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Sand
Anchor Test provided by West
Marine, for additional information dial
(800)BOATING
© West Marine Products, Inc.
West Marine Traditional 8
This was the lightest anchor tested in the second round of test. It
is similar to the 8-S Danforth Standard anchor.
The Traditional 8 engaged after some dragging, and held to 550 lbs
and 1200 RPM. We then pulled it a second time to 760 lbs., and when it
was retrieved the shank was bent to the side approximately 30°. We did
not veer on the anchor so the damage was not due to our purposely
pulling sideways on the shank. The anchor did not drag, however, even
with the bend.
We were able to straighten the shank and continue testing at Site C.
It dragged across the sand in the typical "tripod" fashion,
with one fluke tip, stock tip, and shank touching. When we flipped the
anchor over, it set immediately and held to 1080 lbs. When it was dug
out of the bottom, it was found to be about 8" under the surface,
and had rolled about 30°.
Hooker Economy 13
This is a variation on the Danforth anchor type, using flukes bent in
the center for stiffness, and a shank made from rod stock. The hollow
shank lets a ring to be used as an attachment point, which allows the
anchor to be withdrawn crown first should the anchor become stuck.
In our tests, however, the anchor showed no interest in sticking in
anything. At Site B, we were unable to get it to engage the bottom, and
registered 60 lbs. of tension as it bounced along the bottom. At Site C,
the anchor reared up and scraped along the surface. When the anchor was
forced into the sand in a normal digging attitude, it popped out at 95
lbs. of tension.
We could not find any positive attributes of this anchor, other than
price.
Rule/Danforth H-960
This is a slightly modified version of the 12-H anchor that Danforth
has made for years. This version has had its stock width reduced from
the original 21-1/2" to 17-1/2", which the engineers at Rule
indicate has no effect on its performance. Like other H series anchors,
it has T section flukes, is made from high-tensile steel, and has a
forged shank.
At Site B, the anchor engaged immediately and held to 1000 lbs. of
tension. We then weighed and re-set the anchor, and it registered 960
lbs. After engagement, we turned the boat 90° to see if we could bend
the shank, but the anchor continued to hold and was undamaged.
At Site C, the anchor engaged quickly, and buried until it was
8" under the surface. We pulled it to 920 lbs. and it showed no
signs of dragging.
Rule/Danforth S-920
This is a slightly modified version of the original 13-S anchor. It
has a shorter stock than the original, and it now uses a plate shank
rather than the original forged shank.
At Site B, the S-920 dug in immediately and held to 940 lbs. On the
second pull, it held to 880 lbs. where it let go suddenly. The anchor
was able to reset, and showed no signs of distortion when retrieved. We
did not test the S-920 at Site C.
Creative Marine Max Anchor
The Max appears to be a combination of the curved shank of the Delta
so that it is self-launching, combined with a large scoop-shaped fluke
like the Bruce. It has a reinforcing rib which runs down the length of
the shank, terminating about 4" above the fluke. It appeared to be
"light" to the testers, meaning that it has a lot of surface
area in the flukes compared to the structural, non-fluke components.
After some dragging, the Max engaged the bottom at Site B and held to
720 lbs. of tension. At this point it released, and we could not get it
to set again. When retrieved, the shank was bent about 30° about
2" above the fluke surface. We could not bend the shank back, so
the testing at Site C was attempted with the bent shank. This made the
anchor unstable so that it would not engage the sand. A new, modified
Max was requested from Creative Marine, and will be tested in a future
test.
Rule/Danforth D-1150
The Deepset® style of anchor was introduced in the mid-80s as an
improvement to the Standard and Hi-Tensile designs. It uses a spring
steel shank which is much thinner than the normal steel shanks, and a
smaller crown assembly with parallel crown plates. These changes are
said to reduce penetration resistance, and allow the anchor to dig
deeper and engage higher sheer strength soils. This design philosophy
has also been used in the Deepset Hi-Tensile®, Deepset® VSB® mud
anchor, Deepset® Plow.
