Racing yachts, motor cruisers, lifeboats and pilot cutters - all types of repair undertaken. Our technical knowledge and practical experience encompass GRP, FRP, foam and Balsa sandwich construction in both polyester and epoxy resins.
The yard has considerable experience in the application of epoxy coatings to the hull of vessels. Osmosis prevention or Osmosis treatment is regularly undertaken with the yard operating as an approved treatment and application centre for Blakes Paints, International Paints, SP Systems and West Resins.
What is Osmosis
A polyester laminate may look watertight at first sight, but looks canbe deceiving. In the molecular laminate of the polyester there areenough crevices and holes through which moisture can diffuse in.
This process doesn't happen over night, but stretches over a period of many years. During this time, the individual layers of the hull laminate will resist the penetrating moisture in different ways. The gelcoat is the most watertight layer.This coat should never be damaged, since it prevents water and moisture from coming into direct contact with the laminate. If the laminate were in perfect condition,i.e. hte hull had been laminated without any air pockets or air bubbles, it wouldn't be such a big problem if moisture slowly penetrated the polyester.However, even the most perfectionist laminate technician will not be able to guarantee laminate that is completely bubble free. And now we come to the real problem, these bubbles may contain residue of the unhardened resin, curing agents, and binding agents made of glass matting.
The water (water molecules) which diffuses through the gelcoat into the laminate dissolves these residues in the bubbles. The concentration of these residues in the resultiing liquid is higher than in the laminate environment. This is when the osmosis starts, when the different concentration levels try to balance each other out. However, since pure water molecules are smaller than the molecules in the solution, these can also permeate the laminate more quickly and easily. The bubbles with the dissolved residues draw the moisture away from the laminate in the surrounding area and gather it in the bubbles. When the bubbles are full, they exert pressure and the osmosis bubble typically seen in the gelcoat are created.
How to identify osmosis
The firswt visual signs will be the formation of blisters in the gelcoat beneath the water line. If you pierce an osmotic blister the liquid contents will have a sour smell similar to vinegar. The problem may be discovered prior to its visual symptoms appearing by checking the moisture content of the hull with a moisture metre
Typical Osmosis Treatment
* Peeling Gel coat - To remove the defective Gel coat and Laminate
* Slurry Blasting - To open up the profile of the surface
* Steam Cleaning - To remove Glycol and Hygroscopic contaminants
* Drying - Natural \ Infra Red
* Application of coatings - In accordance with manufacturers recommendation.
Boat building and Repairs
Although now significantly reduced in number,
Amble Boat Company continue with wooden boat building, enabling the repair of
fishing vessels and yachts to be carried out at the yard.
In keeping with the epoxy coatings, Amble Boat Company operates
as an approved paint application centre for both Blakes Paints and International
up to 20.0m can have their topsides transformed with the application of a high
performance Polyurethane paint system, in a full choice of colours and providing
excellent gloss retention and scuff resistance.
A full marine engineering service is provided through our
experienced engineers, who possess considerable expertise everything from new
construction to on site repairs. Most equipment can be serviced or repaired including
engines, gearboxes, pumps, winches, generators etc. Amble
Boat Company are dealers for Yanmar, Caterpillar, Nanni, Mermaid Marine, ZF and Hurth
gears. We are also approved Volvo boat dealers.
range of inboard diesel engines range from 9 to 400 HP and are fully backed up
with spare parts through our Yanmar trained engineers.
Aluminium alloy, steel and stainless steel fabrications can be custom made to
Standing and running rigging may be purchased mail order or supplied and fitted
at your vessel.
wide variety "high and low tech" ropes are stocked from: 1.0 to 22.0mm
in diameter and splicing of rope ends can be undertaken in 3 strand, braid on
braid and wire to rope.