Comparatively lighter hulls mean more manoeuvrability, easy
launching and retrieving, and greater access to shallower waters.
They can also carry immense weight compared to fibreglass hulls.
up to 35 000psi before deforming, compared to steel which cracks
or breaks at 45 000psi), durable, low maintenance and rust free, and
similar to motor vehicles, they can be “panel beat” and re-welded if
involved in accidents. Aluminium too is non-sparking, so fire risk
with petrol etc is vastly reduced.
My investigations highlighted a few negatives with aluminium
boat construction worth noting. Some cheaper manufacturing
processes use pop-rivets and glue instead of welds in the main
manufacturing process and this can lead to hulls developing leaks
and even “coming apart” under stress. Even on welded craft, some
internal non-structural components - such as the floor - may be rivetted
in place. Aliboats weld their hulls, using high quality stainless steel
pop-rivets (or weld the floor if designed as a wet-deck). Aluminium
skin thickness is another big factor, and this will vary from company
to company and has noticeable impacts on prices, as does the use by
some of non marine-grade aluminium. It is generally accepted that
5mm aluminium plate is better and more long lasting than the 3mm
plate sometimes used in hull construction. While there are deep vee
hull designs (better suited to rough water), many aluminium hulls
follow a more flat-bottomed profile, and while incredibly stable, can
be uncomfortable in the rough. Aluminium also tends to amplify
noise (of the hull moving through the water, or internal noise being
transmitted to the water) unless carpeted. Some designs have exposed
structural ribs or braces (usually smaller craft) which can make them
uncomfortable - stubbing toes, catching on skin and clothing in rough
water etc.
While the aluminium boats offer no advantage in the hull purchase
price, they have plenty of pluses once purchased. In most cases,
fibreglass and aluminium will work out about the same, with possibly
the aluminium being more expensive, but that is where the savings
start. Aluminium boats of the same dimensions as a fibreglass boat
will require up to 40% less horsepower to attain the same performance
(this is subjected to how you load each, but is a guide). There are many
prime waters throughout southern Africa which have horsepower
limits for boats, usually governed by conservation issues, and where
aluminium really comes into its own.
Simply, the complete aluminium rig on a trailer may cost out
cheaper than a fibreglass boat. Ultimately, this can equate to less fuel
and oil usages and lower engine maintenance costs. The comparatively
lighter hulls mean more manoeuvrability, easy launch and retrieve, and
greater access to shallower waters. Because of their initial lightweight
too, they can carry immense weight compared to fibreglass hulls.
Used by many safari operators, aluminium boats are often left in the
water for years at a time - something which cannot easily be done with
fibreglass due to osmosis - the process of absorbing water through the
P a g e 12
fibreglass. Floatation is normally provided by (under floor) polystyrene
or sealed bottles depending on applicable regulations in the country
of use. In the longer term - due to their longevity - aluminium boats
retain a much higher re-sale value compared to fibreglass.
Probably one of the biggest advantages to the aluminium option,
is that you almost get to design your own interior. There are certain
structural braces which need to be incorporated (in smaller boats,
these will take the form of bench seats etc), but so long as you can
work around that, and depending on how much you want to spend...
the sky is the limit. Now that really appeals to me. Fuel tanks, live
well, storage hatches, consols... you name it, it can all be designed to
meet your specific needs. Van Louverdis, sales manager of Aliboats
confirms this saying “The interior of our boats can be tailor-made to
the client’s specifications from our list of accessories - there are very
few restrictions as to what we can do to fulfil the customers needs.”
Interestingly, their hull designs originate from a naval architect based
in the USA, and are computer formed at the factory in Botswana.
Reputable companies like Aliboats in Maun will also back this
durable material up with some serious guarantees. Says Van “Our
boats last a lifetime and come with a 10 year ‘hull’ guarantee against
any factory defects.” They have a large selection of hulls to choose
from, both for salt and fresh water applications. Van explains “Some
of the boats we manufacture include rugged ‘working boats’, such as
our hugely successful