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craigsmith
 
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Default Demonstration footage of boat anchors

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. 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.

Mic 67


Glenn, we did not include in our video the Spade, nor the Delta, SARCA,
Buegel, and a few others, mostly for reasons of time. That video is already
nearly 10 mins long, and we wanted to keep our message simple: old types bad,
new types good. The most popular types are plows and claws so that is what we
target.

Your comments about scope are just plain wrong. This is important. No anchor
is designed to work with a particular scope; on the contrary, all anchors
work better the more scope you have. The ideal is horizontal, hence the use
of chain or kellets to attain an angle lower than that of a straight line
between the anchor and the boat. We therefore use a horizontal angle in any
testing to provide a level playing field; otherwise those boaters more
experienced would object to a particular scope being used, as it may favor
(or hurt) a particular anchor.

The shank, articulated or not, has nothing to do with scope affecting how the
anchor sets. The Delta, Spade, and Rocna, all depend on what's called three-
point geometry for their setting; i.e. they lie on their sides initially then
screw into the substrate.

The "big hoop" does not compensate for "poor balance"; rather the roll-bar
ensures the anchor rights itself, without relying on a dedicated weight in
the tip, an inefficiency common amongst other designs.