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Re: Floatation
By:Paul G. Jacobson
Date: 7/22/1999, 12:24 pm
In Response To: Floatation (Jim Eisenmenger)

> Does a strip built boat with no built in floatation remain afloat when
> capsized, or does the fiberglass and epoxy counteract the bouyancy of the
> wood?

> I am aware of the need for floatation as a safety measure in wet exits and
> re-entries, but I would like to paddle a little before taking the time to
> fully complete my boat and don't want to lose it if I capsize.

Even if it is completely filled with water an EMPTY strip built boat will float. The wood is more bouyant than the water, and the addition of the fiberglass and resin does not significantly reduce that bouyancy.

However, what are the odds that your boat will be complety empty when it submerges?

You want to add suficient additional flotation through sealed air chamers or foam or float bags to offset the wet displacement of your gear. That is not necessarily the *weight* of your gear. For example, If I carry a cast iron Dutch oven for cooking while camping, and it weighs 12 pounds, with the lid, but I pack it in it's own watertight and airtight bag that displaces 15 pounds ( a volume of about 2 gallons or 8 liters or 8 quarts) then its wet displacement is positive. It will float if it is submerged and it will actually add to the flotation of the craft. On the other hand, if I just throw that Dutch oven into the boat, then its wet displacement is going ot be negative, and it will require me to add additional flotation .

One of the points you may gather from the above example is that the flotation of the well sealed packages of gear can be a replacement for permanent, built in flotation. I like to pack my gear so that each bag can float. That means mixing some very heavy items with the very lightest, or packing them in sealed, waterproof bags with a lot of trapped, additional air.

hope this helps.

Paul G. Jacobson

Messages In This Thread

Floatation
Jim Eisenmenger -- 7/22/1999, 12:03 pm
Re: Floatation
Hank -- 7/23/1999, 10:07 am
Cheap, temporary flotation
Pete Roszyk -- 7/22/1999, 6:26 pm
Re: Cheap, temporary flotation
Don Beale -- 7/23/1999, 11:28 am
Re: Floatation
Paul G. Jacobson -- 7/22/1999, 12:24 pm