What You Should Know About Boat Anchors, Anchor Winches, Anchor Chains And Ropes?
Boat anchors come in many shapes and sizes. Various boat anchors include Grapnel Anchors, Northhill Anchors (used by sea planes), Plough Anchors, Fluke or Danforth Anchors, Bruce or Claw Anchors, or Herreshoff Anchors. Each anchor has a specific purpose and use.
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Grapnel anchors usually have 4 tines. It is very easy to set as one of the tines usually will catch. These anchors usually can hold well in sand, clay, or mud.
Plough anchors are usually the most common anchors by pleasure craft boaters. It is an acceptable anchor for most bottoms, however it is not always the perfect anchor. It is called a plough anchor because it looks like a farm plough.
Fluke or Danforth anchors are another very common anchor for pleasure craft use. These anchors do have a hard time setting in kelp or weeds and are not always ideal for rocky or hard sand bottoms. It is, however a popular anchor because of its compact size and lightweight.
Bruce or Claw Anchors have become very popular among more and more boaters because they are very easy to set and tend to not break free. These anchors are very popular in ocean environments, but do have some problems being set in a grass or weedy bottom. These anchors are generally oversized.
There are other types of anchors to consider including the Spade, Mushroom, Deadweight, Mud, Screw, Navy, Bulwagga, or Wasi anchors.
Typically, you will set an anchor at a 7:1 scope. This means for every 10 feet of depth you will use 70 feet of anchor line. (If your anchor line is all chain you may use 5:1). Measurements from the floor should be done at high tide. The general rule of thumb is the more scope the better.
Anchor winches should take into consideration the vessel size, displacement, windage, anchor size, and rode selection. Vertical windlasses make up the majority of anchor winch sales. Horizontal windlasses are mounted completely above deck (Vertical can be mounted below deck). For safety, you can calculate ground tackle which is the weight of the anchor plus the weight of the chain plus the weight of the rope. Take this total weight and multiple times 3 and the final pound total is what you should use for a windlass. It is always best to error on the side of having too much rather than not enough power.
Typically, chains are determined by the size of boat you have and weather the boat is light, medium, or a heavy weight.
Boats 23-27 should use 3/16 chain and 3/8 rope.
Boats 28-32 should use 1/4 chain and 7/16 rope.
Boats 32-36 should use 1/4 chain and 1/2 rope.
Boats 37-40 should use 5/16 chain and 9/16 rope.
Boats 41-45 should use 5/16 chain and 5/8 rope.
Boats 46-54 should use 3/8 chain and 3/4 rope.