Anchor Types, Rode and "Ground Tackle"
by Captain Tom Martin
There are three main types of anchors: the Plow, Danforth and Mushroom. Each has many variations which appear in many shapes and forms. The anchor rode, which is a combination of chain and rope, is used to lower an anchor. The rode has vastly improved from the original twisted vines and hemp to the modern version made of three strand twisted nylon that is both chafe resistant, shock absorbent and possess a high tensile load capacity.
Each anchor is designed to work in as many bottoms as possible yet often they don't. Several designs have proven dangerous is some situations. A combination of the right anchor, a proper amount of chain and the right diameter rope will give you a generally dependable ground tackle for most situations.
DO's and DON'Ts of Anchoring Techniques
Just like trying to use the wrong tool for the job, using the wrong anchor will cause problems inevitably. Avoid anchors with sliding rings. Designed for easy removal, they are easily dragged.
Avoid the "lunch hook" concept, usually any anchor too small to normally use but saved for brief lunch stops. By definition it is too small to use.
If you're running low on cash when equipping your boat, don't cut corners on ground tackle. It is often the last resort when everything else fails.
Any anchor must be connected to the boat by chain or rope or a combination of both. The chain does two jobs with its weight. First, it will keep the anchor shank pointed correctly helping the flukes dig in better. Secondly, the weight of the chain functions similar to the anchor to keep the boat in place. These are called "catenary": the deep curve in the anchor chain that keeps the flukes digging in and the natural elasticity of the sea lifting the chain and lowering it.
The vessel on the left has poor "catenary" with its anchor
line while the vessel on the right has good "catenary."
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Each boat and anchoring gear (ground tackle) must be set up for the size of the boat and its' intended use. Weight, size, quantity of chain, diameter and length of anchor rope are all to be considered. Most boat stores have anchor comparison charts listing boat length and anchor types and specifications for the ground tackle.
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Anchor Types and Their Purpose
The Danforth anchor and its many imitators are some of the more versatile anchors available. Danforth anchors fold flat for storage and are available for both large and small boats. The danforth type holds well in sand, mud and hard bottoms. In hard bottoms the arm will point the fluke into the bottom helping it dig in.
In grass, if it doesn't sink right in it will end up as a ball of grass and drag. There are aluminum versions that are high strength, light weight and guaranteed for life. Several manufactures offer high tensile variations and some that bolt together so they can be stored in a bag in a smaller space. Neither current or wind changes are a threat since the Danforth type can reset itself. Breaking lose a fully set Danforth can be a challenge but with practice it is usually a straight forward task.
Plow or Plough is understandably simple solution some farmer turned sailor must have adapted. The plow digs in deeper the more it is pulled and does reset itself on wind and current changes. Grass, mud and sand are all within a plows application. Hard bottoms have them laying on their sides at times.
Breaking a plow lose is easy once directly over it they will come right out. Plow variations usually are based on whether the shank is connected by a pivot with the fluke. The non-pivoting "Bruce," "Delta," "Claw" and many others have excellent holding abilities in most bottoms yet storage is a problem unless you have a bow anchor holder on your boat.
The Mushroom anchor depends on its weight in short term anchoring rather than its digging in capacity. Therefore it is generally use as a small craft anchor for brief periods and not left unattended. Yet some types of mushroom anchors once they allowed to burrow in, are use for mooring anchors. It takes awhile but once dug in they are near impossible to pull out and have to be dug out by divers with shovels.
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