlash or inability to install.
The type of attachment deserves special attention. There are brackets with a vertical axis and horizontal, horizontal are more often used on the lateral beds, and vertical on the noserest (kielblock), replacing one type with another without digesting the trailer frame is usually impossible.
Can you make rollers yourself?
Theoretically, you can make cylinders out of technical rubber or thick polyurethane on a lathe. However, the cost of raw materials and work often exceeds the cost of a finished factory product. It is also difficult to ensure the necessary hardness and uniformity of the material in artisanal conditions, which will lead to a rapid failure of the homemade.
Influence of boat type on the choice of supports
The type of swimmer dictates its requirements. Inflatable PVC and RIB boats, soft contact is critical. Hard plastic or worn, hardened rubber is absolutely not allowed here. The ideal solution would be soft polyurethane rollers or special inflatable keel blocks that replicate the contours of cylinders.
Flat-bottomed aluminum boats ("Kazanki," "sparrows") require supports that will not slide over metal when cornering. Roller surface roughness is important. Smooth polyurethane can be too slippery, so sometimes composite materials with additives are chosen.
Deep-keel glass-plastic boats require rigid fixation, often using carpet-covered V-shaped kilblocks or rigid plastic stops, to prevent heavy hulls from moving sideways when braking sharply.
| Type of boat | Recommended material | Type of support | Features |
|---|---|---|---|
| PVC/RIB | Soft polyurethane | Cylinder/Walik | Protection of cylinders from puncture |
| aluminum | Polyurethane/Resin | Cylinder/Roller | Metal clutch, protection against corrosion |
| Fiberglass | Plastic/Carpet | Kilblock/Roller | Stringent fixation, weight distribution |
| Metal boats | Solid plastic | Roller | High load, minimal friction |
Instructions for replacement and maintenance
The process of replacing the support elements does not require a complex tool, but requires carefulness. Before starting work, you need to completely free the trailer from the boat and, preferably, turn it over or drive it onto the overpass to access the bottom of the frame.
To dismantle an old roller, a wrench of the appropriate size (usually 13, 14 or 17 mm) and possibly a penetrating grease of the WD-40 type are usually required if the bolts are boiling from salt. After removing the old support, inspect the metal bracket for corrosion and, if necessary, clean and paint it.
☑️ Checklist for roller replacement
Installation of new elements is carried out in reverse sequence. It is critically important not to pull the nut of the attachment: The roller should rotate freely on the axis, but without a strong backlash, and if you press it too hard, the polyurethane will deform, and the roller will stop spinning, starting to wear off when the boat moves.
Regular maintenance prolongs the life of the chassis. After each trip on salt water, the trailer should be thoroughly washed with fresh water. Once a season, it is recommended to lubricate the rotation axes with silicone lubrication, which does not destroy rubber and polyurethane.
⚠️ Warning: If you notice that the boat is moving sideways during transportation or you hear a knock in the area of the anchorages, stop immediately and check the nut tightening. The weakened roller may fly on the move, which will lead to the fall of the boat.
Frequent errors in selection and installation
One of the most common mistakes is to try to save money and buy the cheapest rubber bagels of unknown origin, often with an unpleasant chemical smell, stick to your hands in the heat and crumble after the first season. Quality material It can't cost three cents.
Another mistake is ignoring the condition of the metal bushings inside the roller, even if the rubber part is intact, a rusty or broken bushing will cause the roller to jam, so that when the boat is launched, it will not go down the rollers, but will scratch the bottom against the metal, leaving deep furrows.
Owners also often forget to change the side restrictive rollers, focusing only on the keel, meanwhile, it is the side supports that keep the boat from rolling in corners, and their wear can lead to dangerous tilt of the entire load.
Use a thread lock (blue Loctite or analogue) when assembling knots. Vibration on the road can unscrew even a well-tightened nut a couple of hundred kilometers away.
Where to buy and what to pay attention to when ordering
It is better to purchase components from specialized boating stores or official trailer manufacturers dealers. In markets and general auto stores, the range is often limited to low-quality consumer goods. When ordering online, be sure to check the articles with the catalog of your trailer.
Pay attention to the quality certificates and warranty card. A good manufacturer always indicates the hardness of the material (according to Shore) and the maximum load per roller. For heavy boats, this parameter is the determining one.
If you can't find original parts, look for universal counterparts, strictly observing geometric dimensions. In extreme cases, you can contact the companies that manufacture polyurethane products on demand, they will cut out the parts of the desired shape and hardness.
Properly selected and installed rollers are a guarantee that your boat will reach the water intact, and the descent will take a couple of minutes instead of an hour of fighting with a jammed bottom.
How often should I change the trailer?
The life of the polyurethane is dependent on the material and the frequency of use. Rubber rollers are recommended to be changed every 2-3 years or when cracks appear. Polyurethane rollers last 5-7 years. Plastic can last for decades if not mechanically damaged. Visual inspection is mandatory before each season.
Can polyurethane rollers be lubricated with oil?
Use of conventional mineral oils or solidol is not recommended, as they can destroy the structure of the polymer and attract dust that has turned into an abrasive. For lubrication of the axes of rotation, it is better to use silicone sprays or Teflon lubricants, which are inert to the polymers.
What to do if the film is not suitable in size?
If the hole is too small, you can drill it carefully, but not more than 1-2 mm, so as not to weaken the structure. If the roller is too large, you can try to undermine it, but it will violate the geometry. The best option is to order or buy the product exactly according to the specification of the trailer manufacturer.
How to replace the carpet on the kilblock?
The fiberglass rug on the keelblocks of the boats protects the gelcoat, and you can replace it with a special villous fabric for marine use or a quality synthetic carpet with a short pile soaked in water repellent compound, and the usual floor cloth will rot quickly.