Conference unifix::sailing

	I was taking a close look at a COMPAC 27 while it was on shore.
I was taking a close look and found 4 'platic' thru hull fittings below
the water line in the stern.  2 were larger and 2 smaller.  The point is
that the smaller ones look different.  They were because the shank had been
broken off, and you could see the hull.  This meant that the edge of the
fiberglass hull was in direct contact with the water!!.  I figured that
the installer had used the same tension on all of them and the smaller
broke!!.  This was a 'new' boat in the dealer's yard that they had sailed
from Blue Hill bay to Portland Me. for a boat show and more.  I figure
that if in a couple of years, if they still hadn't sold it, I'd might make
them an offer as a used boat contigent on a survey, especially of the
engine installation.  I'd replace those thru hull fittings with bronze
before I'd even take a ride in that sucker!!

	Dave

see note 273

    Why not plastic seacocks? the rest of the boat is plastic!
    
    :-) 
    
    "If God meant us to have plastic boats he/she would have planted
    plastic trees"

re .3:

Carrying your logic one step further would dictate that wooden boats 
should have wooden seacocks. There ain't no bronze trees either!

    I was the one who originally entered in note 273. I eventually did
    install Marelon (Mare as in Sea, and Lon for Nylon) seacocks and
    through hulls. Marelon material is a glass filled nylon composite,
    that has the following advantages;
    
      Inexpensive
      Good Strength to weight ratio
      
    They have the following disadvantages;
    
      Poor High Temp performance
      UV sensitivity, unless they are filled with a UV Blocker
      Less Strength than Bronze.
    
    So it all depends on your application. If we are talking about
    installing them on a 'blue water' cruiser go first class and buy
    bronze. If we are talking about a 25' coastal cruiser like mine, go
    with Marelon, since the Marelon will hold up as well as the rest
    of the boat.
    
    As Ed said don't use them on any hot water line, Nylon is not meant
    to take high heat for an extended period of time (but you can boil
    them with no problem - the problem is that at boiling they will
    plastically deform under load).
    
    The important thing is to mount them properly with adequate backing
    plates, and in a location where they won't get hit if you ground or run
    into the dock. You might also think about having only one water inlet,
    and mount the outlet above/or at the waterline. This would limit your
    liability if something would ever fail (the fewer holes below the
    waterline the better). 
    
    To sum it all up, your application is the key.
    
    /jim 

    I went into Boat US and selected a 1 1/2 Marelon valve and took
    it to the counter.  The rep promply told me he had used them, but
    replaced them after one had split wide open.  I looked at the valve
    and noticed it had no drain hole and figured that could be a reason
    for it to split in freezing water.
    
    I put back the Marelon.
    
    I had the boat hauled Wednesday and stayed with bronze.  That was
    the good choice;  the bad choice was the day for the haul and the
    eight mile sail in 27 degrees and 30 knots of NW wind.  It is usually
    spring by now in the Chesapeake.