anchoring and marlinspike seamanship 231
Anchor Chain Size
Recommendations
Boat Length Chain Diameter
25–30 feet 1/4 ̋
30–35 feet 5/16 ̋
35–40 feet 3/8 ̋
40–45 feet 7/16 ̋
45–50 feet 1/2 ̋Shackle Choices
Use only galvanized steel shackles. Stay away from stainless steel shackles—their
pins have a nasty habit of backing out when subjected to shock loads. Stainless
deteriorates in salt water when immersed for extended periods. Shackles should
be a size larger than the chain you use. For example, if you are using^1 / 4 -inch chain,
purchase^5 / 16 -inch shackles.
ROPE SELECTION, CORDAGE CARE,
AND CHAFING GEAR
When choosing anchor rope for your anchor rode, use nylon because of its
ability to stretch up to 25% under load and recover without damage. Choose
either three-strand or double-braid cordage.
A^5 / 8 -inch galvanized steel shackle shown with the pin out and the pin in.