How To Select An Anchor
And Anchor Rode
selecting anchor rode
There’s little doubt that an all chain anchor rode is the very
best solution in most cases. Chain is much stronger than any nylon
anchor rode, it doesn’t suffer from chafe and the weight of the
chain works as a shock absorber, reducing the loads on the boat
if there is any surge or other shock load on the anchor system.
However,
an all chain rode is very expensive, it’s very heavy (and it’s in
the bow, where you least need it), hard to handle, it probably requires
a chain windlass to retrieve it and it needs a snubber so that any
chain shock load is absorbed before it’s transmitted to the boat.
The best compromise for a sailboat is probably laid nylon line
with 20-30 ft of chain before the anchor. Nylon stretches by about
25% at 50% of its breaking strength and recovers from heavy loads
better than braided line. Practical Sailor recommends New England
Rope’s Premium 3 strand nylon.
what size nylon
rode and chain?
This depends to a great deal on where you usually anchor, the
bottom conditions and the worst weather conditions you expect to
encounter.
As
a starting position you might consider :
- For a boat length 20-25ft: ½ inch nylon rode with 20 ft of
3/16 inch high test or BBB chain
- For a boat length 26-30ft: ½ inch nylon rode with 30 ft of
¼ inch high test or BBB chain
- For a boat length 31-35ft: 7/8 inch nylon rode with 35 ft
of 5/16 inch high test or BBB chain
If
you’re headed offshore, go up at least 2 sizes in both rode and
chain.
A
tip. Buy domestic made chain. Imported chain may or may not be of
the quality specified and your boat is worth a whole lot more than
30 ft of chain.
For your
primary anchor rode you’ll need at least 10 times the depth of your
deepest anchorage. So if your deepest anchorage is 20 feet you’ll
need (20 x 10) = 200 ft of anchor rode. This allows for a 7:1 scope
on your anchor rode in fairly shallow water (20 feet). As your anchor
depth gets greater, you can reduce the scope somewhat, even down
to 3:1 in very deep water.
The rode to chain and chain to anchor connections should be
by shackle, at least one size larger than the chain (i.e. ¼ inch
diameter chain needs a 3/8 inch diameter shackle). The shackle pin
must be securely moused with monel wire. The nylon rode should have
a metal thimble spliced into the end connecting to the chain.
The bitter end of the nylon rode (the end connected to the
boat) should not be connected directly to the boat inside the chain
locker. There should be a tail of light line connecting the end
of the anchor rode to the chain locker. This tail should be long
enough to reach the bow roller from the chain locker. The reason
for this is so that you can cut this light line if you ever need
to get rid of your anchor quickly in an emergency.
anchors
Here’s
where we get into dispute territory. I know every sailor has an
opinion on the best anchor for a given bottom condition and will
argue all night about the pros and cons of different anchors.
I’m going to slide out from under by using the results of Practical
Sailor’s extensive testing of anchors under $200. No correspondence
will be entered into ;-)
Practical Sailor has conducted extensive tests over the years
on many different makes and models of anchors suitable for sailboats
in several different bottom conditions. For anchors costing less
than $200, their conclusions are:
|
Anchor Guide
|
| |
setting rank
|
holding power
|
average
|
| Name |
weight
|
sand
|
mud
|
combined
|
sand
|
rank
|
mud
|
rank
|
holding
|
rank
|
| Barnacle |
28#
|
16
|
9 tie
|
12 tie
|
355#
|
9
|
800#
|
1
|
577#
|
4
|
| Bruce |
22#
|
3
|
2 tie
|
1
|
307#
|
11
|
550#
|
8
|
429#
|
10
|
| Bulwagga |
17#
|
1
|
8
|
4 tie
|
816#
|
2
|
680#
|
3
|
748#
|
2
|
| Lewmar Claw |
22#
|
8
|
2 tie
|
4 tie
|
283#
|
14
|
520#
|
9
|
401#
|
12
|
| CQR |
35#
|
15
|
2 tie
|
9
|
583#
|
3
|
760#
|
2
|
672#
|
3
|
| Danforth
Deepset II |
20#
|
14
|
15
|
14
|
363#
|
8
|
640#
|
5
|
502#
|
6
|
| Delta |
22#
|
13
|
1
|
7
|
496#
|
4
|
610#
|
6
|
553#
|
5
|
| Fortress FX-16 |
10#
|
9
|
13
|
11
|
471#
|
5
|
420#
|
12
|
446#
|
8
|
| Hans C-Anchor |
15#
|
17
|
12
|
15
|
0#
|
17
|
350#
|
15
|
175#
|
15
|
| Herreshoff |
17#
|
6
|
-
|
-
|
300#
|
12
|
-
|
-
|
-
|
-
|
| Hydro-Dyne |
10#
|
failed
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
| Nautical Engineering |
20#
|
11
|
14
|
12 tie
|
235#
|
15
|
390#
|
14
|
313#
|
14
|
| Seagrip |
33#
|
12
|
-
|
-
|
200#
|
16
|
-
|
-
|
-
|
-
|
| Supermax (adjutable shank) |
26#
|
7
|
2 tie
|
3
|
410#
|
7
|
430#
|
11
|
420#
|
11
|
| Supermax |
26#
|
5
|
2 tie
|
2
|
350#
|
10
|
400#
|
13
|
375#
|
13
|
| Spade Model
80 |
16.5#
|
2
|
7
|
6
|
1000#
|
1
|
660#
|
4
|
830#
|
1
|
| Vetus |
12#
|
4
|
9 tie
|
8
|
285#
|
13
|
590#
|
7
|
438#
|
9
|
| West Marine
Performance |
25#
|
10
|
11
|
10
|
456#
|
6
|
460#
|
10
|
458#
|
7
|
|
Note: the
Bruce anchor os no longer made for recreational boats. The Lewmar
Claw is a close copy.
The figures give
the breakout loads for each anchor in the respective bottom conditions,
and the rankings are out of the 15 anchors that passed the tests.
Setting rank =
how quickly the anchor set when under load compared to the others
For non-US sailors,
the # sign = pounds weight or load.
The
22# Lewmar Claw and the 20# Danforth are quoted as suitable for
a 30-35ft boat, but I think it's prudent to go one size higher than
recommended by manufacturers. So I'd select the 22# Lewmar Claw
for a 25-30ft boat because it sets well in any bottom material.
I'd also like the 10# Fortress FX-16, which is an aluminum version
of the Danforth, as a lightweight second anchor.
The Spade Model
80 is an excellent aluminum plow style anchor that won this test.
The shank is bolted to the plow and can be disassembled for stowage.
It's also very expensive.
You can check
the costs of some of these anchors and rode at West Marine (use
the link below if you like)

|