Burnt Store Isles Boat Club, Inc.

Offshore Anchoring Tip
Len Harris

When it comes to anchoring, some people may lead you to believe it is difficult, especially in deeper water.

To set up your anchoring position use your GPS/Chart Plotter and zoom in so the screen is showing 400 feet across and make sure you have the plotters track feature enabled. Position your boat directly above the structure you want to fish, with the boat in neutral start drifting. As you drift away from the structure the GPS/Chart Plotter tracks a course line, hopefully down wind and away from the structure. 

If you are drifting against the wind, it’s not even worth anchoring, however most of the time you will drift down wind.  Drift for at least 30 seconds to two minutes and plot your course. Follow your course back to the structure.  Using the plot as a reference extend it out upwind out to .7 nautical miles from the structure depending on how deep it is.

This should put you about 300 to 400 feet upwind of the structure then lower the anchor. When the anchor hits bottom and you drift back toward the structure, you should be in ideal position when the rode tightens.  

The rule of thumb to follow is to go three times the depth past the wreck before lowering you’re your anchor. For example, if you are in:

• 50 feet of water, go 150 feet past.
• 100 feet, go 300 feet past.
• In 150 feet, go 450 feet past.

Ensure that you have the correct type of anchor for the structure you plan to anchor over and the rule of thumb for the length of chain to hold you rode down is the length of your boat. 

Ground Tackle and Anchoring When Cruising
Tom Murphy

Ground tackle is one of the most important investment cruisers can make upon which will hang not only your home at sea but also perhaps your very lives. Persistence is 34,000 lbs dry and about 40,000 lbs wet. That is 20 tons of plastic and other materials hanging in the breeze. We prefer to anchor whenever we can so we have given considerable thought to our ground tackle and anchoring techniques.

Persistence's main anchor rode is all chain. In fact, Persistence carries 400 ft of BBB chain (a leftover from our blue water days up north). Our chain is ¼ inch which is a bit light by any standard but was the manufacturer's recommended chain for the vessel when new. Persistence also carries two other combination chain and nylon rodes, each of which is 40 ft of chain and 300 ft of 5/8 twisted nylon. Persistence carries two anchors on two rollers on the bow. One anchor is a 44 lb Delta Fast Set and the other is a 44 lb Horizon Claw. We also carry a 60 lb Danforth fluke for heavy weather. We are tempted to replace the Danforth with an Fortress FX-55 to reduce weight and make handling and stowing the anchor easier. Any anchor can be connected to the chain rode and used as the primary anchor depending upon bottom conditions. In Southwest Florida we use the Delta Fast Set as our primary working anchor. The ability to change anchors and deploy multiple anchors when needed gives us the confidence that we can safely anchor anywhere, anytime.

We use a ½ in twisted nylon bridle with a chain hook to take the load off the windlass, keep the boat centered from sailing in the wind. . The bridle is essentially a 15' to 20' line with loops on each end to fit over the forward cleats. The chain hook is positioned in the center of the line and is used to hook the chain rode and then when the chain is let out further the nylon takes the load. Idealy, the loose chain behind the chain grabber should droop a few feet to give way when the bridle stretches. The ½ inch nylon acts as a shock absorber and stretch and contract with the movement of the boat.

We rarely deploy two or more anchors except in heavy weather. The hassle of wrapped anchor rodes with shifting winds or current is better solved, in our opinion, with a larger anchor and more scope. We typically deploy 7:1 scope or more with our chain rode and 10:1 with our Nylon rodes. Be sure to mark the rodes so that you can determine the scope. On our chain rode I use nylon tie-wraps to indicate the length. We use one tie-wrap for each 10 ft of length and change colors every 50 ft. We use the tags bought at West Marine to mark the nylon rodes. When we do use two or more rodes we will always down-rig a 10-12 lb mushroom anchor to take a slack nylon rode to the bottom to prevent fouling on the running gear. The down-rig is essentially a polypropylene line with a snap hook attached to a mushroom anchor. The snap hook, with anchor attached, slides down the nylon rode to the bottom. In our area you only need 20 -30 ft of polypropylene line to get to the bottom. As the boat swings in the wind or current it will alternately place a load on each anchor. A slack chain rode will drop straight down due to the weight of the chain. A slack nylon rode with the down-rig will drop vertically and avoid fouling on the running gear. The mushroom anchor also doubles as our dingy anchor. The down-rig also provides another benefit when under load. The weight of the mushroom anchor will lower the pull angle on the anchor and potentially contribute to a better bite.

For more anchoring information check out: www.boatus.com/boattech/anchorin.htm

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