http://video.google.com/videoplay?do...61924924082592

" Demonstration and comparison testing footage of plow and claw type
boat anchors vs a Rocna. Includes interview footage ... all »"

8 Minutes 20 sec ,

Mic 67

A few observations:

First I noticed a number of other patterns on the beach including a Spade
but no test results for them.
Second, beach sand reacts very different from ocean bottom. And most
important, the test were done with effectively infinite scope. Zero angle
between the rode and the beach. This works against fixed shank patterns
like the claw and the plow because it holds the shank down keeping it from
righting. Setting on a normal 4 or 5 to 1 scope the rode is angled upward
which lifts the shank and helps right the anchor. When set on a 4:1 scope
the claw type will set easier than almost any other pattern which accounts
for its popularity. It just doesn't have the holding power.

The Rocna does have good holding power and is relatively inexpensive but the
big hoop just compensates for poor balance.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Mic" wrote in message
...
http://video.google.com/videoplay?do...61924924082592

" Demonstration and comparison testing footage of plow and claw type
boat anchors vs a Rocna. Includes interview footage ... all »"

8 Minutes 20 sec ,

Mic 67

On Thu, 25 May 2006 11:00:39 -0400, "Glenn Ashmore"
wrote:

A few observations:

First I noticed a number of other patterns on the beach including a Spade
but no test results for them.
Second, beach sand reacts very different from ocean bottom. And most
important, the test were done with effectively infinite scope. Zero angle
between the rode and the beach. This works against fixed shank patterns
like the claw and the plow because it holds the shank down keeping it from
righting.

Humm...but wouldnt that apply to the Rocna too?
It would seem to and was one of my first thoughts of this test.
that is probably why an anchor with a mini float attached to it tend
or seems to be effect in keeping it in a good or better setting
position.

Setting on a normal 4 or 5 to 1 scope the rode is angled upward
which lifts the shank and helps right the anchor. When set on a 4:1 scope
the claw type will set easier than almost any other pattern which accounts
for its popularity. It just doesn't have the holding power.

Heres another link, go to the paragraph that starts "So we bought a
15# alloy SPADE which so far has done OK. ..."
"We recently learned that we were improperly setting the anchor, i.e.
we should be setting out only 3:1 scope then leave the anchor to work
down with surge. After it has been deployed for a time we can then
back down on it and/or let out more scope. "
http://goose--bumps.com/goosebumps-main.htm


The Rocna does have good holding power and is relatively inexpensive but the
big hoop just compensates for poor balance.

This seems to be addressed at
http://www.bluemoment.com/newanchors.html
"Some commentators incorrectly assume that a high tip weight is
required to push the tip into the seabed, quoting specifications such
as percentage-weight-on-tip (i.e. what percentage of the total weight
of the anchor rests on the tip when in a setting attitude)."

"However, the reality is that forces in the form of torque applied by
the rode as your boat pulls on it are far more important than the
relatively small amount of weight force present."

" “The SPADE was the best performer for a given weight. It was
roll-stable and held extremely well. It was also the most deeply
buried anchor. The Delta… and Bruce… gave about 60% of the SPADE's
hold.” This was before the Rocna was developed, and the Bügel was not
tested."


http://www.practical-sailor.com/boat.../01anchor.html
"Anchor Reset Tests
When direction is reversed 140°, a third of the anchors never broke
out, another third reset at some length, and two never reset."

"the Bulwagga anchor that challenges the Spade in every category. The
Bulwagga’s only shortcoming: It’s clumsy to handle and difficult to
stow."

I would think that the Bulwagga would be righted on the bottom every
time given it design.
http://www.noteco.com/bulwagga/multi...pdf_Jan_01.pdf

I am not advocating any particular anchor, I thought the footage of
this test maybe of interest.

I do believe that any anchors performance can be enhanced with the use
of a kellet or Anchor Catenary.

Mic67

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

I am not advocating any particular anchor, I thought the footage of
this test maybe of interest.

I do believe that any anchors performance can be enhanced with the use
of a kellet or Anchor Catenary.

Mic, please tell us something about you recent anchoring experiences,
e.g., type of boat you own, type of anchor/rode, bottom conditions,
weather, etc.

wrote:

I am not advocating any particular anchor, I thought the footage of
this test maybe of interest.


I do believe that any anchors performance can be enhanced with the use
of a kellet or Anchor Catenary.


Mic, please tell us something about you recent anchoring experiences,
e.g., type of boat you own, type of anchor/rode, bottom conditions,
weather, etc.

Knowledge is not made more true or false based upon the experience of
the person who holds it. For one thing, the person could have gotten the
knowledge from a very experienced person (as much of the links Mic posts
clearly are), for another, experience doesn't prevent anyone from being
wrong about anything, for another, theories should be judged upon their
adherence to the canons of rationality, not upon who they come from.


--
Stephen

-------

For any proposition there is always some sufficiently narrow
interpretation of its terms, such that it turns out true, and
some sufficiently wide interpretation such that it turns out
false...concept stretching will refute *any* statement, and will
leave no true statement whatsoever.
-- Imre Lakatos

Knowledge is not made more true or false based upon the experience of
the person who holds it.

