Anchoring: too much scope?

[James V]

Anchoring can best described as a religon. Nothing in stone.
First - the scope ratios is from how deep the anchor is set and to where the anchor is tied off on the boat + waves and wind.
examples - if your water dept is 5 feet 7:1 is 35 feet of schope, Wrong. The bow is about 4 feet above waterline. That is 9 feet X 7 = 63 feet.
If your anchoring in soft bottom and you bury the anchor 2 feet then 5 + 4 + 2 = 11 X 7:1 scope = 77 feet
Now add waves of passing boats 3 feet tall then 5 + 4 + 2 + 3 = 14 X 7 = 99 feet of scope.
This is assuming that you have the right anchor for bottoms conditions and it is heavy enough for wind and bottom conditions. 99 feet vers 35 feet of scope in 5 feet of water. If you only put out 35 feet of rode and had some wind and a boat come by at the same time the anchor will come up and you will have to reset. I hope you are on the boat and awake.

I stern anchor and use a yoke with 30 feet of 5/14 BB chain. I have draged several times. I use the anchor drag alarm on my GPS all the time.

Use a gread deal of caution in crowed anchorages. Talk to people before anchoring always plan enough time to mave to a different anchorages. When possible anchor in less water than the other boats can drag into you. This does WORK!

Pray well, James V

[Boblee]

Boy just read this from the start and reckon you blokes must all be able to anchor on a football sized area or open sea.
We have to anchor every night when traveling and every single situation is different eg bottoms,currents, tides and restriction in movement but unless expecting huge winds or on a poor bottom we normally only use 5-1 scope but will nearly always have two anchors out either one to starbord 45deg and the other to port 45 deg or running dead ahead and astern but it all depends on swinging room and tides/current.
We got caught last year when the wife woke at 4 oclock with a gale going but with changing directions in a narrow river so had to actually shorten up and hold with the motor, it only lasted 20 mins but every night it happened about an hour later until we actually saw what was causing it.
In the bottom Eastern corner of our Gulf of Carpentaria they get some pretty freaky things happening with tides and winds etc and in this case it was whats called the "morning glory" which we finally saw in daylight and it was spectatcular but no one had warned us about the rolling winds when you were on the water
For the record we use a Sarca anchor as the main and if we don't expect much problem we use a large Danforth as a helper but have just about given up using it and now use the smaller Sarca from the dinghy due to dragging on anything but sand both have 6m of 5/16 chain.
May look at getting a better secondary anchor (another Sarca) this year as the area we are going to has up to 10m tides and very variable bottoms and of course with tides like that you have to be very careful with currents along the edges of islands etc.
The very first night we got the boat we dragged the Danforth in mud with only a medium wind and ended up in the willows 100m away with scratches along one side of the boat so will never ever trust the danforth but it's been a great learning curve, the only advice I can give is use as much scope as you can and always use two anchors if in doubt but most importantly have someone on board who is a light sleeper and never trust any anchor or any bottom which can change drastically in depth and composition with slight movement.
Also never trust anyone else to drop the anchor took a mate away for the first part last year and after dragging because he dumped the chain on top of the anchor twice I learnt that I had to do it myself even though he looked like he did it ok.
As suggested earlier drop the anchor til it hits the bottom then feed it out as you drift or motor back, we have markers every 10 metres along the rope.

[Boblee]

Double post computer has the go slows and tried again.

[Boblee]

Yep another double post.

[hart]

I'm anchored out right now. Warm enough and shallow enough (8 feet) I swam down and checked the anchor set by hand yesterday afternoon. Then I "volunteered" to do the same thing for my neighbor up current.

boy he thought I was a nice guy. And I knew he wouldn't drag into me. Win, win, lol.

[Indulgence]

While I'm meandering through the bay looking for a good spot to
anchor, I ask the crew on boats I'm passing what they have out for
scope. Then I'll more or less emulate the norm. In these crowded
anchorages I find an awful lot of folks only put out what they believe
to be 3:1 for overnight. Scary.

I'm not sure if this is right or not, and I get some truly nasty looks,
but I motor right up to the stern of the boat I want to have in front
of me and drop my anchor there. I mean, he's not coming any further
downwind or downcurrent, right?

