Are all Mooring Buoys the same?

The short answer is a very big ‘NO’…….. There are a large variety of sizes, types, and colours of Mooring Buoys Available, not all of them are fit for purpose. What follows is a brief explanation on how to understand the various types, sizes and quality of Mooring Buoys that sailors with swinging or fore and aft moorings commonly use.

When Quality Counts

With over 30 years experience dealing with the needs and requirements of ‘mooring contractors’ – ‘mooring owners’ – ‘fairway committees’ – ‘yacht clubs’  – ‘fishermen’  and ‘harbour authorities’  we know how important it is for our customers to have a dependable mooring buoy holding up their mooring gear. We have supplied inflatable buoys manufactured by all the leading manufacturers, the product that has proved most reliable is manufactured by ……………. Castro of Spain. A visit to their website at is very worthwhile.

10 Tons!!!!

The only Tested and Certified Inflatable Mooring Buoy Centre available is designed and supplied by EYE Marine/Boat Gear Direct. We have been producing these Hot Dip Galvanised centres for over 15 years, they are designed to be used with the swivel section visible at the top of the Mooring Buoy which means that it can be inspected at any time. If necessary the complete assembly can be replaced with the mooring remaining in place. The ‘TITAN’ centre is available in three sizes, it has been destruction tested to over 10 tons and can be supplied as a separate item to fit any buoy with a 50mm centre. If you are using tested chain why risk using an untested buoy centre?????

These invariably consist of a bladder produced from injection moulded PVC using roto moulding machinery. The process for this type of Mooring Buoy creates the provision of a 50mm (2inch) centre hole through which a steel centre can be inserted. Mooring Buoy steel centres come in various types, EYE Marine/BGD have been manufacturing Mooring Buoy centres for over 30 years.

Also available as unsinkable Foam Filled Mooring Buoys

For a number of years we have been supplying ROPE Risers for specialist marine applications, for instance, companies using weather gathering buoys in extreme depths of water, where because of the depth, the weight of chain would cause the buoy to become submerged. We make these immensely long risers using POLYSTEEL 8 Strand Multiplait Floating Rope into which we incorporate a Heavy Duty Thimble, Wear Sleeve and Navy Dockyard Knowhow! Experience has shown that this type of ROPE Riser gives long trouble free service, is easy to maintain, and allows significantly smaller buoys to be used. 

We now supply an increasing number of mooring contactors with this rust free mooring buoy centre for use in river moorings. Alternative types of rope are also available. 

Also available as unsinkable Foam Filled Mooring Buoys

Types of Mooring Buoy

Bar Buoys   (Dhan Buoys)

All sizes have a 50mm center-hole going through the entire buoy,where any kind of rod with either flags, signs etc. can be mounted. Originally Bar Buoys were intended to be used as marker buoys with a flag mounted on pole for the fishing industry or as offshore area marking. However, these buoys are now very often used with various centres including a rod or rope. passed through the centre to create a mooring buoy.

Bar Buoys can be supplied either inflatable or foam filled.

Net Buoys  / Marker Buoys

As the name implies these buoys are primarily intended for use as either a buoy to hold up and mark a fishing net or to mark a lobster/crab pots. They are also suitable for use as a Mooring Buoy although there use is limited due to the fact that generally the eyelet is more suited to rope as opposed to a steel shackle.

They are often used very successfully as yacht fenders although it is most important to ensure that the rope eye is made of very a solid material. We are aware of many occasions when cheap versions are lost through the eye being sawn through by its tether.

Net Buoys sold by EYE / BGD all have very heavy duty rope eyes.

Generally used to allow the easy retrieval of the mooring buoy, it is attached to the mooring buoy by a tether preferably consisting of a floating rope. Common practice is to use this rope to provide the mooring buoy to boat  line.

Two very important points to remember:

Never use polypropylene tether line (very poor UV resistance)*

Best practice is to always use two tether lines.

* The best option is to use orange floating Polyethylene rope which is more UV and weed resistant

Pick-up Buoys

Unsinkable Hard Body Mooring Buoys

We originally introduced these Mooring Buoys to satisfy the demand for a an unsinkable buoy that was suitable for the harsh environment of small commercial vessels, since then they have been used for many other purposes, including the base for a variety of special marks, small Port and Starboard navigation marks and mooring buoys on trot moorings.

They have a UV stabilised Virgin Polyethylene body which encases a Closed Cell Polyurethane core. The HD tubular centre is Hot Dip Galvanised and will accept up to 20mm chain. There are alternative options for riser assemblies.

Elastomer Mooring Buoys

Regarded as the ‘Rolls Royce’ of mooring buoys they have a soft outer skin manufactured using a thick Polyurethane Elastomer which encases the inner core of closed cell Polyethylene Foam. If the outer skin is ruptured there will be no loss of buoyancy. The outer skin will not mark or colour fade. The recess at the top of the mooring buoy is to prevent any damage to the boat on wind/tide override it also provides a receptacle for the boat/mooring buoy tether.

The Hot Dip Galvanised tubular steel centre is manufactured to allow riser chain of up to 20mm diameter to be used, this will permit appropriate sites to accommodate larger sized vessels.

Available in three sizes

Inflatable Rod Buoy

Buoy Inflation Guide

Mooring Buoys including the valves are designed and manufactured to be inflated to 2.1 psi / 0.15 bar, unfortunately it is not always possible to be that precise. A good guideline is to inflate the buoy to until the walls are fully expanded but then make sure that you can depress the wall at least 6mm (1/4inch) with light hand pressure. Another method is to measure the circumference of the buoy to ensure that it is the same as the manufacturers specifications.