I respectfully disagree. Knowledge without experience is untested as
witnessed by the statement regarding kellets. Kellets can be useful
for reducing swing radius in a crowded anchorage under moderate
conditions, but do very little to enhance ultimate holding power of an
anchor, any anchor. The reason, as an experienced person would know,
is that the anchor rode, rope or chain, with or without kellet, will be
pulled nearly taut under heavy load.

On Sat, 27 May 2006 21:05:46 -0700, Stephen Trapani
wrote:

wrote:

I am not advocating any particular anchor, I thought the footage of
this test maybe of interest.


I do believe that any anchors performance can be enhanced with the use
of a kellet or Anchor Catenary.
A kellet serves more than one purpose:
#
Increase anchoring security and reduce the risk of the anchor dragging
by changing the angle of pull on the anchor to help it dig in
#
Reduce boat swing by up to 50%
They almost double the holding power of the anchor and reduce the
working load of the anchor by up to 50%.
"Having a lot of sag in the rode reduces shock loads and helps keep
the anchor dug in by reducing the angle between the rode and anchor.
The best you can do is an angle of "zero", which exists when the
anchor rode is flat on the bottom, and all the pulling forces are
horizontal. As tension increases, it reaches a point where the weight
of the rode is overcome, and the angle becomes positive. Positive
angles make the anchor work harder at keeping set, since the rode is
now pulling up on the anchor. If the tension continues to increase,
the catenary reduces to a straight line, and eventually the anchor
pulls out."

It is clear that some people respond to these informational posts from
links that havent read the material much less understood it.



Mic, please tell us something about you recent anchoring experiences,
e.g., type of boat you own, type of anchor/rode, bottom conditions,
weather, etc.

Knowledge is not made more true or false based upon the experience of
the person who holds it. For one thing, the person could have gotten the
knowledge from a very experienced person (as much of the links Mic posts
clearly are), for another, experience doesn't prevent anyone from being
wrong about anything, for another, theories should be judged upon their
adherence to the canons of rationality, not upon who they come from.

Well said and understood.

Heres and interesting thought.

2 lawyers in a civil matter both have the same number of years
experience, no agreement on the statue can be made. What percentage
does each lawyer have of being correct as decided by the court? 50-50
right? Or less than 50% chance of being right but still the same %
chance of being right accorded to each lawyer? If you have any
experience then you should have the answer;

I would say that for the most part I would concur with that which is
in many of the sailing informational links. Or provide the links as
something new or different, as it appears that these interests are in
common with others, with an exception it seems. Thats OK.



--
Stephen

-------

For any proposition there is always some sufficiently narrow
interpretation of its terms, such that it turns out true, and
some sufficiently wide interpretation such that it turns out
false...concept stretching will refute *any* statement, and will
leave no true statement whatsoever.
-- Imre Lakatos

Mic wrote:
A few observations:

Humm...but wouldnt that apply to the Rocna too?
It would seem to and was one of my first thoughts of this test.
that is probably why an anchor with a mini float attached to it tend
or seems to be effect in keeping it in a good or better setting
position.

Mini floats have the drawback of detracting from the anchor's overall weight
underwater, and also are difficult to construct with any decent amount of
durability.

I would think that the Bulwagga would be righted on the bottom every
time given it design.

The Bulwagga has three flukes mounted in an equilateral arrangement. This
means there is no right way up

The drawback is that only 2 of its 3 flukes are ever in use. Furthermore its
design is difficult to make strong enough (flukes are just flat plate - catch
one in rock or coral and see what happens). It is however an excellent,
superior alternative to Danforth-type anchors.


I do believe that any anchors performance can be enhanced with the use
of a kellet or Anchor Catenary.


waynebatrecdotboats is largely correct is his assertations that kellets are
of little ultimate use. They suffer from a catch-22 whereby they work well in
light conditions, but by the time conditions are bad enough that you care,
the rode will have been pulled nearly tight, and the kellet will make next to
no difference - and of course it is at this point that you would probably
like it to.

Do not rely on catenary from either chain or kellet to absorb shock. Use a
nylon snubber to do this.

Kellets are good at reducing your swing radius, and their functionality
really ends there. Put the weight of the kellet into the anchor instead, so
you have a larger anchor, and you will see a much better return on ultimate
holding power.

A good angle of pull on the anchor should be attained by the use of adequate
scope.

Those interested in the theory can study the math he
http://alain.fraysse.free.fr/sail/ro...ces/forces.htm
That site considers most factors involved and arrives at a sensible
conclusion with regard to "the best rode" that we can support on the basis of
experience.

Do not rely on catenary from either chain or kellet to absorb shock. Use a
nylon snubber to do this.

Kellets are good at reducing your swing radius, and their functionality
really ends there. Put the weight of the kellet into the anchor instead, so
you have a larger anchor, and you will see a much better return on ultimate
holding power.

