Awhile back, we had a question concerning proper length of anchor rodes, but I'm wondering about the diameters. I have a 35' boat and I can go to numerous sources and find conflicting info on rope and chain sizes. For instance, one source says to use 1/8" of rope for every 9' of boat length and one-half of that for chain. This formula would give 1/2" rope and 1/4" chain for a 35' boat. I have found other sources that give almost every possible size as the "proper" size. I happen to have a brand new length of 1/2" rope and a 30' length of 1/4" stainless chain and I guess I'm hoping(wishing) that those sizes are adequate, but deep-down I probably feel they're too small, otherwise I wouldn't be posting this question. I use a danforth anchor and anchor in sand/mud found on Florida's west coast. Has anyone had these sizes (1/2" & 1/4") fail them?
Anchor rode...what size?
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Opinion...only
My experience would lead me to believe that a danforth style anchor would break out of sand and mud long before the rode you describe would be tested. That said, I bought 5/8-5/16 for my Catalina 320 Delta (22#) primary anchor and have 1/2-1/4 on my Danforth lunch hook back-up. I sleep better that way.
My experience would lead me to believe that a danforth style anchor would break out of sand and mud long before the rode you describe would be tested. That said, I bought 5/8-5/16 for my Catalina 320 Delta (22#) primary anchor and have 1/2-1/4 on my Danforth lunch hook back-up. I sleep better that way.
Beneteau 361
Roland, I have a B361 and have 200' of 5/8" and 30' of 5/16 chain on a 35#CQR. I would think the 1/2"- 1/4" might be a little to light good luck
Roland, I have a B361 and have 200' of 5/8" and 30' of 5/16 chain on a 35#CQR. I would think the 1/2"- 1/4" might be a little to light good luck
Your probably ok. Looking at the rated load
of 1/2" 3 strand NE ropes rating is 7500lbs . Like it was mentioned before, the anchor would most likely drag before the line would fail. I think the bigger concern is probably chafing. In general bigger lines can handle chafing (and eventual failure) longer than a smaller line, so I would think the concern would be mitigated somewhat by having good chafing gear set-up when you are in a blow. That said, I have a 16,000 lb (at least, LOL) 36 foot boat & I'm with these other guys @ 5/8" rode and 5/16" chain (I only have 15 foot of chain that someday plan on making longer, but everything is working fine now)
of 1/2" 3 strand NE ropes rating is 7500lbs . Like it was mentioned before, the anchor would most likely drag before the line would fail. I think the bigger concern is probably chafing. In general bigger lines can handle chafing (and eventual failure) longer than a smaller line, so I would think the concern would be mitigated somewhat by having good chafing gear set-up when you are in a blow. That said, I have a 16,000 lb (at least, LOL) 36 foot boat & I'm with these other guys @ 5/8" rode and 5/16" chain (I only have 15 foot of chain that someday plan on making longer, but everything is working fine now)
Ground Tackle Recomendations
Hi, the standard for ground tackle sizes comes from ABYC (American Boat and Yacht Council). They have a chart that is broken down by boat type (Sail or Power), length, and type of usage (Storm, mooring, etc.). The result is shown in safe working load. Then compair that number to the specification of the rope and chain manufacturer. Hope this helps.
Hi, the standard for ground tackle sizes comes from ABYC (American Boat and Yacht Council). They have a chart that is broken down by boat type (Sail or Power), length, and type of usage (Storm, mooring, etc.). The result is shown in safe working load. Then compair that number to the specification of the rope and chain manufacturer. Hope this helps.
