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    When to use an Anchor Bridle

    I have a 1991 4588 with the Miur Couger windlass on the bow pulpit. In response to some of the posts on here I made an anchor bridle from 3/4 3-strand with two 15' legs spliced to a 5' pendent. I put dock line type rubber shock-absorbers in each of the legs. There is a Mantus chain hook on the end of the pendant. I've only used it twice and it works well, but it's a bit of a PIA to deploy. We carry a plow anchor with 150' of 5/16th chain followed by 150' of nylon 5/8 3 strand rode.

    My question is "When is it necessary to use a bridle on a 4588 with the Miur Couger windlass?" How much wind or current can that windlass handle? For overnight, I'd naturally use the bridle, but for calm conditions, is it really necessary? I attach the bridle to the two forward cleats and slacken the chain.

    There has been some discussion on here about always using a bridle when anchoring because the bow pulpit acts as a lever and will loosen the attachment point to the boat, and others have said the windlass isn't very strong or is poorly mounted. So, when is it advisable to use it?
    1991 4588
    SE Michigan

    #2
    I always use it for overnight. But not for day/lunch hooks.

    it also depends on how tight your anchorage is. Using a bridal lowered to the waterline is 5 ft, so your scope can be less and allow to anchor in a tighter space
    Pat
    Paragon
    1999 4788

    Comment


      #3
      I made pretty much the same bridle you described.

      I use ours depending on the depth, currents, and length oif time i plan ion being anchor'd.

      for example if I drop the hook in a calm bay with a water depth of 75' and no current with the intention of taking the dogs to shore then no bridle. I won't even set the anchor in this case.

      If I am in 200 feet of water and anchor to fish, out comes the bridle because of the forces on the bow roller.

      Overnight I always use the bridle and put out enough scope to weather a blow.

      KEVIN SANDERS
      4788 LISAS WAY - SEWARD ALASKA
      www.transferswitch4less.com

      Whats the weather like on our boat
      https://www.weatherlink.com/embeddab...59665f4e4/wide


      Where are we right now? https://maps.findmespot.com/s/36S4

      Comment


        #4
        As others above share overnight for sure…and depends on how long and where for short drops (ie fishing or diving depends on depth and current and wind for us
        Mark
        USCG OUPV
        1990 4588
        Carlsbad, CA

        Comment


          #5
          Like some above, I always use the bridle for overnight, it lowers the scope and that provides better hook, and can allow for less rode in some situations. In light conditions During a day stop I may not use it, but even then I often do.

          I use all chain rode, so the bridle makes a significant difference in noise inside the boat and is far less stress on the ground tackle, windlass and other hardware. As you indicate you are half nylon rode that does absorb some of the shock, but it still can result in a steep scope in particular in shallower tight anchorage.

          when we first started using the bridle we still had the pulpit on the boat and that does make it a PITA. Like some other 4788, I removed the pulpit and it is far easier now. Also a lot easier to clean mud off the anchor.

          When I removed the pulpit it made the well known Muir chain hop issue worse and I eventually went to a Lewmar vertical windlass and added a separate chain lock. The chain lock is through bolted to the foredeck with a stainless back plate this completely unloads the windlass when set and transfers the load direct into the boat. The Muir has a pawl lock so as long as you set the pawl and the chain / Rode is set in the wheel I would not expect the windlass itself to be an issue, but as mentioned the torque from the pulpit can over time stress the attach points. If that a concern maybe replace the bolts and add a back plate. Unless some other issues with the boat that should be good for decades

          while it does add a few minutes to set it, I stow my bridle at the fore deck, have marked the bridle lines for where to cleat off, and have it down to a process, only adds about 5 minutes during deployment maybe a little longer to clean it and stow for next use. I consider the time spent keeping the stress off the tackle a good trade compared to the cost and effort of replacing them due to stress damage and fatigue and the noise level drop inside the boat is very apparent with an all chain rode.
          4788 PH 2001, Cummins 370's

          MMSI: 338013392
          Call sign: Sea Daze

          Exploring the Salish Sea

          Comment


            #6
            Never have. Never really worried about it but my prime anchoring season is pretty darn calm. There is a clutch on the windlass that if it really started to pull will slip. Based on some very stuck anchors and slipping the clutch occasionally while unsticking there is a fuse in the system and if I wasn't awake from the fact that it would be howling when it slips it would be a great alarm to wake me up.

