Torries

any event, the re-galvanizing

must be done before corrosion

reduces the diameter of even

a single link, and the company

doing the process must be

certifi ably competent.

The fall in the chain locker

prevent “pyramiding” from

jamming the hawse hole.

Ideally, the locker should be

as far aft as possible to mini-

HANDS-ON SAILOR

should be deep enough to

mize hobbyhorsing from extra

weight in the bow. The locker

should drain so that the chain

does not remain immersed in

salt water, which can rapidly

attack the galvanizing.

The chain should never be

directly attached to the boat.

Fasten a rope strop leading

from a stout D-ring in the

locker to the chain’s end. It

should be long enough to

escape the hawse hole so that

in the event of an emergency,

from the foredeck, the rope

can be buoyed and then cut,

and the tackle dropped in an

instant.

ANCHORING 101

Now let’s get this tackle on the

ground. Unless you are using

a moving downwind drop, as

is sometimes necessary under

sail in crowded anchorages, it

is best to turn the boat up into

the wind and let your speed

bleed to zero. Let out just

enough chain for the anchor to

reach the bottom. Drift back-

ward slowly, deploying chain at

the same rate as the drift. This

ensures that the chain does

not drop down on the anchor

in a heap and foul it. Once you

have achieved a 3-to-1 scope,

slowly increase the tension on

the rode. This will turn the

anchor into the setting posi-

tion without snatching it out

of the bottom. Then simply

stop. Let the anchor weight

settle into the bottom. Next,

slowly exert considerable force

via the engine’s reverse or, if

engineless, back the mainsail

to test the set.

Even if the anchor drifts a

bit, this process will at least

give you a feel for the bottom,

and that is valuable knowl-

edge. Of course, you have

already scrutinized the depth

sounder to get a feel for foul

ground. Don’t fall into a casual

attitude of “She’ll be right,

mate.” If the set isn’t fi rm and

exactly where you want it, do

it again. Ten more minutes of

work now will translate into

hours more sleep tonight.

Look around with a sus-

picious eye at the vessels in

your area. Notice if they are

anchored or on moorings, as

that will dramatically aff ect

the diameter of their swing.

How much scope do the

anchored vessels have out?

Where will the winds be in

the night? What will the turn

of the tide do? Look for the

usual suspects: vessels with

thin or chafed rope rodes,

mooring lines not led through

proper chocks, bottoms obvi-

ously fouled. If a vessel has

been neglected long enough to

be declared a marine reserve,

probably so has the ground

tackle to which it’s attached.

SCOPE IT OUT

Once you have selected your

safest location, determine the

maximum scope to deploy.

When you’re alone and with

swing room, there is no such

thing as too much scope. But

300 feet of light line on a ves-

sel with a penchant to “hunt”

in gusts is the scourge of a

crowded anchorage.

In its simplest terms,

scope is defi ned as the ratio

between the depth of water

and the length of rope or chain

deployed. To fi ne-tune that,

however, you must add the rise

from the waterline to the bow

rollers, additional wave height

in storms, and tidal rise and

fall. This may not seem signifi -

cant until you anchor in Tierra

del Fuego in 10 feet of water,

deploy 40 feet of rode assum-

ing a 4-to-1 scope ratio, and

confi dently retire. The 45 feet

of tidal rise in the night will

snatch your anchor smartly

from the bottom and set you

swirling adrift.

Conventional wisdom calls

for a minimum scope of 3-to-

1, ranging when possible up to

5-to-1. The greater the scope,

the less the angle of upward

pull on your anchor and the

better its holding power. This

presumes a fl at bottom, how-

ever (see Figure 4a). If you are

forced to anchor on a con-

trary slope, as is often the

case, such as in Vava‘u, Tonga,

the downward inclination of

the bottom will increase that

angle, thus decreasing the

holding power of the anchor

(see Figure 4b). The anchor is

pulled out of the side of the

mountain, so to speak, and

the farther it drifts down, the

smaller the scope becomes.

In this situation, the best

strategy is plenty of catenary

eff ect from excess chain and

perhaps even an additional

anchor weight. Even if the

anchor does pull out of the

downward-sloping wall, the

extra scope will help it reset

any event, the re-galvanizing

must be done before corrosion

reduces the diameter of even

a single link, and the company

doing the process must be

certifi ably competent.

The fall in the chain locker

should be deep enough to

prevent “pyramiding” from

jamming the hawse hole.

