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Boat fiberglass hull gealcoat finishing provides long-lasting and waterproof protection and improves resistance to salt corrosion and UV rays. However, over time, it tends to lose its brightness and to become matt.

This is why hull polishing is recommended every 3-4 years to remove stains and streaks due to time as well as abrasions brought about by rubber fenders.

To maintain the hull at best I suggest to take the boat aground by means of an appropriate scaffolding. Then, one of the first things to do is to wash the hull by using mild soap and a soft bristle scrubber to remove the surface dirt that covers small scratches to be filled to make the surface homogeneous.

To this purpose boat repair small kits are available. They consist in trowel-applied coatings followed by light sanding (120-240 and 300 grit paper). It is very important to apply the original boat colour as a different colour will make the area where the paint has been retouched more visible. Coloured tags are available on the market to identify the colour shade which is more similar to that of your hull. However, the best thing to do is to take as a reference the original code colour. This can be found in the Owner’s Manual or on the anchor hatch door or other cockpits. As an alternative contact the shipyard or the dealer.

Use abrasive paste to polish the hull. Put some paste on a cloth and on the hull using a variable-speed polisher. Select medium-low rotation speed although this will take some time and a certain strength to handle the tool. Apply the paste using a sponge pad or a lamb fur pad, even if it is better to use the latter for polishing purposes only. Application technique: make concentric movements with even pressure.

To remove very dirty stains, such as fender glue, first use a solvent (petrol or acetone), then polish the surface.

In case of timeworn boats or boats showing yellow deep streaks, polishing by using wet 1000 sandpaper is required. This is to remove thick gelcoat layers by abrasion and then treat in-depth stains.

In case of lacquered hulls, make sure a layer of transparent finishing has been applied. This is a polishable product which preserves painted surfaces from minor abrasions. In case of non-lacquered paint, use gentle soap instead of polishing products.

Let’s move now to how the teak on the deck can be preserved.

Teak is a long lasting wood as the silicon it contains makes it hard and resistant. However, its properties may be preserved only if it is taken care of properly as well as regularly maintained.

Teak regular maintenance requires more carefulness and constancy compared to hull polishing. Let’s see how to deal with teak preservation:

Once a year wash teak with a soft brush rubbing transversally to the wood vein (not from bow to stern). Paint strippers to be diluted with water, which help to wipe dirt away are available on the market, as well as experimental products containing oxalic acid and citric acid. The old teaching says, however, a seawater bucketful and a brush once a month is all you need!

Two or even three goes may be required. Be careful to non suitable products, as they may spoil fiberglass, skylights plastic parts or tapestries due to their content of seriously aggressive bleach. Also the seam rubber may be damaged and the seams, too, thus resulting in a stained deck, which is the reason why this aspect has to be carefully considered.

I suggest to clean teak surfaces using not only a scrubber but also abrasive sponges for hard-to-reach areas.

If teak shows protruding rubber, this has to be cut, then counterbore and homogeneously thin the teak surface of a few millimetres. Be careful the rubber perfectly adheres to the seam edges and has not become porous or crystallized. Please note that a good deck, if well maintained, can last over 20 years, with an original thickness of 12-15mm.

Although old-fashioned in modern boating, some boats could still have screwed teak decks. Should this be the case of your boat, both the covers and the screws of the deck slats have to be replaced. Replace the screws with shorter ones and seal the screw holes with some resin or butyl. Finally the teak cover are pressed onto the screw heads, the protruding part is chiselled away and then smoothed.  

Nails or screws in the seams, if any, have to be removed or smoothed using a Dremel tool as they can be very dangerous if you walk barefoot.

We have assessed together the main precautions to be taken to preserve hulls and teak decks. A proper attention and regular maintenance ensure longevity and durability to these two important elements of our boats.

Davide Zerbinati
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