            I always make sure that we are well hooked before sleeping or heading to shore.

            A bridal does not change your scope. There are no rigid points closer to the water to change the physics. Forces just go up the bridal to the foredeck cleats instead of windlass which are basically the same height above the water.

            The noise of chain waking me up on an otherwise calm morning might be motivation in the future but so far.... not so much

            I won't say I have never had an anchoring fail but I will say my track record is a lot better than a lot of the boats I see out there given where they were when I went to bed and where they were when I woke up bridals or not.
            1999 Sandpiper Pilothouse - Current
            1989 3888 - 2011-2019, 1985 Contessa - 2005-2011, 1986 21' Trophy 1998-2005
            Nobody gets out alive.

            Comment


              #7
              We have an all chain rode of 5/16” G4. Our bridle is a pair of 3/4” 3 strand about 30’ long and attaches to the chain with a modified sea dog chain hook. I view the bridle as the primary way to reduce shock loading on the anchoring system thru it’s elasticity. We deploy it every night or anytime the chain rode would have much tension. I also started using 3’ of swim noodle to cradle the chain between the windlass and the bow pulpit. It quiets the chain a bit while swinging. The noise we get is the 3 strand “clunking” over the gunwale as we swing. We go thru about 90° as we swing.

              Since you have a 5/8” line as part of your rode, I would think that it would be unnecessary to use a snubber when it is part of what you have deployed. That said, only you can determine if other parts of your system can handle the stress. I would hope to use the bridle when I only had chain deployed.
              2000 4788 w Cummins 370's, underhulls, swim step hull extension
              12' Rendova center console with 40HP Yamaha
              MV Kia Orana
              Currently Enjoying the PNW

              Comment


                #8
                Originally posted by kwb View Post
                Never have. Never really worried about it but my prime anchoring season is pretty darn calm. There is a clutch on the windlass that if it really started to pull will slip. Based on some very stuck anchors and slipping the clutch occasionally while unsticking there is a fuse in the system and if I wasn't awake from the fact that it would be howling when it slips it would be a great alarm to wake me up.

                I always make sure that we are well hooked before sleeping or heading to shore.

                A bridal does not change your scope. There are no rigid points closer to the water to change the physics. Forces just go up the bridal to the foredeck cleats instead of windlass which are basically the same height above the water.

                The noise of chain waking me up on an otherwise calm morning might be motivation in the future but so far.... not so much

                I won't say I have never had an anchoring fail but I will say my track record is a lot better than a lot of the boats I see out there given where they were when I went to bed and where they were when I woke up bridals or not.
                I know most of us understand that safe anchoring is a lot more complex than simply dropping a hook and some arbitrary amount of rode.

                Most of your post may be a matter of personal preference and I can respect your choices, however, as a licensed captain I feel obligated to counter some of your statements.

                the mechanics of the bridle, does change the angle of the anchor and that is the actual definition / purpose of scope, the rode does not follow a straight line it is typically a catenary, a properly set bridle is actually lowered into the water and can make a very substantial difference in scope and anchor set, another technique is to add a kellet (weight) on a ring that slides down the rode to change the scope and that can also change the geometry of the rode and anchor by forcing a lower angle to the seabed.

                As this can significantly improve safety of a boat it is something that I would recommend skippers to do a little research on. Most skippers tend to use far to short of rode, I often find myself at 4 to 1, or even 3 to 1 for a lunch hook due to crowded anchorages to minimize swing radius, as I use all chain this is somewhat acceptable, but still has significant risk and I would never rely on that scope when in a blow. The recommended scope is typically 7 to 1, and in any serious wind use all you have to get a low angle to the seabed.

                If the anchor does not lay down on the seabed it will not stay set. The bridle also acts as a damper and minimizes jerking the anchor loose in any choppy anchorage this damping also minimizes jerking on you windlass and deck so it is far easier on your boat.

