Stern anchor

[tobnpr]

Stern anchoring is fine, and usually mandatory, when anchoring stern-to a beach or sandbar where you can't let wind/tide dictate the lay of the boat, as a "lunch hook".

However, don't confuse the use of a stern anchor in fair-weather conditions with anchoring in open water- especially if there is a threat of heavy weather.

Anchors are not designed to hold under lateral loads. Anchored with the wind/current on the beam can result in the anchor(s) pulling loose. If the bow anchor pulls, you could find yourself anchored by the stern- a potentially dangerous scenario.

Anchoring in open water overnight, especially in tighter quarters where an anchor dislodging could be disastrous, is best done with two anchors set properly off the bow.

 

[kg4vgh]

I use two anchors also.....usually when I have 1 or 2 other boats along side and we are watching the fireworks.....keeps the stern pointed in the right direction....for the ohhh and ahhhhsss......would never anchor from the stern solely though....

 

[billnpat]

I use two anchors also.....usually when I have 1 or 2 other boats along side and we are watching the fireworks.....keeps the stern pointed in the right direction....for the ohhh and ahhhhsss......would never anchor from the stern solely though....

Agree,

Never solely from the stern....:smt001

 

[HUMPH]

Anchoring in open water overnight, especially in tighter quarters where an anchor dislodging could be disastrous, is best done with two anchors set properly off the bow.

+1 :thumbsup: I agree there. When I overnight I want the security of the second anchor off the bow. The river currents are really fast and I don't want to be sideways to it or having it push on the stern!

 

[JVM225]

I keep an extra anchor on the boat for emergencies, and the rare occasion that I use a stern anchor.
It's the same size as my main anchor. I can't remember off hand, maybe 13 lbs or so? Your 31 should use the same size as my 30. I can check it and let you know if you want.
I have about 6' of chain on it, and probably 100' of line.
Like you, I boat on the south shore. Although I have about 200' of line and a dozen feet of chain on my main bow anchor, I keep less on my extra anchor because of storage limitations. In the very shallow water around here, the 100' is more than enough for emergencies, etc..
I don't use a bow and stern anchor at the same time because there really isn't any need to around here, and you want to swing the same way as the boats around you in the coves because it can get tight in them.
I mostly use the stern anchor at either Hemlock Cove or Zachs Bay on weekdays when there aren't really any other boats around, and we are just stopping for a coule of hours or so for lunch or something.
I kind of like it because it means you get the breeze in the cockpit, plus it's easy to keep an eye on it.
The other problem with using a stern anchor when it gets crowded around here is that nobody is looking for it. Too much of a chance of a mishap, or another boat running over it because they don't see it.

 

[billnpat]

I keep an extra anchor on the boat for emergencies, and the rare occasion that I use a stern anchor.
It's the same size as my main anchor. I can't remember off hand, maybe 13 lbs or so? Your 31 should use the same size as my 30. I can check it and let you know if you want.
I have about 6' of chain on it, and probably 100' of line.
Like you, I boat on the south shore. Although I have about 200' of line and a dozen feet of chain on my main bow anchor, I keep less on my extra anchor because of storage limitations. In the very shallow water around here, the 100' is more than enough for emergencies, etc..
I don't use a bow and stern anchor at the same time because there really isn't any need to around here, and you want to swing the same way as the boats around you in the coves because it can get tight in them.
I mostly use the stern anchor at either Hemlock Cove or Zachs Bay on weekdays when there aren't relly any other boats around, and we are just stopping for a coule of hours or so for lunch or something.
I kind of like it because it means you get the breeze in the cockpit, plus it's easy to keep on eye on it.
The other problem with using a stern anchor when it gets crowded around here is that nobody is looking for it. Too much of a chance of a mishap, or another boat running over it because they don't see it.

Thanks....What marina are you with??...we're at M.M. SS3 lindenhurst.....

 

[JVM225]

I'm a little bit west of you on the Venice (or Grand) Canal on the Copiague/Lindenhurst border. I have a little piece of property on the canal where we keep the boat.
We just got the property last season and moved the boat there. Prior to that, it was further up your canal at Karl Tank Boatyard.

 

[billnpat]

I'm a little bit west of you on the Venice (or Grand) Canal on the Copiague/Lindenhurst border. I have a little piece of property on the canal where we keep the boat.
We just got the property last season and moved the boat there. Prior to that, it was further up your canal at Karl Tank Boatyard.

We're moving to
Great Neck Creek next year or two
Condo with a slip...being built now in Copiague....:thumbsup:

 

[comsnark]

Stern anchoring is fine, and usually mandatory, when anchoring stern-to a beach or sandbar where you can't let wind/tide dictate the lay of the boat, as a "lunch hook".

However, don't confuse the use of a stern anchor in fair-weather conditions with anchoring in open water- especially if there is a threat of heavy weather.

Anchors are not designed to hold under lateral loads. Anchored with the wind/current on the beam can result in the anchor(s) pulling loose. If the bow anchor pulls, you could find yourself anchored by the stern- a potentially dangerous scenario.

