Leaving Your Boat Unattended // The Double Shackle ?

Mr Lingcod

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Mar 20, 2017
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45
Santa Barbara
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Jesse
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The Last Soviet
Going to hike a cool wash out at the islands this weekend and will be leaving the boat for about 5 hours. I 100% believe in my nylon rope, boat-length chain, and oversized danforth anchor. Works every time. But ... this isn't really about safety. This is about "calming the nerves" while leaving the boat.

The Options

- Double anchor (bow & stern): this is a huge area, so not needed to prevent swings.

- V pattern, with two hooks on the bow: this may compromise even one good hook with minor swings

- The Double Shackle: See attached photo. Basically taking off the shackle from the stern anchor system and attaching it right into the bow anchor. The redundancy and extra weight from the chain makes it seem like the 10 minute, bullet proof solution that will give me peace-of-mind.

Thoughts?

IMG_3516.JPG IMG_3517.JPG
 

ShadBurke

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Oct 28, 2005
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Shad Burke
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22' Boston Whaler Guardians
Bow and stern anchors. Adjust ride for tide situation. Make sure you 'set' the anchors really well.
 

Mr Lingcod

I've posted enough I should edit this section
Mar 20, 2017
110
45
Santa Barbara
Name
Jesse
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The Last Soviet
Bow and stern anchors. Adjust ride for tide situation. Make sure you 'set' the anchors really well.
What about a wind shift? Then you have your boat unattended with wind/chop hitting it from the side or stern.
 

ShadBurke

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Oct 28, 2005
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Shad Burke
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Wind shift shouldn't be a problem with properly set anchors of the proper size with proper chain and rode (until you reach gail situations which is a completely different conversation).

When I set my anchors, I scope them quiet well and use the motor to drag them until they catch and hold at 1,400 rpm.....
 
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sickcat

Silverback
Aug 5, 2003
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What about a wind shift? Then you have your boat unattended with wind/chop hitting it from the side or stern.
Depends a lot of where your anchoring and the conditions/potential conditions. Not a fan of 2 lines to a single anchor for something like this. Proper size rode in good condition with proper connections and you'll be fine.

Wind would really have to come up to worry much about getting hit from the side. Stern would be worse but the choice without the stern anchor is for the boat to swing 180 and that usually means you may well drag anchor, maybe into the island or maybe offshore before the anchor resets..

If your going to leave it unattended then I second a bow/stern anchor and setting those anchors well. Maybe add a cantenary (SP?) weight to the bow anchor.
 

Mr Lingcod

I've posted enough I should edit this section
Mar 20, 2017
110
45
Santa Barbara
Name
Jesse
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The Last Soviet
Depends a lot of where your anchoring and the conditions/potential conditions. Not a fan of 2 lines to a single anchor for something like this. Proper size rode in good condition with proper connections and you'll be fine.

Wind would really have to come up to worry much about getting hit from the side. Stern would be worse but the choice without the stern anchor is for the boat to swing 180 and that usually means you may well drag anchor, maybe into the island or maybe offshore before the anchor resets..

If your going to leave it unattended then I second a bow/stern anchor and setting those anchors well. Maybe add a cantenary (SP?) weight to the bow anchor.
Thank you. Advise heard. But help me understand why for "something like this" you would advise against the double shackle? When would be a good time? Why not this time?
 

sbsurfer

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Feb 19, 2010
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I'd also increase the chain length to double the boat...that should have more impact than the larger anchor. I'd also switch to a Bruce anchor for the islands and keep the danforth as a back up. Take a look at all the commercial boats in our harbor...99% have a Bruce, none have Danforth's.
 
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apogee

My name is Apogee and I am a Squidaholic
Jan 29, 2009
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Bakersfield
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Apogee..
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Boston Whaler Outrage 28 (End Game)
Bruce or Delta....Ap
 
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benrd81

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May 21, 2009
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Ben
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2660 Sailfish WAC Reellife
Loose the danforth. Delta or plow too 2-3 boat lengths worth of chain.
 
Jul 9, 2003
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Gary
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The Right Kind - 31' Cabo Express
My experience...I did a job for the Nature Conservancy at the adobe house in the middle of Santa Cruz Island. I loaded up the contractor, my crew and equipment to do the the job onto my 25' Parker and across the channel we went. I anchored up at Prisoners launched the inflatable and unloaded everything on the pier. Two jeeps were there to take us to the ranch. Before we left I made sure I had anchored in deep enough water, lots of scope and the anchor was well set, a single Bruce off the bow. I figured it was better to swing with the wind and I was sure I was out deep enough to be far away from the pier. The ranch is about 7 miles into the interior in a low lying valley, no views of the ocean. The job took all day and the whole time I was worried about the boat and if the anchor was holding. When we got back to the pier the boat was almost on the beach in about 5' of water. The wind had switched and the tide had dropped, a minus tide. I should have checked that too. Scary shit! The three strand anchor line had come unwound (swackeled) even with the swivel, but all was good. Our next trip out, I dropped off my crew and stayed on the boat catching yellowtail. A much better day. If I did it again I'd drop one of the bow and one off the stern without a doubt. Have fun!
 

MYNomad

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Dec 12, 2007
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Yes
There are lots of different opinions about anchoring. Mine are:
1) if you haven't anchored enough to have 100% confidence in your anchor system, don't leave the boat. Probably only because of the coverage amount, but my insurance policy requires that I, or a licensed captain approved in advance by my insurer, must be on board whenever the boat is anchored. In other words, they aren't willing to take the risk that my anchor won't drag (and I don't blame them).
2) Stern anchoring makes sense when you need to limit swing, but it won't stop your bow anchor from swinging (and ironically, the depending upon wind/current shift, my increase the load and therefore chance of dragging your bow anchor. And if the two drag into each other, probably both get fouled and neither holds.
3) I have never seen the stern anchor set up you are describing. Maybe it works, maybe it works well, but to me it looks like you are reducing the holding power of at least the bow anchor, and also increasing the risk of fouling it.
4) Go with all chain rode, if possible.
5) If you are going to leave the boat, consider purchasing a remote anchor alarm.
 