All chain is not created equal
The size of the links and the strength are not the same. Stainless steel is usually stronger. I recently bought some chain and the high strength was about twice as strong as regular chain of the same size. Windage is the critical factor for the stress on your rode. A dodger and bimini add a lot of windage. Catamarans have more windage than monohulls. High volume wide beam more than low volume narrow boats. Another question would be your sailing style. Do you expect to be out anchored in survival conditions??? If I already had a rode and chain I'd probably use it unless there were very good reasons. In twenty years of sailing only once have I been in winds high enough to worry about the rode breaking. That said I always put down two anchors. Mostly because I've had an anchor not reset a couple of times. Once because of a wedged rock that prevented the flukes from moving. The other was that the anchor slid across the grass bottom. Fortunately I was awake at those times and we weren't blown ashore.
The size of the links and the strength are not the same. Stainless steel is usually stronger. I recently bought some chain and the high strength was about twice as strong as regular chain of the same size. Windage is the critical factor for the stress on your rode. A dodger and bimini add a lot of windage. Catamarans have more windage than monohulls. High volume wide beam more than low volume narrow boats. Another question would be your sailing style. Do you expect to be out anchored in survival conditions??? If I already had a rode and chain I'd probably use it unless there were very good reasons. In twenty years of sailing only once have I been in winds high enough to worry about the rode breaking. That said I always put down two anchors. Mostly because I've had an anchor not reset a couple of times. Once because of a wedged rock that prevented the flukes from moving. The other was that the anchor slid across the grass bottom. Fortunately I was awake at those times and we weren't blown ashore.
Working Load Limits
O_Salt: Indicates that ABYC has a chart on Anchor Rode Selection. I’ve never seen such a thing - can you direct me to it? Tom & Fred: Indicate that Stainless chain is usually stronger than equivalent-sized “regular” chain. I’d slightly modify that claim: Per National Asscociation of Chain Manufacturers (NACM): http://www.cmindustrial.com/products/chains/nacm.asp 1/4" Proof Coil (Grade 30): 1,300# WLL & 5,200# MBS 1/4" High Test (Grade 40): 2,600# WLL & 7,800# MBS 1/4" Transport (Grade 70): 3,150# WLL & 12,600# MBS 1/4" Stainless High Test: 1,570# - 1,860# WLL & 6,300# MBS Also, Stainless is generally considered to be much more “brittle” than mild-steel chain, and may also be subject to corrosion (chloride impingement, stress & crevice) at the welds. That said, I include both S/S H.T. as well as Grade 70 Transport Chains in my complement. For a 35 Ft. Mono-hull sailboat, many authorities would generally recommend something on the order of : ½" - 9/16" Three-Strand Nylon (As small as 3/8" for Lunch Hook) 1/4" - 3/8" Proof Coil Chain (As small as 3/16"-1/4" for Lunch Hook) The ABS has a formula for calculating anchor & rode sizes: Goto: 5/2.15.2 & 5/2.15.3 @ # http://www.eagle.org/rules/supplement/61-HSC-SupNov01.pdf Regards, Gord
