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-   -   Trivial question about entagled lines. (https://www.boatbanter.com/cruising/95362-trivial-question-about-entagled-lines.html)

[email protected] June 16th 08 03:29 PM

Trivial question about entagled lines.
 
This is a trivial question, but it drives me crazy, and maybe somebody
can help me.
For my dinghy/davit system I have 4 triple blocks – two for each side.
All of them are for 3/8 line. Now here is the problem:
Every time when I put the dinghy down and again back the line is
twisted and become entangled. Every time I have to spend time to fix
it – and really drive me crazy.
I use polyester yacht braid.
Thanks in advance
Mada

[email protected] June 16th 08 04:37 PM

Trivial question about entagled lines.
 
On Jun 16, 4:29 am, wrote:
....
Every time when I put the dinghy down and again back the line is
twisted and become entangled. ...


Hmmm. I don't know, but have you tried coiling your line into your
other hand? I suspect you're twisting the line as you coil it. You
could test this by throwing the tails out on the deck and running your
hands down them to take out the twists and then using the davits. If
you're problem gets much better or goes away then the coiling is your
problem. If not, beats me...

--Tom.


[email protected] June 16th 08 06:09 PM

Trivial question about entagled lines.
 
On Jun 16, 11:55 am, "Roger Long" wrote:
It's hardly a trivial question. Getting the twist out of lines so that they
don't do this when a load is put on is hard. The snags can hurt you or your
boat if they occur somewhere more critical. Suppose the dinghy was your
only way to reach someone in the water because other devices had drifted
away from them?

If you just take the line as it came from the store and run it through the
blocks this will probably happen.

First, learn to coil properly. Take the new line and start coiling it up, a
real coil, hanging from one hand and measuring with the other; not winding
around thumb and elbow the way all former girl scouts seem to do. Twist the
rope between thumb and forefinger so that each loop hangs exactly parallel
and easy with the one before it. With new line, you'll find that the twists
build up so you have to stop periodically and whip the uncoiled part around
and around in the other direction to work the twist out. Don't accept any
tendency for the loops to look like they are trying to go into a figure
eight. You may have to go through this process a few times.

For lines as short as davit falls, you might also hoist the line up the mast
with a halyard and work the twist out. I've heard that towing them astern
for a while works wonders but I've never done it.

You'll probably still have some tendency to twist under load even after all
this. It sounds like you have swivel blocks on your davits. There is
really no need for them to swivel in this applications. Replace them with
non swivel blocks or put a siezing of wire or marlin around the block and
shackle so they can't turn.

Another thing that can easily happen with something like dinghy davits is
for the block to get turned over when disconnected. It can be a maddening
mental exercise to figure out which way it should go back if it twists
through the parts. Try hooking the two blocks directly together after
disconnecting the dinghy. This will also help keep them from swinging
around.

--
Roger Long


Don't you have to reverse the twist for every other loop, or you are
creating twists in the line ? I just do a figure 8 loop instead.

Todd

Ernest Scribbler June 16th 08 06:39 PM

Trivial question about entagled lines.
 
wrote
Don't you have to reverse the twist for every other loop, or you are
creating twists in the line ? I just do a figure 8 loop instead.


I think Roger's talking about untwisting the tail of the rope as he coils. A
problem I've seen with the over and under technique (which I think is what
you mean) is that it's really easy to produce a long string of evenly spaced
knots when uncoiling it.



Ansley W. Sawyer June 16th 08 06:46 PM

Trivial question about entagled lines.
 
Mada,

One other thought.

The falls of my davits become more twisted if I leave a half turn around the
cleat as I lower. I always used to do this as it took some of the weight but
now I take the line all of the way off the cleat before lowering.

Ansley Sawyer
SV Pacem



Edgar June 16th 08 06:59 PM

Trivial question about entagled lines.
 

wrote in message
...
This is a trivial question, but it drives me crazy, and maybe somebody
can help me.
For my dinghy/davit system I have 4 triple blocks – two for each side.
All of them are for 3/8 line. Now here is the problem:
Every time when I put the dinghy down and again back the line is
twisted and become entangled. Every time I have to spend time to fix
it – and really drive me crazy.
I use polyester yacht braid.
Thanks in advance
Mada

I suspect it hs something to do with the way you have reeved (roven?)the
line through the blocks as braidline itself has no tendency to twist under
load.
Two triple blocks on each hoist sounds excessive. However if you use these
you have to fix the end of the rope at the top and reeve the line so that
the fall emerges from the centre sheave of the top block This prevents any
tendency for the pull on the fall to twist the whole assembly and for the
same reason said fall must finally emerge also from the centre sheave of the
bottom block If you do not reeve this system correctly the bottom block will
tend to turn over while you are hauling in the slack after launching the
dinghy and I suspect that this is the root of your problem.

It is more usual for boat hoists to have a triple block at the top and a
double block at the bottom since the fall must always emerge from the top
block. Therefore the double block at the lower end has a becket on it onto
which the other end of the rope is spliced and you must then reeve the rope
so that it emerges finally from the centre sheave on the top block, You do
not need swivels on the blocks for a dinghy hoist and if you have swivels
that may also be part of your problem




[email protected] June 16th 08 07:58 PM

Trivial question about entagled lines.
 
On Jun 16, 1:39 pm, "Ernest Scribbler"
wrote:
wrote

Don't you have to reverse the twist for every other loop, or you are
creating twists in the line ? I just do a figure 8 loop instead.


I think Roger's talking about untwisting the tail of the rope as he coils. A
problem I've seen with the over and under technique (which I think is what
you mean) is that it's really easy to produce a long string of evenly spaced
knots when uncoiling it.


I think you are right there (which is why I like the figure 8 coil),
but the very act of:

"Twist the
rope between thumb and forefinger so that each loop hangs exactly
parallel
and easy with the one before it. "

Creates a half twist in the rope for each coil. If you make alternate
twists in opposite directions (see http://www.animatedknots.com/coiling/
) then there is no twist built up in the rope while you coil it.

Todd

[email protected] June 16th 08 07:58 PM

Trivial question about entagled lines.
 

Call me old fashioned but I like the look of a regular coil. I've never
tried the figure 8 method or even seen it done so I don't know if it work
for a hanging coil.


--
Roger Long





[email protected] June 16th 08 08:01 PM

Trivial question about entagled lines.
 

Call me old fashioned but I like the look of a regular coil. I've never
tried the figure 8 method or even seen it done so I don't know if it work
for a hanging coil.

--
Roger Long


You're old fashioned :-)

Looks aside it works very well and hangs just like a regular coil.
And it does have a better chance of running free after being dropped
off the cleat than the round coil.

I climbed rocks before I sailed much, but learned the figure 8 from
sailors.

Todd


Wayne.B June 16th 08 10:18 PM

Trivial question about entagled lines.
 
On Mon, 16 Jun 2008 11:55:49 -0400, "Roger Long"
wrote:

Don't accept any
tendency for the loops to look like they are trying to go into a figure
eight. You may have to go through this process a few times.


Not sure I agree with that advice. Coiling as a "figure 8" totally
eliminates any tendency fo the line to twist or kink. It is one of
those time honored traditions of the sea called "faking" or "flaking"
the line, and is used for those situations where a long run of line
absolutely has to run out quickly and cleanly. Racing sailors
routinely do this with spinnaker halyards on big boats to ensure that
the takedown goes quickly and smoothly.


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