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Old 01-06-2004
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Cored or NOT cored?????

Sorry, I missed the other items in this thread. For Jack, in using the term "non-directional cut fiber reinforcing", I meant both mat and chopper gun applied laminates. I have mentioned before the research project performed at the U.S. Naval Academy on fiberglss composites, and in particular the component that addressed impact resistance. One of the most significant findings in the course of the study of impact and impact resistance in FRP was that non-directional fabrics (in the NA study they used mat) dramatically decreased the impact resistance of the laminate and served at the failure zones in almost all cases. Other earlier studies found similar results in studying fatique in FRP.

The bad news is that virtually all boat builders use some amount of non-directional fabrics. In the best cases it is only present in the form of a ''veil coat'' below the gelcoat to minimize print through. Most production hand laid up boats still use mat as a ''bridge laminate'' to level out and bridge between the uneven surface layers of roving. One of the reasons that older 1960''s and 1970''s era laminates were found to be more brittle and fatigue prone than modern laminates is that very large percentages of the layup which were non-directional materials, generally in the form of mat.

As to the Laser 28, I really loved my boat, but I felt that it required a little more skill to handle than a more heavily ballasted and perhaps lower SA/D boat might have required. We generally cruised with a 105% lapper which was a great sail, easy to tack and quite versatile in winds from maybe 3 knots to up to 20 knots. I kept my boat rigged for both a single and double reef lead back to the cockpit (two line reefing)and when cruising would typically at least use the single reef as winds approached teh high teens or so. Over 20 knots the boat was most happy with small 90% blade and eventually a second reef.

The boat gave you a lot of tools to deal with changing conditions, all from the cockpit and most from the helm. The boat would hove to under bare poles and generally under sail as well although oddly enough there were times when I could not get her to stay hoved to (but I also occasionally encountered that same thing with the 1939 full keeled Stadel cutter that I owned in the 1970''s). All of that said, in hindsight I think that the boat required a certain level of athleticism. My father and stepmother recently sailed with me on my current boat, (He''s 76 or 77 or so also and in very good shape). We were thrashing to windward in gusts in the mid-twenty knots range and a pretty steep chop. The boat and I were loving life.

After a while my father volunteered that "He and Betty (my stepmother) generally do not experience that kind of vigorous sail very often." When I stopped and thought about it it was a pretty good work out to drive into a chop at the speeds we were moving. I think that I tend not to be all that aware of the amount of sail trimming and effort that I expend pushing a boat. It is only when someone else comes along and comments that I realize that I am playing things as much as I do. I don''t know how else to explain my comment that these are pretty athletic boats to sail.

Regards
Jeff
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