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Anchor doesn't hold?

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  • Anchor doesn't hold?

    I have trouble getting my anchor to hold on sand, clay, and mud bottoms of Lake Erie. I'm never in water deeper than 50'. I have at least 150' of anchor line. Someone told me that I might need a longer piece of chain between the anchor and nylon rope. Does this sound right? The current chain is a couple feet long. Could I just need a bigger anchor? I have a 17' boat and the anchor is the Danforth type.


  • #2
    Re: Anchor doesn't hold?

    I would use at least a 6'- 8' length of chain (5/16'-3/8"). The purpose is; the weight of the chain gets the shaft of the anchor more parallel to the ground; it digs in better that way. Your scope 150'(rode length) divided by 50'(water depth) is 3/1 about minimum to hold with a little wind. Keep in mind a 7/1 scope is what you'ld want in a storm. With 150'(7/1 scope)of rode out you'ld get a grip in 21' of water or so, too shallow in my opinion (in a storm); you'll be in the surf. I would want at least 250' - 300' of 3/8' rode on Lake Erie for your size boat. I like a storm anchor, which is defined as one size bigger than you need. The trick is; a Danforth style anchor will dig into the bottoms you discribe until it HOLDS; if it's working right and the right size. It literally buries itself till it holds. Remember an anchor is the last resort from keeping you off the rocks when the motor fails. Often overlooked. Hope this helps.

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    • #3
      Re: Anchor doesn't hold?

      Mumblerone said it all. A Danforth anchor will actually sail in a current if you don't have enough chain on it. I use 10' for my 17' boat and it always digs in. This is in Gulf with about a 4 knot current.

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      • #4
        Re: Anchor doesn't hold?

        Thanks for the tips! I'm getting ready to put it up for the winter but I'll be sure to get a longer chain and rope on it next spring.

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        • #5
          Re: Anchor doesn't hold?

          Hi Phil,Another point to check on a danforth is that there is enough play/swivel/swing between the shaft and the "blades" of the anchor. You should have at least 45 degrees plus swing each way. I had the same problem with mine and had to modify the anchor with a cutting torch to allow enough swing. Problem solved.

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          • #6
            Re: Anchor doesn't hold?

            i think the recommendation to add some chain will do the trick. you shouldn't need much more line. the navy always anchors with chain 5-7 times the depth of the water, but relies on the chain holding the ship (anchor doesn't actually hold the ship). With more chain you should be able to get the anchor to dig and hold for you.
            2002 Wellcraft 290 Coastal
            Twin 2002 Yamaha F225s

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            • #7
              Re: Anchor doesn't hold?

              Mattttt25...could you expand on the "anchor not holding the ship?" Should we not use anchors but only chain?

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              • #8
                Re: Anchor doesn't hold?

                With all due respect matt, the amount of chain practical on a small craft (+- 6 -8 ft) will not make any difference to the anchor holding. When the rope/chain/anchor shaft combination is pulled tight, a straight line is formed from the bow to the bottom. The angle depends on the amount of rope let out, usually 3-5 ft per 1ft depth. You have to first establish if the anchor is biting and then pulling free or whether it is dragging/slipping without digging in. If it is the first scenario, the anchor is to small for the boat, if it is the second scenario, more rope or changing the angle of the blades with regards to the bottom will help.The only reason big ships use chain is that it is not practical to use rope for such a heavy anchor.

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                • #9
                  Re: Anchor doesn't hold?

                  friends- won't comment on whether the guy needs more line or not. in my opinion, if he has the right size anchor, 3 times depth of water should be plenty of line.as for large ships (navy), no, the anchor does not set (or hook) like we all understand in small craft boating. how would you unset a 40,000 lb anchor? we anchor with chain 5-7 times the depth of water and rely on the weight of that chain to hold the ship. the anchor only comes into play under extreme weather conditions and when there is enough force (wind, current) to drag the anchor. that is why we use chain.
                  2002 Wellcraft 290 Coastal
                  Twin 2002 Yamaha F225s

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                  • #10
                    Re: Anchor doesn't hold?

                    I've been trying to find a picture of the anchor most commonly used here on the Columbia and Willamette Rivers, but apparently they're local products: none of the national vendors carry anything like them. Essentially, they're an iron "T" with a fluke sticking out the ends of the "T" @ (sort of) right angles to the anchor shaft. They come in 2 models: heavy and heavier. (we use anchor pullers, also locally made, to hump them off the bottom). They're popular here because we're attempting to hold our 18-30' boats against 4-10+ mph currents while fishing.The point is: 1) Danforth anchors don't work, at least here; and, 2) whatever you use, use at least 6' of heavy chain. The chain allows even a mediocre anchor the opportunity to dig in.You might try one of the more effective (and expensive) plow anchors. I recall seeing a test on anchors when like-looking anchors worked with varying success. So the brand does make a difference.

