How to Tie a Rope to an Anchor Chain

An anchor with a chain.

Tying a rope to an anchor chain is not a permanent solution--like turning an eye splice around a thimble baled around the anchor ring. It may, however, be necessary in a pinch if the anchor line has suffered rot, abrasion from embedded sand or grit, or has strand-opening kinks that were not removed before stowage. Any knot that does not readily capsize will demonstrate 80 percent of the strength of a single length of line or rope that has an eye splice turned around a thimble.

Instructions

1. Make a loop in the line, as if to start tying a bowline.

2. Pass the end of the rope through the link in the anchor chain farthest from the anchor ring. Use the largest rope that will pass through the link without binding on the line.

3. 

   Finish tying the bowline (see illustration). The bowline illustrated is a simple bowline, although a double-loop French bowline will also work. (A French bowline will require a longer length of line and may give a false sense of security; a French bowline's two loops are rarely the same length--meaning an extra bend contributes to the degeneration of the knot's holding power without adding any holding power to the knot.)

4. 

   Tie the "bitter end" of the line to the bowline's loop. Use a figure-8 knot, to prevent the bowline from loosening when the bowline is not under a strain. Slide the figure-8 knot along the loop until it reaches the top of the bowline, then pull it tight.

Tips & Warnings

• Recreational vessels that are 30 feet in length (or less) can be held by a line that supports a 90-pound pull; the standard formula for the safe working load of a line is determined by squaring the circumference of the line, then multiplying by 150. Using that formula, 1/2-inch line has a safe working load of 235 lbs. Use hard-laid nylon line; soft-laid line tends to fray. If only soft-laid line is available, use duct tape on the ends to prevent fraying. Do not use polypropylene lines, as they float and counteract the anchor.

• Nylon line, no matter how small, will "snap back" if it breaks while under strain--and may cause serious injury or death.

Resources

• Read this Article in Spanish
• Anchoring Guide