O_Salt: Indicates that ABYC has a chart on Anchor Rode Selection. I’ve never seen such a thing - can you direct me to it? Tom & Fred: Indicate that Stainless chain is usually stronger than equivalent-sized “regular” chain. I’d slightly modify that claim: Per National Asscociation of Chain Manufacturers (NACM): http://www.cmindustrial.com/products/chains/nacm.asp 1/4" Proof Coil (Grade 30): 1,300# WLL & 5,200# MBS 1/4" High Test (Grade 40): 2,600# WLL & 7,800# MBS 1/4" Transport (Grade 70): 3,150# WLL & 12,600# MBS 1/4" Stainless High Test: 1,570# - 1,860# WLL & 6,300# MBS Also, Stainless is generally considered to be much more “brittle” than mild-steel chain, and may also be subject to corrosion (chloride impingement, stress & crevice) at the welds. That said, I include both S/S H.T. as well as Grade 70 Transport Chains in my complement. For a 35 Ft. Mono-hull sailboat, many authorities would generally recommend something on the order of : ½" - 9/16" Three-Strand Nylon (As small as 3/8" for Lunch Hook) 1/4" - 3/8" Proof Coil Chain (As small as 3/16"-1/4" for Lunch Hook) The ABS has a formula for calculating anchor & rode sizes: Goto: 5/2.15.2 & 5/2.15.3 @ # http://www.eagle.org/rules/supplement/61-HSC-SupNov01.pdf Regards, Gord
Anchor Rode
1/4" chain for a 35 foot anything is not big enough. Are we not forgeting that aside from strenth and chafe, chain, because of it's weight, also provides the caternary nessesary so that the anchor will not break out so easy.Caternary also absorbs shock loads. 1/4" chain won't give you much of it unless there's no wind. It'just not heavy enough. As for the line part of a rode,let's also not forget that not any type of line will do either.Would you use sta-set X as a rode? No! Because it does not stretch.Shock loads will rip your anchor out of the bottom real quick if the rode doesn't stretch, so,you would use properly sized three strand nylon line. For general anchoring with my Endeavour 32 @ 12000 Lbs. displacement, I use 5/8" three strand nylon,twenty feet of 3/8 G3(proof coil)chain and a Bruce 33Lb. Dennis
1/4" chain for a 35 foot anything is not big enough. Are we not forgeting that aside from strenth and chafe, chain, because of it's weight, also provides the caternary nessesary so that the anchor will not break out so easy.Caternary also absorbs shock loads. 1/4" chain won't give you much of it unless there's no wind. It'just not heavy enough. As for the line part of a rode,let's also not forget that not any type of line will do either.Would you use sta-set X as a rode? No! Because it does not stretch.Shock loads will rip your anchor out of the bottom real quick if the rode doesn't stretch, so,you would use properly sized three strand nylon line. For general anchoring with my Endeavour 32 @ 12000 Lbs. displacement, I use 5/8" three strand nylon,twenty feet of 3/8 G3(proof coil)chain and a Bruce 33Lb. Dennis
ABYC
Hi, here is the link to purchase the section H-40. http://64.78.59.48/merchant.mvc?Screen=PROD&Product_Code=H-40&Category_Code=DL_STANDARDS If you send me the spec on your boat, I will look it up for you.
Hi, here is the link to purchase the section H-40. http://64.78.59.48/merchant.mvc?Screen=PROD&Product_Code=H-40&Category_Code=DL_STANDARDS If you send me the spec on your boat, I will look it up for you.
H-40
Thanx O_Salt, how could I have missed it?
From ABYC 'H-40' table 1 - Design Loads for deck hardware: 35 Ft Sailboat Boat c/w 10' Beam Permanent Mooring = 2,700# Storm Anchor = 1,800# Working Anchor = 900# and from Table 2 - WLL for Anchor Rodes: 1/2" Three-Strand Nylon = 709# WLL 5/8" = 1,114# 3/4" = 1,598# 1/2" Double-Braid Nylon = 816# 5/8" = 1,275# 3/4" = 1,813# and 1/4" Proof-Coil Galvanized Chain = 1,300# 5/16" P-C = 1,900# 3/8" P-C = 2,650# 1/4" High-Test Chain = 2,600# 5/16" H-T = 3,900# 3/8" H-T = 5,400 So, for your Storm Anchor, ABYC would seem to be recommending the following minimums: 3/4" Double Braid Nylon c/w 5/16" Proof-Coil (or 1/4" Hight-Test) Chain or 7/8" Three-Strand Nylon and for your Working Anchor: 5/8" Nylon (either) c/w 1/4" Chain (either) So - Roland: Your intuition (that your 1/2" c/w 1/4" is TOO SMALL) seems to be bourn out. I agree, you've got a lunch hook, or 3RD anchor rode.
Thanx O_Salt, how could I have missed it?
