Tuesday, 17 May 2016

Ground Tackle & Anchoring Safely



If you spend any time reading the sailing community forums you’ll quickly come to realize that there are many topics, which seem to polarize the audience of contributors (or perhaps those sensible enough to avoid trying to convince others just stay out of it).  One of the most contentious topics is ground tackle – this is also one of those areas where it doesn’t matter who is right – what matters is what works for you and what you trust to protect your home. 

The only question that matters is; “do you trust your ground tackle?”

We didn’t, which was a problem. 

In the period between July 2015 and January 2016 we cruised and anchored with the ground tackle that had been in place on our boat when we bought her.  As you may have read on the “Boat” page, Maple is an ex-charter catamaran from the Sunsail fleet.  When we bought her we were told that she had 50 meters of chain on board which was connected to a 35kg  25kg Delta plow anchor.  We never dragged, but we were never really trusted our ground tackle.  There were a couple of things that made us feel this way.

1)   The Delta very rarely set in the first try.  We would carefully drop enough anchor and chain to reach the bottom based on our depth sounder and an eyeball measurement of chain (it was not marked).  We would then slowly back up, laying out more chain until we thought we had reached a 5:1 scope, at which time we would lock the chain off and reverse on our anchor.  Mostly this resulted in the anchor dragging along the bottom so we’d bring it up and try again.  On the 3rd or 4th try it would usually stick.

To be fair, we were often anchoring on weedy bottoms which can be hard for any anchor to penetrate, but we didn’t see many others struggling as much.  Perhaps they were not being careful about their anchoring, but regardless of the reason, the end result for us was a lack of trust in our hook.

2)   The chain seemed under-sized.  The boat came with 8mm G3 chain, but it seemed rather small for the boat.  Chances are the boat left the manufacturer with an 8mm gypsy on the windlass which is what determined the chain size.  If this was the case, I didn’t have any real reason to believe that it wasn’t big enough but it felt smaller than it should be.

3)   In Italy I had a chance to measure the chain and attempt to mark it – in doing this I made the discovery that we did not have 50M of chain, we had a mere 40M, including the length that extended into the chain locker where it attached to the boat.  Assuming we continued to put out 5:1 scope we would be limited to anchoring in 8M or less and there aren’t many anchorages with that kind of depth in Greece or Turkey.  The end result is our ground tackle would have us putting out less than ideal scope making us less secure than we’d like.  This is probably the best (and main reason) we didn’t really trust our ground tackle.

4)   The ground tackle was not really set up properly. 

The bitter end of the chain was shackled to the boat and the shackle was undersized and rusted shu t.  Not only would it not hold if a load was placed on it, we would struggle to cut it free if we had to leave an anchorage in a hurry.

The shackle holding the anchor to the chain was undersized and rusted.  This was the weakest link in our ground tackle and meant that the working strength of the entire system was even less than the strength of the 8mm chain that I already felt was under sized.


No – it was a given that we would be getting new ground tackle.  Anchors and chain are an expensive proposition, but well worth the expense given the importance of being trusting your vessel to stay put when it is most vulnerable.

3 comments:

  1. Known by some as the "Delta Fast Drag". We are happy with our Rocna. Go all chain and you'll never go back to line. Only 40m total??? No wonder you have been uncomfortable. We have 300 ft, and have often used 200'.

    David
    sailing-pelagia.blogspot.ca

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    1. Fast drag - I like that. It was certainly our experience. It seemed the Delta would only set if we sat for 5-10 minutes and let it rest on the bottom before pulling back on it...

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  2. Second on the rocna, it's been great for us too.

    200'/60M chain is a useful minimum, but do back it up with another 200'/60m of rope (spliced on) in case you need to anchor really deep sometime. Octoplait is best for the line, as it does not hockle or twist when stored.


    Also attach the bitter end with many turns of a light line to get the required strength. That way it's easier to cut if need be.

    I suggest you look for a chain stopper if you don't have one. Bolted to the deck between the anchor and the windlass, it takes the strain should your snubber fail, preventing the heavy shock load from damaging the windlass. Windlass are not designed to take the shock load an anchor can impose.

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