The 10 lb. D-1150 was pulled to 940 lbs. at Site B, where it released
suddenly. We suspected that the anchor might have been damaged, and
retrieved it, only to find a knot in the chain about 15' from the
anchor. It was not obvious whether the knot could have caused the
release, so we redeployed the anchor. It held the second time to 980
lbs.
At Site C, the D-1150 was pulled to 840 lbs. and buried 7" under
the surface. After retrieval, the anchor was jammed and the flukes would
not pivot. We then placed the anchor on the sand with the flukes up, and
the anchor showed no signs of digging into the bottom. It seemed that if
a boat were to pull hard on the Deepset anchor, then upset the anchor
due to tide or wind, the anchor might not ever reset.
Bruce 5 KG, 11 lb. Anchor
This is currently the smallest Bruce anchor that is imported into the
U.S. It is a cast one piece anchor, with a three-palmed fluke. Bruce
anchors have a reputation of engaging the bottom quickly, staying
embedded when veered, and having only moderate holding power.
At Site B, the Bruce engaged immediately, then began to drag at a
constant 300-350 lbs. of tension. We lengthened the scope from 5.3:1 to
8.2:1 to see if it would help the anchor, and its holding power
increased to 580 lbs., although the anchor continued to drag slowly.
Disappointed by this performance, we tested it again before we left
the site. At 5.3:1 scope it held 260-450 lbs., but the anchor was
dragging the entire time. It would seem to hold for a moment, then
release, then re-engage. While we were able to get a reading of 800 lbs.
of tension, the boat was dragging the anchor at substantial speed and
could not be said to be anchored.
At Site C, the Bruce plowed a perfectly straight furrow while at a
15° angle of attack to the seabed. We pulled it at tensions from
200-380 lbs., but it would not dig deeper or pop out. Its performance
was very consistent and stable.
Super Hooker M-740
This is a very similar anchor to the Rule/Danforth S-920, but
marketed by Tie-Down Engineering, who manufacturers the Danforth line of
anchors for Rule. It has a very short stock protruding from each fluke,
leading us to surmise that it would be rotationally unstable. While we
saw evidence that this design rotated more than other similar anchors,
it did not disengage due to rotation.
During the two pulls at Site B, the M-740 held 850 and 860 lbs.
without dragging. At Site C, it held tensions of up to 1,060 lbs. and
was found to have rotated 45° when it was eventually dug up. During the
next pull, the anchor popped out of the sand due to having picked up
some welding rod between the flukes and shank, which was not interpreted
as being the fault of the anchor. It does point out,
however, that the Danforth-type of anchor has a tendency to snag on
items on the surface or in the seabed, and can be made to disengage when
it hits something.
Luke 40 lb. Fisherman Anchor
This was the oldest design, and heaviest anchor, that we tested. At
Site B, we were unable to attain a tension greater than 300 lbs. and the
anchor seemed stable dragging at between 100 and 200 lbs. Even at idle
RPM, our test boat caused the anchor to drag. Additional anchor line did
little to increase its holding power.
At Site C the Luke simply plowed ahead slowly with only 200 lbs. of
resistance. When we pushed the fluke into the sand with body weight, the
tension increased to 390 lbs, only to relax to 200 lbs. again. We were
very surprised by the limited penetration in either sand bottom.
The geometry of the anchor held the flukes in a steep angle of
attack, and it looked as if they would quickly dig in. However, the
small surface area and rounded edges of the flukes did not provide a
sharp bite into the bottom.
Delta 6 KG, 14 lb. Anchor
The Delta is a modern version of the plow anchor, with sharper
sections and no shank hinge. We tested the second smallest anchor.
It engaged immediately and held up to 1000 lbs. with no apparent
movement on the first pull at Site B. On the second pull, it again
reached 1000 lbs., but did so while dragging slightly.
At Site C, the Delta quickly righted itself from several different
attitudes and dug in. In the unsaturated sand above the tide line, the
Delta held about 500 lbs. while slowly creating a furrow in the sand.
This tension increased to 790 lbs. as the sand got wetter, but still
with some perceptible movement.
It was the opinion of the testing crew that the Delta has the best
overall performance of any of the anchors tested on May 20.