From ABYC 'H-40' table 1 - Design Loads for deck hardware: 35 Ft Sailboat Boat c/w 10' Beam Permanent Mooring = 2,700# Storm Anchor = 1,800# Working Anchor = 900# and from Table 2 - WLL for Anchor Rodes: 1/2" Three-Strand Nylon = 709# WLL 5/8" = 1,114# 3/4" = 1,598# 1/2" Double-Braid Nylon = 816# 5/8" = 1,275# 3/4" = 1,813# and 1/4" Proof-Coil Galvanized Chain = 1,300# 5/16" P-C = 1,900# 3/8" P-C = 2,650# 1/4" High-Test Chain = 2,600# 5/16" H-T = 3,900# 3/8" H-T = 5,400 So, for your Storm Anchor, ABYC would seem to be recommending the following minimums: 3/4" Double Braid Nylon c/w 5/16" Proof-Coil (or 1/4" Hight-Test) Chain or 7/8" Three-Strand Nylon and for your Working Anchor: 5/8" Nylon (either) c/w 1/4" Chain (either) So - Roland: Your intuition (that your 1/2" c/w 1/4" is TOO SMALL) seems to be bourn out. I agree, you've got a lunch hook, or 3RD anchor rode.H-40
Thanx O_Salt, how could I have missed it? From ABYC 'H-40' table 1 - Design Loads for deck hardware: 35 Ft Sailboat Boat c/w 10' Beam Permanent Mooring = 2,700# Storm Anchor = 1,800# Working Anchor = 900# and from Table 2 - WLL for Anchor Rodes: 1/2" Three-Strand Nylon = 709# WLL 5/8" = 1,114# 3/4" = 1,598# 1/2" Double-Braid Nylon = 816# 5/8" = 1,275# 3/4" = 1,813# and 1/4" Proof-Coil Galvanized Chain = 1,300# 5/16" P-C = 1,900# 3/8" P-C = 2,650# 1/4" High-Test Chain = 2,600# 5/16" H-T = 3,900# 3/8" H-T = 5,400 So, for your Storm Anchor, ABYC would seem to be recommending the following minimums: 3/4" Double Braid Nylon c/w 5/16" Proof-Coil (or 1/4" Hight-Test) Chain or 7/8" Three-Strand Nylon and for your Working Anchor: 5/8" Nylon (either) c/w 1/4" Chain (either)
Thanx O_Salt, how could I have missed it?
From ABYC 'H-40' table 1 - Design Loads for deck hardware: 35 Ft Sailboat Boat c/w 10' Beam Permanent Mooring = 2,700# Storm Anchor = 1,800# Working Anchor = 900# and from Table 2 - WLL for Anchor Rodes: 1/2" Three-Strand Nylon = 709# WLL 5/8" = 1,114# 3/4" = 1,598# 1/2" Double-Braid Nylon = 816# 5/8" = 1,275# 3/4" = 1,813# and 1/4" Proof-Coil Galvanized Chain = 1,300# 5/16" P-C = 1,900# 3/8" P-C = 2,650# 1/4" High-Test Chain = 2,600# 5/16" H-T = 3,900# 3/8" H-T = 5,400 So, for your Storm Anchor, ABYC would seem to be recommending the following minimums: 3/4" Double Braid Nylon c/w 5/16" Proof-Coil (or 1/4" Hight-Test) Chain or 7/8" Three-Strand Nylon and for your Working Anchor: 5/8" Nylon (either) c/w 1/4" Chain (either)I knew I could count on you guys....
Thanks for everyone's input. Well, for the plus side, I eat (& drink) a lot of lunch aboard my boat so it seems that I have a great lunch hook. Thanks again for everyone's input.
Thanks for everyone's input. Well, for the plus side, I eat (& drink) a lot of lunch aboard my boat
so it seems that I have a great lunch hook. Thanks again for everyone's input.Gord How much wind to generate that 900#??
Just curious about how they came up with 900#s. And also if you have two anchors down would the requirement be cut in half??? Sometimes I like my anchors out 90 degrees to the wind so that the rodes form a V to prevent the boat from sailing back and forth all night.
