Reality check on chain size

[Haloo]

My boat is a bit of an outlier on this forum. Here are some particulars:

Power: 2 300hp Mercury outboards
Length: 35 feet tip of the bow pulpit to back of the tipped down engines
Weight: 11,675 pounds (5.8 tons, 5.3 metric tons) fully loaded with fuel, water, provisions, etc...
Hull type: Planing
Anchor: 33lb Vulcan (As per the Rocna fitment guide)
Rode: 30 feet of 1/4” chain, and 270 feet of 1/2” three strand line.
Other: While my boat seems like it is on skates when at rest in the wind, the overall sail area of the boat is relatively small compared to trawlers and tugs.

The Rocna fitment guide calls for 5/16” chain for a 33lb Vulcan. Do I need to upsize my chain?

And/or should I increase the length of chain? I wish I had started with a bit more, but how what length would be best?

Thanks!

(I love this forum.)

 

[DavidM]

Depending on where and how deep you anchor, your rode may be ok. But 1/4" chain is a little small, particularly if it is BBB. If it is HT G4 or G43 then it is probably ok.

If you anchor deep or in exposed places then I would go with much more chain. But do you have a windlass? Pulling up a 33 lb anchor and 30' of chain isn't much of a problem, but pulling up 100' of chain in 50' of water will be.

David

 

[rslifkin]

A bit more chain won't hurt. For chain size, 1/4" g43 should be fine. I doubt you could readily overload it with that boat.

 

[Frosty]

This brings up a question I have had recently about sizing ground tackle:

Back in the day on sailboats, I always used the Pardeys' chart which was all about *windage* not weight. You calculated the windage of your boat and then looked at their charts as compared to what strength of wind you wanted to prepare for. Now I see that people mostly go by weight. But isn't windage more important? Or no?

***********

5/16" "sounds" slightly large to me for your boat with relatively low windage, but one thing about 1/4" HT chain (at least last time I was rode shopping; granted that was many, many moons ago) is that I've never been able to find a US made galvanized high-test shackle to fit it (HT shackles start one size larger than what fits). That can make the shackle the weak point as compared to the chain or typical rope rode. As long as that is strong enough then fine, but it always annoyed me to have the shackle be the weak point.

Maybe there is some clever way to do it with high tech cordage nowadays, or maybe people are using stainless shackles now (?) (I always stuck with just galvanized metal and rope in my rode in past days.)

Example:

---ACCO G-4 1/4" chain = Working Load Limit 2,600#

---1/2" Yale Brait 8-plait line = WLL 1,660# or...
---5/8" Yale Brait 8-plait line = WLL 2,440#

--- Crosby 5/16" red pin G-209 shackle (5/16" fits in 1/4" chain) = WLL 1,500#

(This same problem doesn't happen with 5/16" chain because the HT shackle (G-209A) is available starting in a 3/8" size, which is what fits in 5/16" chain. So ACCO HT 5/16" chain WLL = 3,900#, and 3/8" G-209A shackle WLL = 4,000# If you were stuck with the red pin shackle only, then it would have the same problem at WLL = 2,000#)

I'll be reading with interest.

BTW: OP, I think your boat is really neat!

 

[rslifkin]

Some people have had a one size larger end link put on chain to alleviate the problem.

 

[Nomad Willy]

I think you’re good to go.

 

[Frosty]

Some people have had a one size larger end link put on chain to alleviate the problem.

How is that done so that it's "kosher"? Maybe it's always fine, but I oftentimes see people advise against joining two sections of chain that way. Maybe that's more about going through the windlass gipsy well? (Obviously not a problem at the shackle point.) I wasn't sure if it was that or if it was because it somehow could not be done up to snuff.

 

[Haloo]

This brings up a question I have had recently about sizing ground tackle:

Back in the day on sailboats, I always used the Pardeys' chart which was all about *windage* not weight. You calculated the windage of your boat and then looked at their charts as compared to what strength of wind you wanted to prepare for. Now I see that people mostly go by weight. But isn't windage more important? Or no?

***********

5/16" "sounds" slightly large to me for your boat with relatively low windage, but one thing about 1/4" HT chain (at least last time I was rode shopping; granted that was many, many moons ago) is that I've never been able to find a US made galvanized high-test shackle to fit it (HT shackles start one size larger than what fits). That can make the shackle the weak point as compared to the chain or typical rope rode. As long as that is strong enough then fine, but it always annoyed me to have the shackle be the weak point.

Maybe there is some clever way to do it with high tech cordage nowadays, or maybe people are using stainless shackles now (?) (I always stuck with just galvanized metal and rope in my rode in past days.)