Keitha

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Oct 2, 2013
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Costa Mesa, CA
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KA
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18' Outrage
Look up Tandem Anchoring. it uses two anchors in series: one connected with chain to the other.
Research what type of anchor to use/avoid (avoid the danforth) with this technique and how to rig it.
 

sickcat

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Aug 5, 2003
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Thank you. Advise heard. But help me understand why for "something like this" you would advise against the double shackle? When would be a good time? Why not this time?
Only time I might consider running two rode to a single anchor would be in serious storm conditions. For anchoring up at the islands IMO two chains and rode would only hinder the anchor from setting and/or re-setting if conditions changed.

For something like you as looking at doing the shackle, chain and rode (properly sized and installed of course) will not be the point of failure. The most likely issue will be getting the anchor to hold in one spot especially if the conditions change dramatically from when it was set. To address that the right anchor, chain and rode are the key along with backing down hard while setting it. For most "local" situations I like a Bruce anchor. An anchor one size bigger than recommended and plenty of chain add some piece of mind. Easiest thing for you would be to add a length of heavier chain to the anchor and attach the existing chain to that.

Another thing is to be aware of where your anchoring in respect to what would happen if conditions changed. For example if you set the anchor close to the drop-off on a shelf that falls away steeply then if the wind changed and swung the boat around so it was over the drop-off. Now if the anchor drags it will likely pull it off the shelf with little chance of re-setting as it drags down the slope. I hope that makes sense. Quite a few times I have seen boats drifting down the island with the anchor rode hanging straight up and down. Sometimes somebody was on-board (and totally unaware) and other times there was nobody.

Again when you set the hook back down on it HARD until it sets and sticks.
 
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Mr Lingcod

I've posted enough I should edit this section
Mar 20, 2017
110
45
Santa Barbara
Name
Jesse
Boat
The Last Soviet
Only time I might consider running two rode to a single anchor would be in serious storm conditions. For anchoring up at the islands IMO two chains and rode would only hinder the anchor from setting and/or re-setting if conditions changed.

For something like you as looking at doing the shackle, chain and rode (properly sized and installed of course) will not be the point of failure. The most likely issue will be getting the anchor to hold in one spot especially if the conditions change dramatically from when it was set. To address that the right anchor, chain and rode are the key along with backing down hard while setting it. For most "local" situations I like a Bruce anchor. An anchor one size bigger than recommended and plenty of chain add some piece of mind. Easiest thing for you would be to add a length of heavier chain to the anchor and attach the existing chain to that.

Another thing is to be aware of where your anchoring in respect to what would happen if conditions changed. For example if you set the anchor close to the drop-off on a shelf that falls away steeply then if the wind changed and swung the boat around so it was over the drop-off. Now if the anchor drags it will likely pull it off the shelf with little chance of re-setting as it drags down the slope. I hope that makes sense. Quite a few times I have seen boats drifting down the island with the anchor rode hanging straight up and down. Sometimes somebody was on-board (and totally unaware) and other times there was nobody.

Again when you set the hook back down on it HARD until it sets and sticks.
Great point: the "point of failure" is not the rope snapping; it's the anchor dragging or not resetting well. So you don't need two. You just need one good one.

I'm going to take off the double shackle because I don't want to compromise the same set up that's worked flawlessly in all conditions thus far. I'll double anchor. (My takeaway is that if you really want to make sure, buy a heaver set up.) But short of doing that A) believe in your system, B) set the anchors really, really well, C, inspect visually before using, and D) buy more chain. I do overnights all the time that are longer and never have to reset. This was all about exploring "peace of mind" solutions. Thanks everyone for the wisdom. I know it's often hard-gained.
 
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4L2NA

Well-Known "Member"
Apr 14, 2012
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Newbury Park, CA
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Larry
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25' Davis RHLC, D4, FinAddict
Like others have already mentioned, the best thing you can do to increase holding power/efficiency (besides good technique) is to increase the length of the chain to 2x-3x boat length. I use 50' on my 25' boat, and we use 75' on the urchin boat. The extra weight substancially improves the holding power. Ideally, when we set the hook we like to have only the chain on the seafloor, and have the anchor line suspended in the water column, off the bottom. This may not always be possible depending on conditions, depth, etc.. It's also a good idea to have a good windlass.... or a good back (I'm too old to want to do that now...lol).

I have never tried your purposed double shackle technique, it may work in the right conditions. Personally I would rather you use the extra chain to length your bow anchor chain, less potential for foul ups with a single leg. As divers we routinely check the anchor line(s)...and you'd be amazed at what you would sometimes see despite our best efforts...even with perfect technique, sometimes Mother Nature just wants to mess with you, hahaha.

For local waters (Ventura/SB, Channel Islands), I like the Bruce anchor much better than the Danford. The Danfords seem to sail/swim when deployed. That said, I do use one when I do set a stern anchor. As others have mentioned, the double anchor (bow/stern) could be useful in a crowded anchorage (assuming others around you are anchoring in the same manner....don't be the odd one out), or perhaps in a situation where you need to keep the bow into the waves, eg waves refracting around a point. But I have been burnt in areas where the current shifted and now I need to swim against a very stiff current in a low air situation. So most of the time, it's a single bow anchor.

Conditions and technique are obviously the most important factors, but alot also depends on your particular boat, how you like to set it up and what you like to deal with. Have a great time out there, the islands are a beautiful place to be.
 
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