Amost every boat needs protection from pilings, docks, mooring
cans, and other hazards that can scrape, abrade, lacerate, and
scar a boat. And small boats in particular need as much armament
as practical. Short of equipping your hull with an encircling
fender like a circus bumper car, there are any number of protective
devices from which to choose.
"Mill" plastic (Fig. 1) (editors note: the author
is probably refering to UHMW) is a dense, tough, waxy plastic
available insheets from sawmill and industrial supply houses.
It's used in areas of friction and wear in lumber mills and other
industrial applications. The whitewater dory crowd long ago discovered
it as a way to virtually bulletproof their dories from the types
of punctures encountered on rivers. They use it for chine and
bottom protection, sometimes even screwing entire sheets to the
bottom.
Mill plastic makes good reinforcement and protection for chines,
hull, and gunwale. However, it is so stiff, even in 1/4-inch thicknesses,
that it won't readily bend around a chine, so you will have to
use it in strips. If you're wearing down the keel of your boat
scraping across rocks, cut a strip of the stuff and stick it down
there. It's very slippery and won't stick to rocks like aluminum
or lead keels.
Attaching the plastic takes some thought. Mill plastic shrinks
and swells according to temperature. Attach it on a cool morning,
and by afternoon it may be full of small ripples; attach it under
a hot sun, and it may pull some fastenings out as it shrinks at
night. It can't be glued, at least not to wood or metal, so you
must rely on mechanical fastenings. And if you're using it on
a wood hull, the wood underneath must be well sealed to prevent
rot. Three coats of epoxy or a fiberglass sheathing with epoxy
provides the best underseal.
Screws, sometimes with washers or screw caps, are one way to
attach the plastic. A round head with a small washer is most effective
because it spreads the fastening force over a larger area. If
you're using it on the gunwale or hull sides, try countersinking
the fastenings to prevent damage to other boats. A flathead wood
screw will sink flush into the plastic and works well if you use
enough screws to effect a good fastening.
Another type of cushioning is roll bar padding (Fig. 2), as
seen on off-road vehicles. It's very similar to the foam tubing
used to keep pipes from freezing. Both types will work and are
soft, but it's hard to find them in anything except black; however,
we have seen it in white and gray. The black insulation may leave
marks on the topsides of other boats; wrapping it with vinyl electrical
tape will eliminate that problem. Also, unless the insulation
is made of closed-cell foam, it may absorb water. Electrical tape
can waterproof for a time, but it tends to peel. A truly waterproof
closed-cell foam is much better.
You can apply this tubing in sections to the most vulnerable
places, or you can wrap the entire perimeter of your boat with
one continuous length. If the job is done neatly, it looks good
and gives a very functional "workboat" appearance to
a small dinghy or runabout.
If you want something a little harder, PVC pipe is available
in just about any variety of sizes and some colors. A large section
split in half or thirds and screwed to a hull side or gunwale
makes a fine rubbing strip that will take unlimited abrasion,
very good for laying alongside barnacle covered, creosote pilings.
Because of its hardness, PVC pipe will protect your own boat very
well indeed, but it may not extend many courtesies to other boats.
Common garden hose can be used as a gunwale wrap ( Fig. 3) if
you don't mind the landlubberly look of the stuff. It works best
if you can seal the ends and let the entrapped air act as a cushion.
You could lash a length of hose along the outwale of your hull,
oryou can entwine it around gunwale spacer blocks. To prevent
the hose from crimping on sharp bends, cut it in sections and
thread a length of line through the sections, wrapping the whole
works around the gunwale. Position the sections of hose to provide
best protection. This cushioning is quick, cheap, and easily removable
for maintenance or replacement.
For underwater use along the hull, keel, or chine, a "hydro
cushion" (Fig. 4) works well. A piece of firehose or large
diameter garden hose will work, so long as it is flexible but
stiff enough to maintain some of its shape. The ends of the hose
should be sealed or somehow plugged; the easiest method with firehose
is to fold it back and nail the fold closed. Drill a number of
1/4-inch holes in the hose. These holes will allow you to reach
in to attach the fastenings that hold the hose in place; they
also provide the controlled circulation of water that facilitates
the cushioning effect.
When the boat is launched, the hose will fill with water; when
you collide with underwater objects, the force causes the water
to shoot out of the holes, cushioning the impact much like a shock
absorber.
Sacrificial rubbing strips (Fig. 5) on the hull are a traditional
method for providing topside protection. For hulls with extreme
tumblehome, they're almost a necessity. They can be attached to
Fiberglass, wood, and metal hulls.
The size and length of the rubbing strip is determined by the
shape of the hull and the size of strip that will easily make
the bend. It should not have to be forced into place, rather it
should bend easily without any danger of breaking.
If you don't mind sanding some gelcoat from a fiberglass hull,
or sanding down to bare wood on a wood hull, gluing the rubbing
strip in place with epoxy is a simple method. Epoxy will also
glue wood onto a well sanded and clean aluminum surface. Bolts
are used just for clamping. They are removed when the epoxy kicks,
and then the holes are filled with an epoxy mixture. When the
strip requires removal, it is simply planed off and replaced with
another.
In spite of the efficiency of the epoxy method, most glass hull
owners will choose to use bolts and bedding compound to hold the
strip in place. If you countersink and plug the heads of the bolts,
use Weldwood or resorcinol glue, for plugs glued with epoxy will
be very difficult to remove. Good bedding is important to seal
the bolt holes, and a fungicidal bedding is recommended for woods
prone to rot.
Unlike the cartoon bulldog, your boat doesn't need a collar
of spikes to protect it. Cushioning your gunwale or hull with
one of the devices described here will enable you to travel rocky
rivers or lay alongside the shiniest yacht in the harbor without
fear of damage to your boat or others.
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