Anchoring in open water overnight, especially in tighter quarters where an anchor dislodging could be disastrous, is best done with two anchors set properly off the bow.

What he said.

Huge difference when backed up to the beach for a sunny afternoon, vs overnighting where thunderstorms can pop up or winds can change.

Most of my anchoring experience is the overnight type, where you factor in thunderstorms and wind changes.

If you think a storm can come up, you definately do NOT want to be in a raft up, where a single dragged anchor can jeopordize multiple boats (and where a single anchor is more likely to come loose!)

You also want the boat to be able to swing into the wind, where it can take waves/wind easier. If you actually swing 180 degrees due to changing conditions. . then resetting the anchor (or watching it carefully) may not be a bad idea.

Also, most boats I have seen in open water use a single anchor, and thus rotate with the wind. You do NOT want to be the ONLY boat that is not rotating with the wind. You might end up closer to your neighbors than you expect. If you all rotate. . .then you all maintain your distances.

Fireworks is a special case where I boat. Everyone packs tightly together. Morons outnumber flies. Too many people anchored too close, with inadequate scope. On July 4th, I watch the neighboring anchored boats like a hawk. In a friendly "mind the elbows, bud" sort of way.

 

[tdschafer]

Hey Bill, I use the stern anchor when I anchor out by Davis Park. You will find many boats crowded together and if you don't double anchor you will swing out and hit the other boats! Todd

 

[Four Suns]

I think there are two different discussions here. The first is defining the "swing" as being oriented so your boat is downstream of the wind direction (or tide) and assumes all the boats anchored around you essentially are stable and stay that way. The second discussion, I think, is when the boat is swinging back and forth like a big pendulum at anchor... that is very different than being stable downwind of the anchor. If your boat is swinging like a pendulum, you need to stop it as it can break your anchor free from the bottom, bend your anchor and have you hit other boats that are not swinging like a pendulum (or swinging like a pendulum but at a different frequency). A stern anchor can help with the pendulum motion but it then prevents your boat from swinging to be oriented with the wind/tide like the other boats or objects around you.

The scope being increased will not stop the pendulum effect. I discussed in another post but I've copied it here:

The boat swinging like a pendulum on the hook is caused by the boat "sailing" upwind. I drew a little diagram on my Mac here for you:

The turbulence around the boat will orient the boat with a side to the wind at some point which will begin a process where the boat will literally sail upwind until the anchor line pulls the nose over into the wind enough and then the boat rotates and sails back the other direction basically repeating the process over and over like a big pendulum on a grandfather clock. If you have a bridge boat, the problem is worse. If you have an aerodynamic body like a sailboat, the problem is far worse.

The fix is to use an anchor snubber or anchor bridal where it hooks on a side cleat up by the bow:

When the boat tries to rotate to start sailing upwind, the force is transferred to the side cleat to rotate the boat back into the wind so it won't sail.

I didn't draw this picture but this is what it looks like:

You can buy them... or make one.. I made mine...

A boat swinging in the wind like this can introduce several hundred pounds of additional force on the anchor (and not in-line with the anchor) and break just about any anchor free if the wind is strong enough and the boat is working in perfect harmony. Also, the longer you make the anchor rode, the worse the swinging becomes.

Another option, which is essentially shortening the rode but keeping the anchor line at the correct angle to the sea floor is to put anchor rode weights on the rode itself. I've never done that but know sailors that do... That also helps the swinging.

I have an all chain rode and have a horrible swinging problem if I don't use a snubber on the front. One time I ducked into a cove to avoid a squall with 60 knot winds in it and the boat was swinging so bad I almost went into a sea wall after dragging probably 500-600 feet. Some boats did hit the wall... I was lucky that day. I didn't have time to put the bridal on... and something about holding on the front of the rail with an anchor hitting ground and lightning all over the place made me jumpy.

If you have a rode made from rope, you'll have to figure out how to apply the same concept. You could probably use a small board with a cam cleat to hold the anchor rode (in place of the stainless grab hook in the bridal picture above) and then have an eye on the board to hook the triangular rope bridal to ...

Just a thought...

I don't know why Chapmans doesn't cover this very well... It's a big problem IMO.

 

[chuck1]

Anchoring in open water overnight, especially in tighter quarters where an anchor dislodging could be disastrous, is best done with two anchors set properly off the bow.

Are you referring to a Bahamian type anchoring setup?

 

[tdschafer]

Four Sons,
That was a very well put together presentation. Thanks for the education. I've seen those bridals before but only when one boat was towing another. I never thought of it in an anchoring application. Thanks again! Todd

 

[billnpat]

Four Sons,
That was a very well put together presentation. Thanks for the education. I've seen those bridals before but only when one boat was towing another. I never thought of it in an anchoring application. Thanks again! Todd

+2 THANK YOU FOUR SONS:smt001

 

[Skuza]

Jesus Gary! Once again demonstrating your worth so we continue to put up with your sarcasm! HA!
Seriously nice write up and explanation of the principles at work creating the discussed situation. Never thought about the side to side motion dislodging the anchor or causing a slow drag.

 

[chumbley]

Nice summary Gary!