Builders' Forum Archives
Re: Stupid question.....
Posted by LeeG on Mar 28, 2005
not stupid at all. 1/8" hole doesn't provide enough exchange of air to dry out the compartment. Air has water vapor in it. When the kayak is taken into a place that's colder than the air in the compartment it'll condense on the sides. When you go into high humidity environments (with a kayak?) that air gets brought into the compartment when it's set into cold water. So you could have water vapor laden air brought in through that 1/8" hole every time you take the warm kayak sitting on the roof rack and put it on the water. Take the kayak home and that air doesn't exchange enough to dry out. One day you take the kayak out into a 90 degree day and the inside of the compartment heats up to 120degrees,,with steamy, steamy water vapor behind it. That water vapor will find the teeny, tiny hole you missed up under the sheerclamp and get steamed into the soft absorbant okoume. Tada! black ick is all yours,,unless you paint the hull and deck so who cares, you won't see it. On this friends ch17 the wood is darker on either side of the bulkheads,,and that's WITH hatches and bulkheads kept on. The few ozs of water in either compartment gets steamed up in the heat and goes right through all those tiny gaps in the epoxy not got with one THICK layer of epoxy. I made a small kayak that didn't have hatches and bulkheads but had about two good seal coats over the glass. Float bags were left in it. Not until i moved to a hot humid envirnoment did I start noticing fogging of the epoxy and black ick showing through the varnish as the float bags kept a little water trapped between the nylon bag and well sealed wood. In direct sunlight and closed compartments where water vapor can't release things start stewing. Structurally it'll never be problem,,but if you're putting down five coats of varnish it's probably for a reason,,otherwise exterior latex house paint works fine for finishing.
In Response to: Stupid question..... by George K on Mar 28, 2005