Re: Where to buy screw/helical anchor/mooring?
ok, as luck would have it, my neighbor informed me that the previous owner had already installed a helical anchor, but that it was now lost on the bottom somewhere. well, at low tide i shuffled through the water until i found it. so now my problem will be to attach the boat to it (it's deeply embedded, and the eye seems solid--i'll take a better look this weekend). looks like i'm going to need 1) a heavy chain attached to the mooring of about 10' (1.5x water depth) 2) a light chain of 6' or so, 3) a buoy, and 4) some heavy duty nylon rope 2.5x my freeboard. questions:
1) how heavy, exactly, should the heavy chain be? i see "as big as you can", but a more solid # would be nice. this boat will be moored on the potomac, which is generally fairly serene but can get rough. i'm only leaving it in the water when i'm there, so i should know if something real severe is on its way in.
2) how do i attach the pennant to the mooring, and to my boat? as in, what knots/securing devices should form the loops in either end of the rope? looks like i can use some nylon-reinforced pvc for a chafe guard to attach to the chain shackle, and presumably to the chain hook/clip or whatever that i attach to the bow eye.
as for the mooring system, here's the info i was looking for on the helical anchors:
"Helical Piles or sea screws are not common,
but are exceptionally effective. These are long
shafts of high tensile steel with an attachment eye
at the top and large threads at the lower end.
These ?screw anchors? are screwed into the bottom.
Common lengths are 8? with threads of 10? to 14?
in diameter. When embedded into the bottom with
the top eye flush or into the bottom soil attached
to traditional ground tackle, their holding power is
exceptional. Recent tests have shown that their
holding power is vastly greater than any traditional
mooring system of mushroom or deadweight
anchors. These anchors have been used by the
offshore oil industry for more than 20 years and
are quickly appearing in the yachting market."
here's the source
http://www.inamarmarine.com/pdf/Moorings.pdf
very useful info on moorings.