                I would never rely on use of the windlass clutch as a means for an anchor alarm, or as substitute for the damping effect of a bridle. If your clutch is loose enough to slip under the conditions you are in and noise of anchoring rode transmitting into the hull does not wake you, you may find yourself grounded or possibly worse colliding with another boat while you sleep.
                4788 PH 2001, Cummins 370's

                MMSI: 338013392
                Call sign: Sea Daze

                Exploring the Salish Sea

                Comment


                • kwb
                  kwb commented
                  Editing a comment
                  Respect the opinion but the catenary only changes a little bit unless you are lowering way down into the water (as you said you do) and then you are using the slack chain mostly as a kellet in a sub optimal location unless it is pretty shallow. 99% of people using a bridal aren't doing that. They are hanging a bit below the bow roller out of the water.
                  The use of a proper kellet is a whole other thing and absolutely changes how force is angled at the anchor as tension is applied and keeps the pull closer to horizontal.
                  You also might have noted that my comments pertained to my normal cruising season and were not intended for a heavy blow... sure surprises happen but not very often and while one data point doesn't make a trend a lifetime of boating and a preference for being on anchor v. at the dock has given me a pretty good trend line to know my boundaries.
                  Based on how much my bow will dip to finally extract from the muck on a vertical pull I would guess that there is 800-1000# of tension at a minimum to get clutch to slip. I am not doing the math but I am quite confident that it takes enough wind do generate that kind of tension that I am going to be awake.

                #9
                Originally posted by Knot_Happy View Post
                When I removed the pulpit it made the well known Muir chain hop issue worse and I eventually went to a Lewmar vertical windlass and added a separate chain lock. The chain lock is through bolted to the foredeck with a stainless back plate this completely unloads the windlass when set and transfers the load direct into the boat.
                Can you expand on this more? Perhaps in a separate post. We have to let our anchor and rode out very slowly to avoid chain hop. When the chain hops you can see the pulpit flex up and down. I get really nervous about it anchoring in deep water. Maybe there are improvements that can be made to the Muir Cougar setup without resorting to a new windlass installation? Thank you.
                MV Dreams - 1999 3988
                330 Cummins
                Wrangell, AK

                Comment


                • Knot_Happy
                  Knot_Happy commented
                  Editing a comment
                  First I want to state that the Muir Cougar is an excellent and very rugged windlass, when setup proper and maintained it is one of the best out there.
                  The windlass does have two issues

                  The problem I was referring to regarding chain hop and potential risk are due to the orientation of chain wheel on the horizontal windlass.

                  The horizontal chain wheel specifies minimum of (if I recall correctly)110 degree of engagement minimum. On a boat with a pulpit the anchor stows under the pulpit and the windlass is on top o pulpit and the chain wraps over then drops vertically into the locker. This results in a sufficient angle of engagement of chain.

                  When you remove the pulpit and remount the anchor on top of a roller and the windlass direct on the deck this can significantly reduce the vertical distance between the anchor and wheel top and the chain wheel angle of engagement is not enough. With a reduced angle any bounce in the chain will result in it hopping out of the wheel cogs and it will run free overboard until it hits the seabed. Anything near the chain including body parts can be snagged and damaged.

                  By inherent design a vertical shaft windlass has 180 degree or near that engagement and any bob or bounce is perpendicular the wheel-sides so it simply does not hop out.

                  The other issue can be due to wear of a chain, or the wheel itself, over time the friction of the chain in the wheel can elongate the cog pocket spacing and while it’s not always apparent erosion and abrasion on the chain can make the link spacing erratic, this slight mismatch may cause the chain to rise and fall as it’s retrieved resulting in oscillations and bounce. This can also result in the chain hoping out of the wheel and a runaway anchor. Sometimes a new chain / new chain wheel can resolve this.

                  One solution some people have done to improve safety is to add a top roller over the chain just forward of the windlass. This assures the chain stays at the proper angle of engagement. Before I changed to a vertical windlass I added the top roller and it was very effective, I actually left it in place with the vertical shaft windlass as it keeps the chain from raising up when the anchor arm passes over the bow roller.