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                    • #11
                      Re: Anchor doesn't hold?

                      PhilWe need a little more information to help you. First what size and type boat do you have?? How heavy is your anchore?? Does is break loose only durning strong currents or wind and chopp?? A standard 8 lb Danforth should hold a boat in the 16 to 24 foot range in non storm conditions.You need at least a 3 to 1 scope in calm conditions. For scope it the depth of the water plus the height above the water times 3. 50 foot of water plus 4 feet to bow or 54 feet times 3 = at lease 162 feet. If you do not have enough rode the shank of the anchor will pull up off the bottom and fluke will come up out of mud or sand as well. Chain will help hold the shank down in calm low current conditions but as wind and current picks up even the chain will pull straight, Only more line or rode will help here.There is a big difference in anchors. My Favorite is the Fortress. It is a light weight Aluminum anchor and a 4 lb will hold better than most 8 lb steel. You can set the Flukes angle at 32 degrees or for mud and sand at 45 degrees. The 45 degrees really helps with a short scope.I carry two anchore A Fortress FX-7 with 5 feet of chain and 250 feet of line, and a 8 lb standard Danforth with 5 feet of chain and 300 feet of line. I only use the Fortress because is is so much nicer. The wife can pull it easy but it holds so good. Since it is lighter when setting must not back up too fast until it hits the bottom. When it hits it sharp flukes dig in and hold.One last thing where we fish for Sturgeon always see a lot of boats not holding bottom and drifting by. Every one the anchore is straight down to 45 degrees where I know the anchore flukes are pointing up out of the mud not down into the mud.Next time you have trouble tie on another line or move to shallower water and see if that your problem. Good luck and save a few fish for us.
                      Have some fun and enjoy the Great Outdoors.
                      Love to fish out of Bodega Bay, California.

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                      • #12
                        Re: Anchor doesn't hold?

                        Phil,I add 4’ – 5’ more feet of chain to your anchor and you should be fine. I have one of those Fortress anchors that Boatist was talking about (best anchor I’ve ever used) and I was having trouble with mine holding. I added 4’ of chain to the already 4’ of chain that I had on it and it holds in anything now.

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                        • #13
                          Re: Anchor doesn't hold?

                          CapnMike - This is the type of system you refer to? Not a great picture but it shows the T anchor and float for pulling the anchor up. If the float / puller system is only local to us - then everyone else must either A. have a different type mechanical puller, orB. not need a formal health club membership.

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                          • #14
                            Re: Anchor doesn't hold?

                            mattttt25I thought twice about even commenting on this, but I'm hard headed.We have a Navy ship here in our shipyard today. It is a guided missle cruiser. The anchor weight is 8,000 pounds. Each of the anchor chain links weigh about 100 pounds each.The reason that a long length of rode is used is basically the same reason others have told the original poster to use a longer piece of chain. The chain next to the anchor helps the anchor dig in.While 100 pound links sounds heavy, there is no way the chain alone will keep this 425' long ship grounded.The way Navy ships recover 40,000 pound anchors (which may be typical for an aircraft carrier) is with a huge winch!!.(Not my intention to hurt anyones feelings).Regards to all,Gold Bear

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                            • #15
                              Re: Anchor doesn't hold?

                              gold bear- as a former deck officer on a 570' naval vessel, i actually have some experience and knowledge on this subject (unlike most of the topics on this board, where i'm absolutely clueless). i will retract my comment that the anchor does not hold the ship, but stress that we do not 'set' the anchor like i do with my 20' fishing boat. the heavy weight of the anchor assists in dropping or 'placing' the anchor in the desired anchorage. chain is then paid out to form a heap of heavy steel. we then slowly back down and pay out 5-7 times the depth of water in chain. at 100lbs a link, the weight builds quickly. in that sense, the weight of the chain does hold the ship. under extreme storm conditions, the scope of chain may extend and possibly pull on the anchor, causing it to drag, but trust me, we are already dropping the second anchor before that occurs. i'll stick to my guns that the large weight of the chain holds the ship, and that the anchor is never actually 'set'. hope that's clearer, although it doesn't help the original poster much. sorry-
                              2002 Wellcraft 290 Coastal
                              Twin 2002 Yamaha F225s

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