Digger 15 Anchor
We tested the Digger for a second time, after careful instructions
from the manufacturer to use exactly 5:1 scope and no chain. It did not
dig in perceptibly in Site B, and we could only register 30 lbs. of
tension.
At Site C, the Digger repeated reared up, fell over, and reared up
again. It was completely unstable and did not register any tension. Even
when we pushed its flukes into the sand, it popped out and fell over.
Mushroom 12 lb. Anchor
According to the manufacturer, this anchor is "a very popular
anchor for the ardent fisherman." We believe that this reputation
is based on its unlikely tendency to snag on bottom debris in reservoirs
or rivers. It also exhibited no tendency to snag on a sand bottom. It
dragged on its side with one edge partially imbedded, and produced no
more than 40 lbs. of resistance.
River style 12 lb. Anchor
According to the manufacturer, this anchor is "ideal for
fisherman frequenting waterways with sand, weed, gravel, or stone
bottoms. Recommended for strong current areas." From our
observations, it is appropriate for a paperweight, at most. This anchor
behaved similarly to the Mushroom, and developed no more than 40 lbs. of
tension.
Navy type 20 lb. Anchor
This anchor looks like a large ship's anchor, with bulky cast flukes
and a pivoting shank. It has aluminum paint for protection, which
corroded after one use in salt water, even after rinsing. It did not
penetrate into sand at all, and produced a momentary tension of 60 lbs.
Conclusions
1. Our test looked at the ability of popular anchor designs to
penetrate and hold in a sand bottom. We attempted to measure the
tension that an anchor could withstand without perceptible dragging.
This is difficult, however, since it is hard to measure the point at
which an anchor begins to drag without observing it underwater. It
is even difficult when the anchor can be observed, since it is
frequently so deep in the seabed as to make observation impossible.
2. It is difficult to surmise the failure mode of an anchor from
the surface. Either observation by SCUBA diving or shallow water
testing is necessary to determine what happens.
3. Similar bottom conditions may have widely varying results,
based on our experience with the Performance anchor. It is difficult
to explain why it would not set on one side of the wharf, yet is set
easily on the other side, nor is it possible to explain why it set
better with reduced scope.
4. Anchors which come highly recommended, even those which are
successful in the marketplace, may not perform in the real world.
The most confusing results were those of the Hans-C, which seems
like it should work, yet never has in our tests. Perhaps we should
test a larger version.
5. Anchor stability, once the anchor has engaged, is as important
as high tension ratings. The FOB rotated out of the bottom after
recording loads over 800 lbs. This might cause a false sense of
security when an anchor appeared to be set securely. The Max anchor
bent after withstanding 740 lbs. and would not re-set.
6. An anchor needs to meet various criteria to work well for
boaters. Most anchors have some strengths and some weaknesses, and
an anchor that works well in one application may fail in another.
For example, we did not credit anchors for their ability to be retrieved
in snag-prone bottoms like reservoirs. Anchors like the
Mushroom, River, Economy, and Navy might be better suited to this
use than the higher holding power yachtsman's anchors.
7. An anchor should also engage the bottom quickly, every time it
is deployed. It should not set on some occasions and not on others.
It should also be capable of remaining in the seabed as the vessel
veers in the wind and current. And anchors should not be upset by
minor debris in the seabed.
8. One area where we need to do more testing is the effect of
anchor weight on consistency of performance. Some anchors appeared
to skid along the bottom without getting initial penetration, and we
suspect that the larger version of each of these anchors might
engage much more consistently. In other words, the holding power to
weight ratio may not be a smooth relationship, but may have a
discontinuity in the curve at a particular weight.
Other anchors, like the Delta, grabbed every time they were used,
even though they were small sizes. We suspect that this might be due
to the central fluke tip, which can exert high localized pressures
on the bottom due to the small surface area.
9. The Danforth-type anchors, as a class, appeared to hold
tenaciously and continue digging as load was applied. Several
demonstrated roll instability, and appeared that they would have
popped out of the bottom had we continued to pull on them with
increased tension.
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