how much weight should an anchor be to moore a 5,000 lb boat 21 feet long and how long should the chain be?

Answer 1

Anchor should be at LEAST 20 pounds (Danforth, CQR) Fortress anchors are EXPENSIVE and have a nasty habit of not being able to penetrate through weeds. 30 feet of 3'8" chain and 300' of 5/8" three strand nylon rope oughta do the trick. An all-chain rode of that length is incredibly heavy.

Answer 2

We've all seen those tables 'for a boat this size use this anchor, for a storm use one size bigger'. Your correspondent doesn't know where they get those figures; I got the below from the American Boat and Yacht Council. ABYC is a group of very serious engineers and architects. Their standards are the standards of the industry and are accepted by Lloyds and the U. S. Coast Guard amongst others. The data below was extracted from tests done to figure load on cleats, and in giving permission to use it in my book "A Cruisers Guide to Hurricane Survival', ABYC was quite emphatic that is all it is, load on a line on a cleat for a given wind speed. If a skipper is to assume that a load on a cleat is the same load as what's on the other end of the line (like an anchor), then that is the skippers assumption and not ABYC's.
Having said all that here's the poop:


Table 1
Design loads for sizing deck hardware

Boat Dimensions in ft Horizontal load on boat in pounds
Length Beam to 15 knots to 30 knots
power sail
10 5 4 40 160
15 6 5 60 250
20 8 7 90 360
25 9 8 125 490
30 11 9 175 700
35 13 10 225 900
40 14 11 300 1200
50 16 13 400 1600


A mooring implies a permamently down in the bottom, not hauled up all the time anchor, and something that will unquestionably handle a good strong blow.....so for your boat, a 20-35 pound Danforth/Bruce type; 3/8th chain three times the depth of the water, and 1/2 or 5/8 nylon three to five times the depth of the water...

Answer 3

Fortress Anchor Sizing

Answer 4

When you go to the marine store, the anchors tell you what size boat they should be used for. As for the chain, usually around 2-3 feet is the norm.

Answer 5

WOW don,t that!!! just get a book from the coast guard it will give the weights of anchors . rode size and chain its free i sure hope the first answer was a joke

Answer 6

30 to 50 feet of chain attached to the anchor itself, then anchor rope equal to at least three times the anticipated depth of water... and an anchor buoy... :-)

Answer 7

Type of anchor and seabed or bottom conditions and weather or current will all factor into what you'll need. Any local marine supply house will be able to explain what to get and why.

Answer 8

Foot Long Sub

Answer 9

Anchors don't have to be heavy to work. Mine is a FX7, it weighs under 4lbs. Its rated for a 21ft. I would go to west marine and find out what you need. You don't have to buy anything.

Answer 10

check out in stability n anchors n its maintenece book dont go for our answers or psc will catch u......