Re: P19 dgrbrd (daggerboard) cable tension and trailering...

theodore f. boyer (freelanc@execpc.com)
Thu, 22 Apr 1999 23:22:38 -0500


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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Hi All,
We will all have wire rope (cable)/sheave problems, because all wire rope
under load naturally tends to flatten out. The design consideration has to
include the sheave groove design (pulleys) to match that normally flatting
condition, which also includes the material composition of the sheave. You
will note that Harken uses two different material colors in their sheaves. For
example: In our dingy class items, the gray color sheaves in the blocks are
for wire rope (cable), while the black color is for lines (generic term -
rope). If this is not watched in ordering and assembly, you can expect
disaster. The same applies for large shovels and draglines.
Ted- Milwaukee WWPotter19, Hull#0940 "Sea Breeze"

Gordon wrote:

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> West Wight Potter Website at URL
> http://www.lesbois.com/wwpotter/
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> I'm getting the impression that P19s all came equipped with rope-type
> sheaves instead of cable sheaves for their winch cables. Why would HMS or
> IM do that?
>
> Harry Gordon
> P14 #234, Manatee
> Mountain View, CA
>
> >Gang,
> >
> >My keel cable is ruined, some blocks are ruined as they
> >aren't the proper kind for wire, and one block has been
> >cut 2/3rd's thru when the wire slipped off the sheve.
> >
> >I was told by a gent who claims to have owned 12 sailboats
> >that the problem is STAINLESS STEEL cable, which flattens
> >and then does NOT re-twist. He recommends plain steel
> >cable, or for a WWP15 or 19 1/4" Yale Lite (2500# breaking
> >strength) which will stretch some initially (but since
> >your keel should not be left hanging will only be under
> >stress for minutes). He claims he has done this and I am
> >going to try it. As soon as I can find time, I am
> >installing double blocks at the keel and above, which will
> >reduce the load accordingly. Should also make it easier
> >to raise and lower keel. I'll let everyone know how it
> >operates.
> >
> >Ted Duke
> >WWPs19 #626
> >Rainy, chilly Mountains of Virginia
> >Why doe's the sun only shine when I'm out of town?