by Jim Westcott
will a plastic boat differ from a fiberglass boat?
plastic kayaks are polyethelene or polythene and are produced using a
process called roto-molding creating a substantially cheaper and very
durable kayak. Many manufacturers are giving a fancy name to their
plastic material for marketing purposes but most are realistically
pretty similar. The negatives are that plastic kayaks are often
substantially heavier, will distort easily in heat, will scratch much
deeper and are therefore noticeably slower than the same kayak in
fiberglass. They are however, an excellent choice for knocking about in
the surf zone or rock gardens and will perform reasonably well for most
other aspects of sea kayaking at a much more affordable price.
How is a kevlar boat different from a fiberglass boat?
Kevlar kayaks are made using a sandwich of fiberglass and kevlar
fabrics bonded together with vinylester resin. There is almost always a
fiberglass cloth of some type as the outside layer(s). Because kevlar is
much higher than fiberglass in stiffness and tensile strength, the
builder can use fewer layers of cloth and in turn use much less resin
reducing weight by approximately 15-20%. Kevlar is much more expensive
than fiberglass and much more difficult to repair. It can be easily
recognized by it's gold color.
Will the kevlar boat be
faster than the fiberglass boat?
Not enough to be very
noticeable. In fact they often can be much more affected by high winds
while day-tripping. Unless you are an avid racer, the best reason to buy
a kevlar kayak is the advantage of lighter weight when loading and
unloading onto your car and carrying the kayak to the beach. If these
reasons are not an issue, save yourself a bundle and get a fiberglass
kayak. You can get some really nice accessories with your savings!
Will a kevlar boat be stronger than a fiberglass boat?
The short answer is no! This is in part because they use
substantially less material in the kevlar kayak to reduce the weight.
Kevlar is very high in tensile strength but relatively low in
compressive strength. An all-kevlar boat would show initial damage
fairly easily from a hard blow. The damaged cloth might stay together
even though much of the resin around it will have fractured. If you
expect to use your kayak in the surf zone or around rocks, kevlar is not
a good material choice.
How is a carbon fiber kayak
different from a fiberglass or kevlar boat?
There are a
few manufacturers building "carbon fiber" kayaks. These kayaks are also
typically a sandwich of fiberglass, carbon and other cloths. You can
tell the carbon fiber by the jet black color resulting from the process
used to make the cloth. They are almost always left visible by using a
clear resin to the outside showing off the hi-tech fabric. Carbon cloth
is very stiff (stiffer than kevlar) but lower in tensile and compressive
strength. The advantage to carbon is the chance to use even less
material than a kevlar boat resulting in even less weight. These boats
tend to be very costly and brittle.
What are the
characteristics for a carbon/kevlar kayak?
Many of the
manufacturers from Europe are producing kayaks using carbon and kevlar
woven together. This fabric is even showing up in some boats made in
North America. As you can guess the fabric takes advantage of properties
from both materials creating a lighter weight kayak that is quite stiff
although not quite as strong as the same kayak in a fiberglass lay-up.
What is the Diolene material used in many of the British
Diolene is a polyester fabric with higher impact
and tear strength than fiberglass cloth. When sandwiched with fiberglass
materials, it produces a slightly tougher kayak for the same cost as
If I wax my kayak, will it be faster in the
Surprisingly, wax on the hull disturbs the
laminar flow of the water molecules as they move past the hull slowing
the kayak. This is not something you would really notice but if you plan
on racing, don't do it. Most automotive and boat waxes do offer a
certain amount of UV protection so waxing the deck will make it look
nice and give it some protection from the sun.
What do I
need to do to care for my kayak?
Rinse your kayak often
with fresh water- especially any skeg or rudder cables and fittings.
Salt build-up on the cables is one of the major causes of failure for
both. Leave the hatch covers off during storage. If they are rubber like
the hatches on the British kayaks, treat them with 303 protectant as
often as you can force yourself to in order to keep them from drying out
and cracking. Look for 303 protectant in any good kayak or marine shop.
Can I store my kayak outside?
You can store
your kayak outside but it would be best if you kept it covered with a
loose tarp to keep the sun off of it and remove the hatch covers to
prevent excessive temperature extremes inside. Do not let your
fiberglass kayak sit in the back yard full of rainwater. Fiberglass is
porous and will absorb water adding substantial weight to the boat
Should I care if the kayak I buy has
fiberglass or foam bulkheads?
In my 10+ years of kayak
repair experience, I have found that foam bulkheads often begin leaking
within a few years. This is due to the fact that the foam shrinks with
age and pulls away from the adhesive used to seal the edges. These leaks
are annoyingly persistent even after re-caulking and I often had to
replace the foam bulkheads with fiberglass bulkheads at great expense.
What else should I look for in a new kayak purchase?
Check to see how the deck and hull were seamed together in
fiberglass and kevlar kayaks. Some manufacturers use seam tape and resin
on the inside and the outside providing a mechanical bond to both sides.
Others use a plastic narrow H-shaped moulding with a fiberglass tape on
the inside. The plastic moulding only aligns the two parts and offers no
mechanical bond of its own. This method results in only a mechanical
bond on the inside only which is not as strong as fiberglass seams
inside and out.
If the kayak is to be used on the open sea or
large bodies of water, we recommend at least two hatches and bulkheads
(fore and aft) that are nearly watertight or 100% watertight. Most
experienced kayak instructors will admit that performing a T-rescue or
other rescue of a swamped kayak with float bags as a replacement for a
hatch and bulkhead can be problematic and extremely difficult in rough
conditions. The use of a sea sock to keep the water out of the cockpit
has often proved problematic as well. A boat with leaky hatches can
quickly become a bear to empty when the %&@ hits the fan as well.
Push on the deck to see how flexible it is. It should feel pretty
robust. We have often seen lightweight kayaks from the US and Canada
that damaged quite easily when performing a simple T-rescue in flat
Kayak design is an extremely lengthy subject that could be
debated endlessly. Our best advise is try before you buy and if possible
try the kayak in conditions you are likely to be paddling in. It would
be good to discover how the boat performs in wind and waves. Some kayaks
perform well in flat seas but are an absolute nightmare in following
seas! If you are a new paddler, you may not have developed the skills to
paddle in these conditions yet and will have to rely on the
recommendations of others. Just remember, most paddlers that have
recently spent thousands of dollars on their kayak will be hard pressed
to say anything bad about their kayak out of pride and a need to feel
they themselves made a good purchase.
Above all else, buy a boat
that fits you and your style of paddling!
Each model is built for
a range of paddler sizes. If you feel like you are sloshing around in
the cockpit, you will have poor control of the boat with your lower
body. Since your contact with the kayak is with your feet, thighs or
knees, hips and butt, this will seriously inhibit performance of your
boat with you in it! If you expect to be paddling regularly with a group
of kayakers that all have long, sleek (17-19') kayaks, that 14 footer
that is on sale at your local kayak shop could prove to be a big mistake
since it will undoubtedly be considerably slower. On the other hand,
don't be coerced into buying a great big expedition boat for a trip that
you might do someday if 95% of your paddling is day tripping. You can
always rent or borrow a bigger kayak if you ever have the need.