Wondering what people use for an anchor bridle for the 310 with all chain anchoring? I have a one-piece Y shaped braided bridle that is 5 ft long with a mantus chain hook that I have used for a few years with good success. It is 5 ft long because that is the length that Jesse recommended based upon his experience. Have been anchored in 40 knot winds with no problems. Just wondering if the bridle shouldn't be longer than 5 ft to provide more stretch and in case we get caught in winds >40 knots? Have seen commercially available bridles from 14-24 ft in length and even longer than that. Having a bridle almost as long as the boat does not seem to make sense to me and sounds unwieldy to handle when setting and retrieving. Maybe this is just a solution looking for a problem?
Anchor Bridle
- Thread starter Cat 310 #1 in GA
- Start date
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,386
I bought the Mantus Bridal
Mine is the middle size. For your boat I suspect the Small will be fine.
Their lines are 3 strand nylon. Plenty of stretch my boat handled an overnight with the storm blowing 30-50 knots. I was on a hundred ft of chain plus the 26 ft of bridal a year ago. Nylon 3 strand has 20% stretch.
| Bridle Size | Small | Medium | Large |
|---|---|---|---|
| Boat Size | 30 – 40 feet | 40 – 50 feet | 50 – 70 feet |
| Rope: Three Strand Nylon Diameter | 5/8″ SWL 1525 lbs UBS 12,200 lbs | 3/4″ SWL 2087 lbs UBS 16,700 lbs | 1″ SWL 3675 lbs UBS 29,400 lbs |
| Bridle length overall | 23 feet | 26 feet | 30 feet |
| Individual Leg length | 20 feet | 22 feet | 26 feet |
Mine is the middle size. For your boat I suspect the Small will be fine.
Their lines are 3 strand nylon. Plenty of stretch my boat handled an overnight with the storm blowing 30-50 knots. I was on a hundred ft of chain plus the 26 ft of bridal a year ago. Nylon 3 strand has 20% stretch.
Note that JS's chart does not mention all chain anchoring. That is one of the advantages to chain. It has its own kind of stretch as it lifts with the waves and wind off the bottom, softening the pull. If you are concerned for a big blow, you could think about adding a kellet and/or paying out more scope. 4:1 chain should be good for most conditions, but 5:1 scope should allow you to sleep like a land lubber.
-Will
-Will
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,386
Will is absolutely correct. The all chain rode you get a catenary effect. The challenge comes as the winds build and the chain lifts off the sea floor. Then with each gust you get the chain stretched to the end and a tug against the boat. You need something to protect the boat so the chain doesn't yank a cleat off the bow or worse the windlass where the chain is wrapped. That something is a snubber or a bridal. The snubber is connected to the chain and then tied to a secure fitting on the boat. (Cleat of Samson Post)
Catenary Effect
Because of its weight a chain rode will sag in light to medium winds requiring significant energy to straighten it out. This catenary effect provides excellent energy absorption.
Catenary Effect
Because of its weight a chain rode will sag in light to medium winds requiring significant energy to straighten it out. This catenary effect provides excellent energy absorption.
The energy required to straighten the sag in the chain is called catenary and this in turn provides excellent energy absorption in light winds (up to about 20 knots). The sag in the chain also gives the rode a good angle of pull on the anchor.
Other than one catamaran rental in the BVIs, I'm new to this subject. I've always had rode that was a mix of 25-50 feet of chain, and then nylon, such that I was always on the nylon rode by the time sufficient scope was out. I have yet to anchor out with my newest boat that has 100' of chain, so I've been doing some reading on the subject and its apparently its own can of worms. FYI, since I'm not cruising anywhere exotic I chose the Mantus system, which will be fine for everything except for the rare really bad conditions (a thunderstorm on the Chesapeake Bay notwithstanding). But here's some of the more informative pieces I've read on this.
www.practical-sailor.com
Updated version of the table in the report:
www.practical-sailor.com
For cruisers who may run into challenging conditions:
www.practical-sailor.com
Other informative articles:
www.practical-sailor.com
What is Ideal Snubber Size? - Practical Sailor
Since 1974, Practical Sailor’s independent testing has taken the guesswork out of boat and gear buying.
