Join Date: Mar 2006
Location: New England
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Umm... the "no survey/no sea trial" part of the ad is a huge warning flag. Ferrocement boats, properly constructed, can be very good boats. Unfortunately, many ferrocement boats weren't made in anything close to the proper way, and the insurance industry and financing industry have strong reservations about giving insurance coverage or financing on them for those reasons.
Ferrocement was a fairly low-cost way to make a very sturdy boat. Many used pipe instead of solid rod for parts of the framing, and that is a serious problem, since the pipe would allow condensation to collect inside it, and then corrode from the inside out... weakening the frame and construction of the ferrocement boat from deep inside, where it would be very difficult to detect.
The idea of ferrocement construction was to bind many (eight or more usually) layers of steel mesh together very tightly. Then cement was forced into the mesh and over the mesh to form the hull. If the mesh was not bound tightly enough together or the cement not packed in properly, you would get either areas of fairly thick cement layup or voids in the cement layup—either of which would seriously weaken it. In theory, the construction was much like that of fiberglass boats... you had the steel mesh acting as the fibers, and the cement acting as the resin, and like a fiberglass boat, the strongest layups had the highest concentration of mesh and relatively low concentrations of "resin".
Another area where the construction techniques often fell short was in the "curing" phase of the ferrocement boat. The hull, once plastered with cement, needed to be kept wet, to allow the cement to harden with maximum strength. If they failed to do this... it would visually appear the same, but the strength of the hull would be vastly lower that it could have been. On one boat I know of the hull had a few spots that were apparently "missed" it the wetting out process and that is where large cracks developed in the boat.
I've seen some really beautifully constructed ferrocement boats... which were hard to tell as ferrocement boats. These are pretty far and few between. One of the sailing magazines had a good article recently on ferro-cement construction which you might want to read. If I can find the article, I'll post the name and date of the magazine.
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You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.
—Cpt. Mal Reynolds, Serenity (edited)
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Still—DON'T READ THAT POST AGAIN.
Last edited by sailingdog; 12-07-2007 at 12:37 AM.