C/O KELPIE
BOAT CARE
A
nother great addition to the low maintenance arsenal is
the range of modern marine sealants. Companies like 3M,
Sikaflex and Dow Corning have all created formulations that
either seal with relatively low adhesion, or super seal with
enough strength to hold a steel bulkhead in place.
The science of sealants is vast and fascinating, but the key
point is that they reduce maintenance by largely eliminating
the leaking of water into a boat’s substrate. They achieve this
by remaining flexible enough to cope with considerable
movement over the years, as well as with extremes of
seasonal and marine temperature.
A classic example is when it comes to
traditional teak decks, which are usually
laid over a flat or slightly curved substrate.
The traditional method is to secure the
teak planks on to a bedding compound
with marine-grade screws. Each screw
requires a rebated hole through the plank
and into the substrate beneath, and its
own teak capping-plug. The drawback is
that over time, the planks move, thescrews or plugs can loosen, and water gets under the planks
where it promotes the rotting process. Sometimes it leaks into
the accommodation below if screws have pierced the substrate.
Today, however, the teak planks (or pre-made panels) are
simply vacuum-bagged down on to a thick bed of a top grade
adhesive sealant, such as Sikaflex’s 298, which is then allowed
to cure. The gaps between are then filled with more adhesive
sealant before the whole thing is sanded back. The result is a
watertight, cushioned and flexible deck that lasts for many
years, with no screw holes, and absolutely no leaks to cause
rust or delamination, because the deck
beneath is unpunctured. If you are renewing
your teak decks any time soon, this method
should give them a much longer life. On an
older wooden yacht, where the planks may
have just been resting on cross beams,
restorers will often add an epoxy coated
plywood base, screwed or glued to the
beams to form a watertight substrate over
which they can lay a brand new – and
screwless – teak deck.SEALANTS
“The science of
sealants is vast
and fascinating,
but the key
point is that
they reduce
maintenance”Laying a deck using a flexible sealant should result in a watertight platform long-term