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Wood or Glass?
Cold moulding is effectively using a timber laminate (like plywood) with the grain running in different directions on alternating layers and then pressure moulding it into shape. It produces a "skin" hull that makes for a good deal of rigidity as well as flex and shares many characteristics with GRP hulls.
Traditional timber hulls are made with planks (with the grain usually but not always, running along the length of the boat) over ribs. Pretty much at every point that you want the hull to change shape, you need a rib. The planks are either steam, dry heat or salt water moulded to the ribs and then secured in place. There is a lot of caulking and mystery involved between each plank (which only mostly behaves like it is part of a larger structure called a "boat").
So if you want to get a glass finish appearence on the topsides of a plank-built wooden boat, you can work very hard at it, and even get something that looks right. ...Until you put the boat back int he water and let it ride at it moorings for an hour or so. And then every plank will swell and flex a little differently, and even if the boat does not let in a drop of water, you will once again be able to see every individual plank.
Don''t get me wrong. I sail on a H28 that is lovely and wonderful...but I am glad that I do not own it! I have my Endeavour and love every solid fibreglass inch of it.
Cold molded sort of bridges the gap between the two. But personally, unless you are racing and want the super-light hulls that cold moulded timbers can generate....I would go with GRP.