Just curious about how they came up with 900#s. And also if you have two anchors down would the requirement be cut in half??? Sometimes I like my anchors out 90 degrees to the wind so that the rodes form a V to prevent the boat from sailing back and forth all night.
900#
ABYC Notes that the values in Table 1 (Design Loads for Sizing Deck Hardware) "include the effects of wind, current, and wave action." They don't attribute their source. The ABS link I referenced earlier gives a formula for determining anchor sizes, which includes several factors, including: Wind Velocity: Not less than 50 knots Current: Not less than 3 knots Displacement of craft Projected Area of Craft See Guide for Building & Classing http://www.eagle.org/rules/supplement/61-HSC-SupNov01.pdf And a very intersting discussion "Tuning an Anchor Rode" at: http://alain.fraysse.free.fr/sail/rode/forces/forces.htm No - 2 Anchors don't split the load equally (halving it on each). Prudence demands that EACH anchor be capable of carrying the entire load on it's own. Regards, Gord
ABYC Notes that the values in Table 1 (Design Loads for Sizing Deck Hardware) "include the effects of wind, current, and wave action." They don't attribute their source. The ABS link I referenced earlier gives a formula for determining anchor sizes, which includes several factors, including: Wind Velocity: Not less than 50 knots Current: Not less than 3 knots Displacement of craft Projected Area of Craft See Guide for Building & Classing http://www.eagle.org/rules/supplement/61-HSC-SupNov01.pdf And a very intersting discussion "Tuning an Anchor Rode" at: http://alain.fraysse.free.fr/sail/rode/forces/forces.htm No - 2 Anchors don't split the load equally (halving it on each). Prudence demands that EACH anchor be capable of carrying the entire load on it's own. Regards, Gord
900Lbs.
If this helps... 52Kts.of wind on a twenty foot sailboat= 1,000 lbs of pull on the rode. Thirty footer=2,000,Lbs Forty=3,500 Fifty=5,000 This is with no seas running. Dennis
If this helps... 52Kts.of wind on a twenty foot sailboat= 1,000 lbs of pull on the rode. Thirty footer=2,000,Lbs Forty=3,500 Fifty=5,000 This is with no seas running. Dennis
I don't believe you!!!!
A boat with it's bow into the wind would present a cross section that is not proportional to it's length. Beam would be the critical factor. Also the mast height which adds a lot of windage is not proportional to boat length. What about dodgers and biminis??? I am not disputing that you read these values from some table and they might be a good rule of thumb. But one of the rules for preparing for a huricane is to remove all sources of windage possible. Especially sails,booms,dodgers and bimini's.
A boat with it's bow into the wind would present a cross section that is not proportional to it's length. Beam would be the critical factor. Also the mast height which adds a lot of windage is not proportional to boat length. What about dodgers and biminis??? I am not disputing that you read these values from some table and they might be a good rule of thumb. But one of the rules for preparing for a huricane is to remove all sources of windage possible. Especially sails,booms,dodgers and bimini's.
Ok...how'bout this one
Ok Tom...just for you... I have another graph that shows that in a fifty-four Kt.blow in the Columbia River, the pull an the rode was three hundred four Lbs. on a twenty=one Ft. sloop or cutter.Which number would you go with? Now...as for the boom or dodger, or proportional to.. or beam or blah,blah friggin' blah, if you won't be satisfied untill you get those kind of numbers,you'll just have to go out in a storm or hurricane With your little tention meter and get them yourself. Hope this helps, Dennis
Ok Tom...just for you... I have another graph that shows that in a fifty-four Kt.blow in the Columbia River, the pull an the rode was three hundred four Lbs. on a twenty=one Ft. sloop or cutter.Which number would you go with? Now...as for the boom or dodger, or proportional to.. or beam or blah,blah friggin' blah, if you won't be satisfied untill you get those kind of numbers,you'll just have to go out in a storm or hurricane With your little tention meter and get them yourself. Hope this helps, Dennis
What the numbers mean
The table #1 in the ABYC section H-40 are the recommended safe working load of the ground tackle that ABYC recommends. They state that if the beam is greater than what is referenced for the length to go to the beam that equals your vessel. This manual is an industry guideline used by boat manufactures for building boats and recommending equipment. These numbers are not the loads you would normally see. They probable have a safety factor build in. In extreme conditions these numbers could probably be exceeded. Use common sense when sizing your ground tackle. If you over size to the extreme you are spending more money and adding additional weight to the front of the boat and increasing the size and cost of the windlass. Windlass's are sized primarily on the total weight of the ground tackle. If you use the storm anchor quidlines layed out in the manual, you should have a very secure anchoring system. This is the sizing most OEM's use when chosing a ground tackle to include on a boat they build.
