Upgrading Flotation and Equipment Flotation Modifications
Snipe rules (Rule 15 in the SCIRA Official Rulebook, 2005-2008
Edition) call for hull floatation provisions which can be accomplished
by using watertight bulkheads in the forward and aft portions
of the hull, an underfloor watertight chamber, low density closed
cell foam, floatation (buoyancy) bags, or a self-bailing cockpit.
A combination of these features also may be used providing the
floatation requirements are met. Foam floatation is most effective
if installed on the bottom and sides of the hull, rather than
under the deck.
As photos become available, floatation provisions installed by
owners of wooden (planked and plywood) Snipes will be shown as
examples how these modifications were accomplished. Click images
to enlarge.
 Forward sealed plywood bulkhead (1/4 in. or 6mm) added to Varalyay
wood Snipe #14177. Mast step is aft of bulkhead. Deck beam system
has been modernized as shown in "Building A Plywood Snipe" (available
from SCIRA). Bulkhead and other joints are glued and reinforced
with epoxy adhesive and filleting mixture. Note that deck must
be removed to accomplish bulkhead installation.
Forward sealed bulkhead on Snipe #14177, viewed from aft side. Note location of bulkhead relative to hull frame and mast step
on keel. Deck framing at top of bulkhead used to attach top of
bulkhead and decking (to be added), and forward end of mast hole
and associated framing. Note also lowered daggerboard trunk and
brace/stiffener to deck framing at forward end of trunk. A temporary
brace has been installed to maintain hull shape until side deck
framing is installed. When installing this type of floatation
system, forestay and jib downhaul hardware and rigging should
be installed before installing the deck, since access to the space
forward of the bulkhead will not be possible. It is advisable
to install one or two watertight access ports in the bulkhead
to provide ventilation during storage, and to allow for periodic
inspection for any trapped water forward of the bulkhead.
 Aft sealed plywood bulkhead (1/4 in. or 6mm) installed at back
end of cockpit on Snipe #14177. Deck framing system as shown in "Building
A Plywood Snipe." Side decks in cockpit area not yet installed.
When installing this type of floatation system, rudder gudgeons
and decking reinforcement (blocking) for the mainsheet traveller
system and associated hardware and rigging should be installed
before installing the deck, since access to the space aft of the
bulkhead will not be possible. It is advisable to install one
or two watertight access ports in the bulkhead to provide ventilation
during storage, and to allow for periodic inspection for any trapped
water aft of the bulkhead.
 Transom drain holes can be added to facilitate draining of trapped
water in the hull in the event of a capsize. The maximum total
area of drain holes is 100 sq. in. (for example, two holes 5 in.
x 10 in. each), per the Snipe rules. They would work best when
buoyancy (floatation) bags are also installed in the bow, sides
and stern, and in combination with a cockpit bailer installed
in the bottom in the cockpit. This installation is on wood Snipe
#6940, built in 1947 and later updated. When cutting holes in
a planked transom as shown, it is advisable to reinforce around
the perimeter holes, on the interior side of the transom, with
1/4 in. (6mm) exterior plywood backing epoxy-glued to the planks
to prevent potential cracking or splitting of the planks. Radius
cuts are recommended at the corners of the holes to avoid stress
cracking of the planks. If the holes are cut too close to the
bottom, water may flow into the boat when launching off a trailer
or dock, or while installing the rudder and tiller. It is recommended
to keep the bottom edge of the holes above a horizontal line on
the transom extending from the chine intersection at the bottom
and sides. The shape of the holes is optional. For example, triangular
shaped holes have been used on fiberglass Snipes, with the bottom
edge of the holes sloped (parallel to the edge of the bottom planking
at the transom), and the top edge horizontal. However, the maximum
area requirement described above must be complied with.
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