www.practical-sailor.com
Snubber Diameter for Larger Sailboats - Practical Sailor
Since 1974, Practical Sailor’s independent testing has taken the guesswork out of boat and gear buying.
www.practical-sailor.com
For cruisers who may run into challenging conditions:
Adjustable Snubber Bridle and Chain Hook - Practical Sailor
This unique anchor bridle system is designed especially for multihulls, but is applicable to monohulls as well. Unlike any anchor snubber system we have reviewed before, this setup is fully adjustable from the boat cockpit. The doubled-snubber arrangement also helps keep the chain hook off the...
www.practical-sailor.com
Other informative articles:
Is an Anchor Snubber Line really Necessary?
If you have an all-chain rode then yes, you definitely need an anchor snubber line. But what's best, a single snubber line or a bridle? Well, it depends...
www.sailboat-cruising.com
A Different Approach to the Catamaran Bridle - Practical Sailor
Since 1974, Practical Sailor’s independent testing has taken the guesswork out of boat and gear buying.
www.practical-sailor.com
Similar to the above with all 5/16" chain, I use the small Mantus on our 33' boat; but, decided that the Mantus chain hook was just to darn ungainly making it potentially dangerous for our use. I replaced it with the Mantus Snubber Pendant and connect it to the bridle thimble with a 3/8" dyneema soft shackle. If ever needed I will cut the soft shackle and retrieve the bridle much quicker than trying to take the chain hook off.
Interesting idea. Super helpful video on this here:
Mantus Snubber Pendant - Pendant Line | Mantus Marine
The Mantus snubber pendant attaches the snubber line to chain or line rode. Ours are made of the strongest UHMWPE material for extra durability. Buy yours now!
www.mantusmarine.com
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,386
In a hurry, you may need something very sharp and able too withstand the blunting effect of dyneema on steel.
Might I suggest.
A ceramic blade riggers knife
I have found them great on ultra-high molecular weight polyethylene (UHMwPE) fiber.... Dyneema
Thanks all, I just ordered a bridle from 48 North that was on sale and more reasonably priced that the mantus version. I have a second mantus chain hook that I will attach to this. Will still use my 5 ft long bridle since it is so easy to use but this 18 ft long bridle will be handy if the winds pick up beyond 20 or 25 knots.
bob
bob
I really like that 48 North lets you pick from a wide range of lengths for your bridle. The prices are excellent too. Thanks for posting. I wasn't aware of them.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,386
The Devil is in the Details.
Cost of a 26' Bridle, 5/8ths 3 strand line designed for a 30-40ft boat.
Mantus through Fisheries $204 appears to be free shipping
48ºNorth Marine. $200 shipping $29...
I love to see a NW company engaged in the marine marketing business. They have been engaged since 2018 and appear to have a focused business plan providing a USA made product at a fair price. You may be able to get more variety of items, i.e. shorter lengths or smaller diameter lines. Delivered costs appear to be pretty close when doing an Apple to Apple comparison. It appears to be a skipper's choice (as always).
I would encourage you to get at a minimum 5/8 3 strand. It has a Rope Breaking Strength 12,200 lb. Check the hardware that comes with the bridle to assure it has adequate strength. I note that the 48º North product comes with a 1/2" SS shackle. Is the pin captured? If not get a couple replacements. You will be dropping the pin overboard one night when you are attaching the bridle. It will not be the time to chastise your failure to have a spare.
You may also consider a soft shackle made of dyneema, as a back up when the shackle chooses to go swimming.
Cost of a 26' Bridle, 5/8ths 3 strand line designed for a 30-40ft boat.
Mantus through Fisheries $204 appears to be free shipping
48ºNorth Marine. $200 shipping $29...
I love to see a NW company engaged in the marine marketing business. They have been engaged since 2018 and appear to have a focused business plan providing a USA made product at a fair price. You may be able to get more variety of items, i.e. shorter lengths or smaller diameter lines. Delivered costs appear to be pretty close when doing an Apple to Apple comparison. It appears to be a skipper's choice (as always).