                • Renilyab
                  Renilyab commented
                  Editing a comment
                  Knot_Happy;
                  Thank you for the detailed response. If you have a pic of the top roller you fabricated that would be great.

                #10
                Thanks everyone for the infomitive responses. I'll stick with what I've been doing; bridle overnight and just chain on the windlass for a short break.
                1991 4588
                SE Michigan

                Comment


                  #11
                  The OPs original question was regarding when to use a snubber bridle and when not to use it.

                  Bridal are optional equipment so it’s a choice, however the hard data shows when properly deployed it reduces noise, reduces strain on the boat, improves holding (reduces break out) it can be used in an asymmetric rigging to point the boat slightly off line from the anchor to reduce swing and roll from wind and current. If you don’t have any of the above concerns it may not be worth the effort for you.

                  Anchoring is a mix of science, experience and maybe a bit of an art form. As I recommended above some research of respected and trusted sources can be helpful. Bridle/snubber use is one of those practices that for most of us we will never be in conditions where poor practice results in life threatening outcome, however my experience is proper use can increase enjoyment of cruising and reduce wear on equipment.

                  I clipped the below from the Mantus marine website. It adds insight to how much the bridal can help reduce strain on a boat (one of the benefits, but not the only benefit). I am perhaps to a fault a bit driven by an engineering perspective and prefer hard research to anecdotal stories.

                  https://www.mantusmarine.com/mantus-...ubbersbridles/

                  *************
                  For example:

                  So for a 40 foot boat in a 60 knot sustained wind storm, worst expected loads as predicted by ABYC would be 4800 lbs, most experts would agree that this is an inflated number that accounts for the dynamic loads that could be induced by waves and wind gust on top of the static wind loads and assumes the worst drag coefficients.

                  ABYC loads already account for the dynamic loads induced by the use of a non-elastic chain a condition mitigated with the use of a snubber.

                  A properly sized snubber can reduce these loads by 2/3. In our example from 4800 lbs to around 1600 lbs for a 40 foot boat in 60 knots.

                  Practical Sailor article on snubbers, by Drew Fry March 2016, studied this issue and tabulated the loads for a 40 foot monohull boat in 60 knots in the following scenarios:

                  Chain no Snubber – 4,140 lbs (exceeds working load limmit for 5/16 Grade 30 chain)
                  ABYC worst case – 4,898 lbs
                  Chain with a 30 foot ½ inch three strand nylon bridle – 1,574 lbs (the only scenario where load on the chain is below working load limmit for 5/16 chain 1,900 lbs)
                  Chain with a 6 foot 1/2 inch three strand nylon snubber – 3,249 lbs
                  Working Load Limmit for 5/16 Grade 30 Chain 1900 lbs, Breaking Strength 7600 lbs.
                  -62% reduction in peak loads or about 1/3 of the ABYC worst case with the use if 30 foot bridle

                  -Only 22% reduction in peak loads with the use of the 6 foot snubber.

                  Thus the use of the a properly sized snubber can significantly reduce the loads on your anchor and you chain, by as much as 2/3 with a 30 foot bridle.

                  **************


                  in the end, for this topic, experience and personal preference is likely the answer to the original question.
                  4788 PH 2001, Cummins 370's

                  MMSI: 338013392
                  Call sign: Sea Daze

                  Exploring the Salish Sea

                  Comment


                    #12
                    These Photos are added regarding the top roller question and comments and request for photo, they are not directly related to the bridle discussion, but may be of interest to others.


                    I do not have a photo showing the top roller with the Muir Horizontal shaft, however the roller is located as it was before changing to the vertical shaft.
                    this is a custom anchor roller and windlass installation with a pulpit removal on our 4788.


                    Description, second photo, right to left

                    windlass on a 2 inch spacer through bolted to a 1/4 inch thick stainless back plate plate and two aluminum channels running port to starboard inside the anchor chain locker

                    Stainless turn buckle with devils claw for anchor / chain safety catch. Hooks into the chain just before the top roller, through bolted to same back plate as the windlass.

