Ted wrote:
>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"
I thought I could make a clean get-away this morning, but then read this
post. I am probably interpreting what is being said the wrong way, but to
clarify my earlier post about the blocks that came (come?) on the P-19 keel
raising system let me quote the West Marine catalog. The blocks that came
on my 1995 Potter were Harken 183s. These are listed as "Rope/Wire Bullet
Blocks". The description includes: "Designed for... where wire is used or
for rope where loads are too high for regular bullet blocks." Unless I am
still confused by nautical terms used by (true) sailors, this seems to say
that the blocks can be used for rope (line) or (braided) wire.
Having said this, and in light of what the Harken engineer told me, I advise
all P-19 owners that have the 183s in their boats to start saving their
pennies to purchase a couple of true wire blocks like the Harken 304 or 308.
Why doesn't IM put these in their boats? Could it be that a 183 costs
$14.18 and a 308 costs $40.59? (plus the cost of a swivel). I can't seem to
come up with any other reason.
Larry