I would encourage you to get at a minimum 5/8 3 strand. It has a Rope Breaking Strength 12,200 lb. Check the hardware that comes with the bridle to assure it has adequate strength. I note that the 48º North product comes with a 1/2" SS shackle. Is the pin captured? If not get a couple replacements. You will be dropping the pin overboard one night when you are attaching the bridle. It will not be the time to chastise your failure to have a spare.
You may also consider a soft shackle made of dyneema, as a back up when the shackle chooses to go swimming.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,386
If saving money is the goal, I would encourage you to learn the seaman's art of ropes. Learn to buy rope in bulk at warehouse pricing. Sometimes buying cut ends in the over cut bin are half price or less. Same rope just in a length the seller can not retail.
Then make your own splice. Whipped ends, or eye loop to the desired length.
These skills last a lifetime. You'll be able to help many a new boater and pass along this skill as it has traditionally been done sailor to sailor drinking Rum or Beer.
Then make your own splice. Whipped ends, or eye loop to the desired length.
These skills last a lifetime. You'll be able to help many a new boater and pass along this skill as it has traditionally been done sailor to sailor drinking Rum or Beer.
I've never understood the desire for a bridle if they aren't tying up to a mooring or have a bowsprit.
With my spring off to one side of the bow in a chock, the boat swings a bit off center and therefore has less tendency to sail.
You can Also set up a lee for boarding the boat from the dinghy, or the reverse. We used a 25 to 35' snub, with a thimble and eye splice, and a suitable galvanized chain hook. Nothing fancy, but with unlimited strength in terms of the weight of my boat in anything less than hurricane strength winds and a good 6' sea. After that, there are no set rules. Mine is as many anchors as I have, deployed.
With my spring off to one side of the bow in a chock, the boat swings a bit off center and therefore has less tendency to sail.
You can Also set up a lee for boarding the boat from the dinghy, or the reverse. We used a 25 to 35' snub, with a thimble and eye splice, and a suitable galvanized chain hook. Nothing fancy, but with unlimited strength in terms of the weight of my boat in anything less than hurricane strength winds and a good 6' sea. After that, there are no set rules. Mine is as many anchors as I have, deployed.
Yes me too. I got the 5/8" bridle at 18 ft long for $135 + 28 for shipping. Should be perfect for use with my mantus chain hook.
And the Diameter?
The simple answer to that question is 'as small a diameter as you think you can get away with' as, pound for pound, a thin line will stretch more than a thicker one - but of course you don't want it to break.
As a rule of thumb...
For a boat 12m long overall with bow height of 1m above the waterline, the recommended anchor chain length to be deployed is...
For a 12m boat carrying a 20kg anchor, 70m of 10mm chain is probably as much weight as you'd want in your anchor locker, but this would still give you a 4:1 scope in 15m (50ft) depth of water.
Snubber line for 31Ft boat = 40 Ft X 3/8” (1/2”)
I followed this info and everything worked out really well ...... I'm on the Great Lakes System.
The simple answer to that question is 'as small a diameter as you think you can get away with' as, pound for pound, a thin line will stretch more than a thicker one - but of course you don't want it to break.
As a rule of thumb...
- Boat length <12m: 16mm line;
- Boat length 12-16m: 20mm line;
- Boat length 16-20m: 25mm line;
- The Effective Depth
- Your electronic depth sounder displays the depth between the transducer and seabed, unless you've entered offsets such that it shows either the depth below the keel, or the full depth from the surface.
- Is your depth sounder display giving you depth below transducer, keel or actual depth?
- To this latter depth you'll need to add the height of the bow roller above the surface to get the effective depth. Why? Well, it's from the bow roller that you'll measure the length of anchor chain to be deployed.
For a boat 12m long overall with bow height of 1m above the waterline, the recommended anchor chain length to be deployed is...
Water Depth | Effective Depth | 4:1 Scope (minimum) | Plus LOA x 2 | Chain Deployed (ideal) |
3m | 4m | 16m | 24m | 40m |
5m | 6m | 24m | 24m | 48m |
10m | 11m | 44m | 24m | 68m |
Snubber line for 31Ft boat = 40 Ft X 3/8” (1/2”)
I followed this info and everything worked out really well ...... I'm on the Great Lakes System.