Buoy Size Guide

Mooring Buoy manufacturers give information relative to how much weight the buoy will hold up, this is generally described as buoyancy., this figure describes the point at which the top of the buoy will be level with the surface of the water. It is the total weight that the Mooring Buoy will support, the mooring buoy will not be visible above the surface.

Usable buoyancy is considered to be 60% of the stated buoyancy, e.g. if the buoyancy is given as 50kgs the usable buoyancy will be 30kgs. This will allow the mooring buoy to be visible for about half of its length.

Something else to consider. General advice for the length of the mooring riser chain is to allow 1.5 times the maximum depth of the water at High Water Springs, consequently when choosing the mooring buoy you will need to know the weight per meter of your chain and the maximum depth of water.

About Carlos Castro

It took Carlos Castro over a month to make his first buoy. An entire month to understand how a machine that had been delivered without any instructions worked. An entire month to invest all his knowledge of chemistry into obtaining an ideal mix of plastics. One month, one buoy.

Manufacturing floats was not Carlos’ profession. However, one day it would be and he would end up being a market leader but, at the time, in the early 1970s, the story had only just begun. The fragility of the aluminium and glass buoys used at the time and the fact that they did not last long at all was a constant source of problems for fishing vessels. The future lay in plastic products but whenever Castro had bought buoys from non-specialist companies there had been issues. The best – the only – way of getting the buoys they needed was to make them themselves.

Carlos knew all about working on the sea. His family was from Asturias and his father, Máximo Castro, was a master fishing net worker for cod fishing vessels. He had a profound connection to the sea and to the fishing industry. When Carlos was 10 years old, his family moved to Pasajes in the Basque Country and young Carlos began combining small jobs associated with the sea and his passion for cycling. He even competed in the Asturias road cycling race in 1963. But there came a time when he had to put everything into his work and he had to give up his dream of cycling for a living. From that point onwards, he dedicated his life to the sea and to fishing.

Carlos initially followed in his father’s footsteps and worked alongside him making fishing nets and learning all the tricks of the trade. Together, they perfected the art of trawl fishing and gained a profound understanding of each and every aspect of it, from the nets to the buoys, as well as the technical side of sailing. Then came the first fishing boat of his own. And the second. And the third, and so on until he ended up with a small fleet of five vessels. Carlos also worked as a fish wholesaler, dealing every day with 30 tons of produce that needed to get to the exchange at just the right time to get the very best price.

However, when he needed to fit out his own fleet of trawlers with buoys and floats he purchased the injection-moulding machine, fate would see to it that a new company was born.

Once they had worked out how to handle the machine, they manufactured their first series of buoys but found that there was an issue: they only needed 300 units and the machine could produce between 4,000 and 5,000 floats a month.

They decide to go ahead with manufacture regardless. They knew they were on to something special, that they had managed to make buoys that were not available on the market and that they were more durable than most. They knew all this because they were benefiting from all the advantages in their very own fleet.

It wasn’t long before the other fishermen in Pasajes wanted buoys manufactured by Industrias Plásticas Castro, too. These customers were swiftly followed by fishermen from ports all along the Cantabrian Sea who not only used the trawling technique but other fishing techniques too. Some of the products leaving the factory did not even have the company’s name or brand on them but that didn’t matter: everybody knew where they were from and everybody knew that the products leaving the Castro warehouses stood for quality. The orders kept coming in. The buoys earned the approval of the people who live off and for the sea, initially in Spain and then later in France. This approval later extended across Europe and they even began competing against other countries that had long-standing traditions of manufacturing plastic marine buoys.

They took the leap from the professional fishing industry to the marine industry. The experience they had gained through the sale of the products that were obtaining excellent results under terribly difficult conditions meant that they soon gained a foothold in this new market. Carlos, his sister, Mari Carmen, and her husband, Enrique Landa, work together. The three of them practically built the company from the ground up. They put thousands of hours, a lot of work and, above all, the trade of two generations who had lived off the sea into it.

Now, in 2020, Castro is not the same as it was 50 years ago. Nowadays, its products are sold right around the world in over 70 countries stretching from Australia to Canada and Morocco. The company has earned a degree of international recognition that was unthinkable in the early days.

Now, in 2020, the company can still be found in the same place where it was founded, in the Molinao neighbourhood right on the border between San Sebastian, a popular tourist spot, and Pasajes, a fishing village. Almost everything has changed since that buoy was manufactured in the mid-70s. The sea, the fishing industry, legislation and the vessels have all changed since then. With over 400 boats, the Pasajes trawling fleet was one of the largest in Europe and that has also changed, it now has under half a dozen vessels. The change in Castro, however, has been quite the opposite.

The company has continued to grow, so much so that is has become a world leader in the manufacture of marine and professional fishing equipment and accessories.

Its work ethic and continuous use of the trial and error method for obtaining optimum results in all products (nothing less will do) have contributed towards this growth. They have taken crucial steps forward for the benefit of the modern trawling industry along the way. For example, the Hydrodynamic floats with dimples that radically decrease vibration on the nets, or the Titanium floats made from a special alloy (Titanium Plastic) that means they can withstand depths of up to 3,000 metres.

Carlos Castro handed over control of the company to his sons, Raúl and Carlos almost ten years ago. They are the third generation of the family bound to the sea and its techniques. They grew up with the company at their side. First of all, they saw how their father ran it and then they started working there as soon as they were old enough. Both brothers have learnt about the business and worked in it from the bottom up. They started on the factory floor and in the warehouse, then moved up to the offices where they are now in charge of managing the company’s present and future. Both are acutely aware of their father’s formulas and lessons – the same lessons he also inherited from his father who worked with the fishing nets. The essence of the Castro business has barely changed since the very early days and it remains firmly committed to the reliability, precision and durability of its products. It was this commitment and determination that drove Carlos to spend a month setting up a machine in order to manufacture the buoy he had in mind.

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