                    Chain lock, on a 1 inch spacer through bolted into a channel and back plate inside the chain locker,

                    Top roller placed to capture the anchor arm as it completes retrieval and rests in its stowed position, with a horizontal shaft chain wheel the top roller assured the contact around the windlass chain wheel remained constant and sufficient even under a choppy sea.

                    the pedestal is for a spot light that at the time of these photo was not yet installed.

                    the roller was purchased from Fisheries supply in Seattle, I straightened the side brackets and bolted it into the anchor roller channel as shown.



                    Click image for larger version

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                    Attached Files
                    4788 PH 2001, Cummins 370's

                    MMSI: 338013392
                    Call sign: Sea Daze

                    Exploring the Salish Sea

                    Comment


                    • Renilyab
                      Renilyab commented
                      Editing a comment
                      Thank you for taking the time to post the pictures and describe the setup. It looks very robust.

                    #13
                    We use a Mantis Bridle on all our overnights and it reduces our scope and allows for a tighter swing radius as mentioned before. a quick question. has anyone put a wireless remote on the windless? As i haven't been able to fit into the Locker due to Diet requirements..lol.. Also the PO installed 300 ft 5/16 chain however the bitter end is a loop that uses its size to stop it from exit out of the chain locker. I would like to change this to line and attach it to the boat. What size and how long should i make it?
                    Charles Matthews
                    Camelot 1998 4788
                    Old Saybrook, CT

                    Comment


                    • Knot_Happy
                      Knot_Happy commented
                      Editing a comment
                      I have a wireless remote for my windlass as part of my thruster remote. The receiver is located under my fly bridge console to give it the best reception, the actual switching is just a relay in the rode locker that activates the same circuit as the foot switches. Does not require much space.

                      While it is functional I seldom use it as sight is limited over the bow to watch where the rode is from either helm (I would hate to drive over the chain if it looped back). typically the admiral operates the anchor retrieval while I maneuver the boat. I have used it while out single handed and verify it is operational before any long cruising.

                    #14
                    Our bitter end is about a 20’ length of 5/8” 3 strand tied to an eyelet it the anchor locker. It’s big enough to stop the chain from a complete runaway but small enough to be cut in an emergency.
                    2000 4788 w Cummins 370's, underhulls, swim step hull extension
                    12' Rendova center console with 40HP Yamaha
                    MV Kia Orana
                    Currently Enjoying the PNW

                    Comment


                    • Knot_Happy
                      Knot_Happy commented
                      Editing a comment
                      I’ve had to cut my anchor loose when it got stuck under a sunk sailboat, based on my experience and not any specific criteria, A good minimum length is to reach past your last roller and suspend the last chain link off the deck, but still (if not a rough sea emergency) allow you to reach the last link. This can allow you to attach a buoy, or fender to the chain end prior to cutting the line if it’s possible worth retrieving. if it’s an emergency and under significant tension this will prevent the chain from possibly snagging on its way overboard. In the situation I had I came back with dive gear and retrieved my anchor several weeks later, in most situations you likely will be loosing the anchor for good, but in my case it was of sufficient value and in a safe harbor so I went back for it..

                      I currently have a bout 15t of 1/2 inch nylon 3 strand, have 300ft of 5/16 HT chain so the line is not intended as anchor rode. it is there to be cut in an emergency situation.

                    • Woodsea
                      Woodsea commented
                      Editing a comment
                      Knot Happy brings up a really good point about possibly attaching a line for marking for possible anchor retrieval. I’ve got 100’ of 1/4” floating line that would be simple to attach to the bitter end of the chain and just flake it in the bottom of the anchor hold. In theory, it will at least be floating to the surface if anchor is cut loose in less than 100’. I think I will do that next time it’s convenient to unload all the chain.

                      Also above I said the rope bitter end is tied. I misspoke. It is spliced onto the chain so it will fit thru the hawse hole.

                    #15
                    After 55 years on the water my advice is if you are going to leave the boat, set the hook.

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