Home |
Search |
Today's Posts |
#1
![]()
posted to rec.boats.cruising
|
|||
|
|||
![]() Fact: It takes a pressure gradient on a membrane in order for osmosis to occur. Fact: A blistered bottom is the result of untold hours of this pressure gradient. Sometimes it takes years of submersion which creates the pressure gradient for blisters to occur. Osmosis is a relatively slow process when pressure differentials on either side of a membrane are not great. Fact: Spraying the blistered bottom repeatedly with fresh water does NOT create osmosis as there is no pressure gradient. Fact: No pressure gradient = no osmosis = surface wetness only = no penetration into soggy laminate. Fact: No penetration = wishful thinking and NO effect upon reducing the moisture in the soggy laminate that combines with layup chemicals. Now, to the crux of the matter which is how to remove the moisture from the laminate before coating the bottom with an impermeable 'barrier coat.' There is only one way to accomplish this drying process and that is not by osmosis but by diffusion through the membrane and evaporation of the moisture at the surface of the membrane. This process involves storing the soggy layup in a low-humidity environment for a year or two so diffusion and evaporation can occur and the hull can be tested with a moisture meter until it reaches acceptable levels. I welcome any rational, enlightened explanation of how spraying the hull with water can possibly negate or supersede the above facts. Wilbur Hubbard |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
A case of identifying Osmosis | Boat Building | |||
Osmosis on topsides | Cruising | |||
Osmosis blisters ? | Cruising | |||
Portable Reverse Osmosis | General | |||
Source for Reverse Osmosis (RO) Membranes | Cruising |