A good angle of pull on the anchor should be attained by the use of adequate
scope.

Well said, and as I pointed out, there's nothing like experience.

On Mon, 29 May 2006 12:19:23 GMT, "craigsmith" u22396@uwe wrote:

Mic wrote:
A few observations:

Humm...but wouldnt that apply to the Rocna too?
It would seem to and was one of my first thoughts of this test.
that is probably why an anchor with a mini float attached to it tend
or seems to be effect in keeping it in a good or better setting
position.

Mini floats have the drawback of detracting from the anchor's overall weight
underwater, and also are difficult to construct with any decent amount of
durability.

Yep, but the design of the mini float has a purpose which appears, and
as I recall, in keeping it in a good or better setting position.
Which from the Rocna test seemed to show as being a factor in the
setting of an anchor and thus my observations of the design of the
Bulwagga.

I would think that the Bulwagga would be righted on the bottom every
time given it design.

The Bulwagga has three flukes mounted in an equilateral arrangement. This
means there is no right way up

Which would mean that is a good thing?

The drawback is that only 2 of its 3 flukes are ever in use. Furthermore its
design is difficult to make strong enough (flukes are just flat plate - catch
one in rock or coral and see what happens). It is however an excellent,
superior alternative to Danforth-type anchors.

This would tend to support the statement that there is no one anchor
for all conditions. Nor is there any controlled anchor test that
could be considered "ultimate", only relative, that I know of as most
every anchoring situation is a unique combination of variables,
granted there are similarities. Now if for example the Rocna tests
proved that another anchor was better would Rocna make those results
know? The good thing about the Rocna tests is that they made the
effort and those that see it can decide for themselves.



I do believe that any anchors performance can be enhanced with the use
of a kellet or Anchor Catenary.


waynebatrecdotboats is largely correct is his assertations that kellets are
of little ultimate use. They suffer from a catch-22 whereby they work well in
light conditions, but by the time conditions are bad enough that you care,
the rode will have been pulled nearly tight, and the kellet will make next to
no difference - and of course it is at this point that you would probably
like it to.

If the conditions cause the anchor chain to become taut there is no
cantenary effect from a kellet or chain. So it is not of "ultimate"
use under those conditions. But who said it was?
Wayne was just trolling. The fact that by using a kellet in heavy
weather anchoring is that a chain is less likely to become taut than
without one except in extreme conditons and circumstances. In other
words a chain will go taut latter (if at all depending on the
conditons) with the use of a kellet or more chain than sooner without
based on experience and knowledge. At which point the concern would
not just be that of ultimate holding power but chafe, deck hardware
strenght, integrity of snubbers, etc.

A kellet ought not be a substitute for scope but under certain
conditions and reasons an anchors performance can be enhanced.

Gord May who you are aware of and is probably one of the most helpful
and respected persons in the internet sailing community:
http://www.cruisersforum.com/forums/...read.php?t=276
"In heavy weather, I always deploy 15 Lb "Sentinal" (Kedge) weights,
suspended a few feet above bottom."
Gord May
GordATBoatpro.zznDOTcom ~ (Requires Decription)

Although he does not give his reasons why, and I am sure that he
doesnt believe that it will have an effect on a taut chain. But it is
likely that he believes that the use of a kellet in those conditions
is an aid to anchoring and to delay or totally avoid a taut chain that
would/might occur without it use.

http://www.anchorbuddy.co.nz/
"They...
Increase anchoring security and reduce the risk of the anchor
dragging by changing the angle of pull on the anchor to help it dig in
*
Reduce boat swing by up to 50%
*
Make life at anchor much more comfortable
Anchor weights, (also known as chums, kellets, sentinels, anchor
angels) have been used for generations to anchor boats more securely.
They almost double the holding power of the anchor and reduce the
working load of the anchor by up to 50%. They are an advanced
technique in safe, secure anchoring."

Do not rely on catenary from either chain or kellet to absorb shock. Use a
nylon snubber to do this.

Kellets are good at reducing your swing radius, and their functionality
really ends there. Put the weight of the kellet into the anchor instead, so
you have a larger anchor, and you will see a much better return on ultimate
holding power.

So the claim that Anchor Buddy makes "They almost double the holding
power of the anchor and reduce the working load of the anchor by up to
50%." is false? Ultimate holding power has to do as much with bottom
conditions, boat windage, anchor design, sea conditions and resetting
ability than just weight alone.

http://www.anchorbuddy.co.nz/faq.html
This faq reasonably addresses the issue of using a larger anchor and
the practical aspects of a kellet. Thats not to say that a bigger
anchor is not better, and how big is big enough isnt always a
consenus. And I have read time and again that its not the weight of
the anchor but its geometric design, but this too is often
contradicted.

And certainly there is no consenus on what the best anchor is,
probably because there is no one best anchor for all conditions. So
for the ultimate holding power the anchor has to match the bottom
conditions.

A good angle of pull on the anchor should be attained by the use of adequate
scope.


Sailing since '67 Mic.