Ideally, the locker should be

as far aft as possible to mini-

mize hobbyhorsing from extra

weight in the bow. The locker

should drain so that the chain

does not remain immersed in

salt water, which can rapidly

attack the galvanizing.

The chain should never be

directly attached to the boat.

Fasten a rope strop leading

from a stout D-ring in the

locker to the chain’s end. It

should be long enough to

escape the hawse hole so that

in the event of an emergency,

from the foredeck, the rope

can be buoyed and then cut,

and the tackle dropped in an

instant.

ANCHORING 101

Now let’s get this tackle on the

ground. Unless you are using

a moving downwind drop, as

is sometimes necessary under

sail in crowded anchorages, it

is best to turn the boat up into

the wind and let your speed

bleed to zero. Let out just

enough chain for the anchor to

reach the bottom. Drift back-

ward slowly, deploying chain at

the same rate as the drift. This

ensures that the chain does

not drop down on the anchor

in a heap and foul it. Once you

have achieved a 3-to-1 scope,

slowly increase the tension on

the rode. This will turn the

anchor into the setting posi-

tion without snatching it out

of the bottom. Then simply

stop. Let the anchor weight

settle into the bottom. Next,

slowly exert considerable force

via the engine’s reverse or, if

engineless, back the mainsail

to test the set.

Even if the anchor drifts a

bit, this process will at least

give you a feel for the bottom,

and that is valuable knowl-

edge. Of course, you have

already scrutinized the depth

sounder to get a feel for foul

ground. Don’t fall into a casual

attitude of “She’ll be right,

mate.” If the set isn’t fi rm and

exactly where you want it, do

it again. Ten more minutes of

work now will translate into

hours more sleep tonight.

Look around with a sus-

picious eye at the vessels in

your area. Notice if they are

anchored or on moorings, as

that will dramatically aff ect

the diameter of their swing.

How much scope do the

anchored vessels have out?

Where will the winds be in

the night? What will the turn

of the tide do? Look for the

usual suspects: vessels with

thin or chafed rope rodes,

mooring lines not led through

proper chocks, bottoms obvi-

ously fouled. If a vessel has

been neglected long enough to

be declared a marine reserve,

probably so has the ground

tackle to which it’s attached.

SCOPE IT OUT

Once you have selected your

safest location, determine the

maximum scope to deploy.

When you’re alone and with

swing room, there is no such

thing as too much scope. But

300 feet of light line on a ves-

sel with a penchant to “hunt”

in gusts is the scourge of a

crowded anchorage.

In its simplest terms,

scope is defi ned as the ratio

between the depth of water

and the length of rope or chain

deployed. To fi ne-tune that,

however, you must add the rise

from the waterline to the bow

rollers, additional wave height

in storms, and tidal rise and

fall. This may not seem signifi -

cant until you anchor in Tierra

del Fuego in 10 feet of water,

deploy 40 feet of rode assum-

ing a 4-to-1 scope ratio, and

confi dently retire. The 45 feet

of tidal rise in the night will

snatch your anchor smartly

from the bottom and set you

swirling adrift.

Conventional wisdom calls

for a minimum scope of 3-to-

1, ranging when possible up to

5-to-1. The greater the scope,

the less the angle of upward

pull on your anchor and the

better its holding power. This

presumes a fl at bottom, how-

ever (see Figure 4a). If you are

forced to anchor on a con-

trary slope, as is often the

case, such as in Vava‘u, Tonga,

the downward inclination of

the bottom will increase that

angle, thus decreasing the

holding power of the anchor

(see Figure 4b). The anchor is

pulled out of the side of the

mountain, so to speak, and

the farther it drifts down, the

smaller the scope becomes.

In this situation, the best

strategy is plenty of catenary

eff ect from excess chain and

perhaps even an additional

anchor weight. Even if the

anchor does pull out of the

downward-sloping wall, the

extra scope will help it reset

HANDS-ON SAILOR

TIM BARKER

january/february 2017

cruisingworld.com

94

ALVAH’S TIP

If the set isn’t firm and

exactly where you want

it, do it again. Ten more

minutes of work now

will translate into hours

more sleep tonight.

Figure 4b

Figure 4a

The angle of pull at a given scope ratio assumes a fl at

bottom. That angle is increased by the incline of the bottom,

eff ectively decreasing the ratio to below the minimum of

3-to-1. In the examples above, both anchors are in 30 feet of

water, and both boats have out 90 feet of rode, but the boat

in Figure 4a will have better holding than the boat in 4b.

CRW0217_HOS1_Anchoring.indd 94 11/22/16 10:26 AM