I'll figure out what I should have for scope and that becomes the minimum.
After that I'll let out as much of my 250' as there's swing room, often all of it.
Gotta watch incoming boats, if everyone else has a really short leash they
don't realize I'm that far from my anchor. An anchor buoy would be a brilliant
addition.

[Boblee]

Indulgence
I would be very unsure about setting the anchor so close to someone else especially with a Mac and it's sailing habits and especially with so much scope.
You mention a "bay" but hopefully it is a still water and not subject to tides but even a stillwater can get wind changes during the night and if your neighbour only has 50' out and you have 250' you will not be popular unless you are setting a second anchor on the stern.
A problem with too much scope in certain settings can be that as the boat sails around it will drag the rope over every snag down there which can get messy especially if you are unsure how or what it is hooked on.
By running two anchors either port and starbord off the bow or bow to stern you not only restrict the sailing but also the drag area with wind and tide changes and provided you still have at least 3-1 scope at high tide on both anchors (providing one is not a Danforth type) you shouldn't? drag especially if you have set them correctly but remember as the tide and wind changes your anchor needs to reset which can be a problem if the boat sails directly over the anchor and fouls it with the rope etc.

[Rick Westlake]

I got the word on the Kiwi Anchor Rider - it's $350 plus shipping.

A Hindu sentiment comes to mind: Holy Cow!

I think my homemade 20-lb kellet will be perfect for seeing if a kellet will help me with the "anchor samba." It may also help me shorten scope a bit.

BTW, yes, an anchor buoy is a very good idea - even better, you can tie it to the crown of the anchor as a trip line. (And if you make it look like a crab-pot float, that may keep others a little further away from your hook!)

[c130king]

Rick,

How do you know how far to let out your kellet? Do you just drop it until it hits the bottom?

Jim

[Catigale]

I think its worth mentioning James' post above to highlight scope calculations...note how the 'first calculation' of only 35 feet of rode needed turned into 99 feet once the factors of deck height, anchor depth, and waves/wakes/chop are taken into account.

I have a snap shackle that I can attach to the rode on the boweye - it lowers my deck height by 2 feet, and also eliminates chafe (my rode comes over the bow roller, down to the shackle, and off to the anchor.

[Rick Westlake]

Rick,

How do you know how far to let out your kellet? Do you just drop it until it hits the bottom?

Jim

The directions from the Kiwi Anchor Rider web site said to pay it out till it's just short of the bottom, at low tide. This isn't all that significant in the upper Chesapeake Bay; tides don't often exceed 2 feet in my home waters. Somewhere like Puget Sound, though, it would make a real difference.

I tried the kellet out Friday night - not a "good test," as I was in a creek with very little wind & wave exposure. But Bossa Nova sat quietly over the kellet, pivoting bow-in-place to the breath of breeze that did reach her. The "anchor watch arc" that I painted on my GPS last year was minimized down to little more than the position-error jump you get from multi-path reception around trees and buildings.

As I'd said above, I made my kellet is 20 lbs of lead (scuba weights), lashed together with a spare captive-pin shackle to ride the rode and a gate-hook for the kellet's pendant. (Or would you call its line a "rode" too?) After I set the anchor, I shackled the kellet to the anchor-rode and lowered it until I could feel it touch bottom, then I raised it a hand's breadth and cleated it off. Worked like a charm, though I may get a good solid Wichard spring-hook carabiner to replace the rode shackle (just for convenience).

[c130king]

Thanks for the info. I may try this out as well.

Cheers,
Jim
Sailing on König

[Catigale]

good solid Wichard spring-hook carabiner t

The weak part of any carabiner is the little spring that keeps it closed....but you can cheaply 'safety' this with a piece of snug fitting PVC tubing that will slip over the carabiner after it latches and prevent it from opening, even if the spring fails.

[Trouts Dream]

I used to rock climb and I am going to try this with a 30 lb kettle ball and a climbing harness carabiner. This is a spring carabiner that has a sleeve that screws up to ensure the spring cannot accidently open.
This should shorten the swing so will be trying this when in the San Juans at the end of May.

[Catigale]

This is a spring carabiner that has a sleeve that screws up to ensure the spring cannot accidently open.

In pristine Canadian Fresh Water that should be ok....in salt, I would worry that will corrode up and end up stuck....(you could cut it off, or fish it off the end of the rode, as it were...

...the end of the rode... indeeed