The table #1 in the ABYC section H-40 are the recommended safe working load of the ground tackle that ABYC recommends. They state that if the beam is greater than what is referenced for the length to go to the beam that equals your vessel. This manual is an industry guideline used by boat manufactures for building boats and recommending equipment. These numbers are not the loads you would normally see. They probable have a safety factor build in. In extreme conditions these numbers could probably be exceeded. Use common sense when sizing your ground tackle. If you over size to the extreme you are spending more money and adding additional weight to the front of the boat and increasing the size and cost of the windlass. Windlass's are sized primarily on the total weight of the ground tackle. If you use the storm anchor quidlines layed out in the manual, you should have a very secure anchoring system. This is the sizing most OEM's use when chosing a ground tackle to include on a boat they build.
Ground Tackle Sizing Tutorial
I highly recommend that everyone (interested in the numbers) read "Tuning an Anchor Rode" at: http://alain.fraysse.free.fr/sail/rode/forces/forces.htm Excerpted from the article: ... Within these hypotheses, for a 40 ft yacht, equation (3.1) yields the following forces (in daN - to convert into lb, multiply by 2.2): 40 ft Yacht Monohull Catamaran Trimaran Powerboat ABYC's ref. Wind 0̊ 30̊ 0̊ 30̊ 0̊ 30̊ 0̊ 30̊ 10 kt 18 37 27 59 22 46 21 49 56 20 kt 74 150 107 236 89 185 83 196 226 30 kt 166 337 240 530 200 416 187 442 508 40 kt 294 600 427 943 356 739 332 785 903 50 kt 460 937 667 1473 556 1555 518 1227 1410 60 kt 662 1349 960 2121 801 1663 747 1767 2031 We see ABYC's data match our results for a catamaran 30 degrees off the wind. Thus, using equation (3.2) or the associated form gives ample safety margin for most yachts. It is the skipper's responsibility to decide wether these values may be reduced or not for a specific boat and the actual anchoring situation...
I highly recommend that everyone (interested in the numbers) read "Tuning an Anchor Rode" at: http://alain.fraysse.free.fr/sail/rode/forces/forces.htm Excerpted from the article: ... Within these hypotheses, for a 40 ft yacht, equation (3.1) yields the following forces (in daN - to convert into lb, multiply by 2.2): 40 ft Yacht Monohull Catamaran Trimaran Powerboat ABYC's ref. Wind 0̊ 30̊ 0̊ 30̊ 0̊ 30̊ 0̊ 30̊ 10 kt 18 37 27 59 22 46 21 49 56 20 kt 74 150 107 236 89 185 83 196 226 30 kt 166 337 240 530 200 416 187 442 508 40 kt 294 600 427 943 356 739 332 785 903 50 kt 460 937 667 1473 556 1555 518 1227 1410 60 kt 662 1349 960 2121 801 1663 747 1767 2031 We see ABYC's data match our results for a catamaran 30 degrees off the wind. Thus, using equation (3.2) or the associated form gives ample safety margin for most yachts. It is the skipper's responsibility to decide wether these values may be reduced or not for a specific boat and the actual anchoring situation...
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