Thread: rigging wire
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Richard Casady Richard Casady is offline
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Default rigging wire

On Thu, 12 Feb 2009 21:44:06 +0700, Bruce
wrote:

On Thu, 12 Feb 2009 09:39:58 +0000, IanM
wrote:

Richard Casady wrote:
On Tue, 10 Feb 2009 13:35:15 +0700, Bruce
wrote:

The first problem comes when you attempt to locate proper heavy duty
thimbles for the eyes. Damned hard to find. Next comes splicing the
eyes in the cables. Again, if you can do it yourself and have the
tools then go for it but if you are paying rigger's rates then get
your wallet ready.

Don't they have fittings that avoid the eyesplice, for stainless, but
not for galvanized? That would do it even if stainless is six times as
costly. I don't know about those compression sleeves. I remember in
the fifties when Lands End sold nothing but sailboat stuff. They had
sleeves and a tool that looked like a boltcutter.


No, I was referring specifically to thimbles used in eye splices as I
assumed that if one were complaining about costs one wouldn't want to
buy swedge fittings as a non-stainless swedge fitting any where that
it gets salt water on it probably has a shorter life then a properly
made and served eye splice.


Poured socket terminals were the 'gold standard' for wire rope terminals
for the greater part of the last century. The end of the rope is
splayed in a controlled fashion and spelter (usually zinc alloy) is
poured in to the terminal to form a solid wedge retaining the rope.
Used to be the Navy standard for all wire terminals used for safety
critical lifting. Works for galvanized and bare steel wire but I believe
its not so good for stainless as the spelter doesn't wet the strands
properly.
Check out chapter 10 of:
http://www.fastlift.co.za/pdf/CASAR%20-%20Wire%20rope%20end%20connections.pdf


Called "spelter sockets". There is a boat builder in Phuket that has
proper bronze fittings cast and uses them from time to time. They used
to be common around cranes but have largely been replaced by wedge
sockets as the poured sockets take a bit of skill to make. Or perhaps
more accurately, a bit of attention paid to the proper technique.

for instructions. It should be noted that unlike most other terminal
systems, it does not de-rate the wire strength from 100%



I think you'll find that sta-lock type of fitting will test stronger
then the cable. One test was 107% of rated cable strength.

The tools and materials to do it are affordable and can be carried on
board nearly any boat, the terminals are generally reusable and the
galvanic compatibility is good, but you do need to be ashore or in a
very sheltered location to work with molten spelter so some screw down
compression fittings of any of the types suitable for galvanised wire
would need to be stocked for any repairs under way.


The spelter is just zinc in most cases.

You can get 3/8 galv. for less than a buck a foot, breaking strength
14 000 lbs. My original reference was to anchor rode, and you can bet
the ranch it wasn't stainless. You can brush grease over a wire filled
winch drum and not get it on the rest of the boat.

People who aren't useing it say it rusts. How come the zinc does not
afford anodic protection to the steel. I drive by the neighors steel
roof that has a third of the zinc gone, and no rust. No salt of
course. My dad built the Iowa schooner [only been the one] and used
galvanized. Whatever the local hardware store had.


Your neighbor's roof wasn't immersed in salt water very often either.
I doubt very much if galvanized wire will make a satisfactory anchor
rode as I can't see how you can wash all the salt out of the stands
so it will be rusting quietly away while on the drum.


The galvanized will have more of a rust problem than the plain steel
the tugs use, you say. I don't think so.

Casady