Example:

---ACCO G-4 1/4" chain = Working Load Limit 2,600#

---1/2" Yale Brait 8-plait line = WLL 1,660# or...
---5/8" Yale Brait 8-plait line = WLL 2,440#

--- Crosby 5/16" red pin G-209 shackle (5/16" fits in 1/4" chain) = WLL 1,500#

(This same problem doesn't happen with 5/16" chain because the HT shackle (G-209A) is available starting in a 3/8" size, which is what fits in 5/16" chain. So ACCO HT 5/16" chain WLL = 3,900#, and 3/8" G-209A shackle WLL = 4,000# If you were stuck with the red pin shackle only, then it would have the same problem at WLL = 2,000#)

I'll be reading with interest.

BTW: OP, I think your boat is really neat!

We recently enclosed the cockpit with canvas and some cleverly designed windows. This surely increases our sail area while doubling our living area. But we are so low to the water compared to most of the boats on this forum I doubt windage is too much of a problem.

The boat was delivered to us with the current anchor rode including a swivel, minus a shackle. I installed a 3/8” stainless steel shackle to take lateral stress off the swivel. This shackle was the only one I could lay my hands on quickly. And as our immediate goal is to practice anchoring in calm circumstances I think it will do for now. I’m trying to find out the specs on the chain, swivel, and three strand from the folks where we purchased the boat.

It never occurred to me that I wouldn’t be able to find a 3/8” HT galvanized shackle. Then again, I’m on the very steep part of the learning curve with regard to ground tackle and anchoring technique.

We’ve dealt with a lot of family tragedy since we started searching for and purchasing our boat. So we are a bit behind with regard to filling in knowledge gaps. Thank goodness for this forum!

And thanks for the compliment on our boat. We love it.

 

[rgano]

My boat is a bit of an outlier on this forum. Here are some particulars:

Power: 2 300hp Mercury outboards
Length: 35 feet tip of the bow pulpit to back of the tipped down engines
Weight: 11,675 pounds (5.8 tons, 5.3 metric tons) fully loaded with fuel, water, provisions, etc...
Hull type: Planing
Anchor: 33lb Vulcan (As per the Rocna fitment guide)
Rode: 30 feet of 1/4” chain, and 270 feet of 1/2” three strand line.
Other: While my boat seems like it is on skates when at rest in the wind, the overall sail area of the boat is relatively small compared to trawlers and tugs.

The Rocna fitment guide calls for 5/16” chain for a 33lb Vulcan. Do I need to upsize my chain?

And/or should I increase the length of chain? I wish I had started with a bit more, but how what length would be best?

Thanks!

(I love this forum.)

You are right in my size (35' LOA and 12,000 pounds), and I have 195 feet of 1/4" G4 chain backed up by 120 feet of 1/2" braided nylon connected by a Mantus swivel to a 35-pound SuperMax anchor. The strength of the G4 is adequate to the needs of the boat. While anchor makers may specify rode (chain and or fibrous) to handle the maximum holding power of their anchor in specific bottoms, what you and I want is a rode adequate to handle the loads exerted by the vessel at the other end of the rode, and our boats with their lower light weight and low profile will exert far less force than a high-sided trawler with its associated tophamper.

 

[Haloo]

Depending on where and how deep you anchor, your rode may be ok. But 1/4" chain is a little small, particularly if it is BBB. If it is HT G4 or G43 then it is probably ok.

If you anchor deep or in exposed places then I would go with much more chain. But do you have a windlass? Pulling up a 33 lb anchor and 30' of chain isn't much of a problem, but pulling up 100' of chain in 50' of water will be.

David

Yes, we have a windlass. I think I might stick with the 30 feet of chain for our anchoring learning stage. Then I might be a good idea to have a longer chain, maybe 75 to 100 feet. Right now our anchor outweighs our chain. (I’m assuming this isn’t an issue.) I’m going to use RGANO’s idea for re-braiding the last 6 feet of the anchor bridle I built so I can tie off to line or chain.

 

[Haloo]

You are right in my size (35' LOA and 12,000 pounds), and I have 195 feet of 1/4" G4 chain backed up by 120 feet of 1/2" braided nylon connected by a Mantus swivel to a 35-pound SuperMax anchor. The strength of the G4 is adequate to the needs of the boat. While anchor makers may specify rode (chain and or fibrous) to handle the maximum holding power of their anchor in specific bottoms, what you and I want is a rode adequate to handle the loads exerted by the vessel at the other end of the rode, and our boats with their lower light weight and low profile will exert far less force than a high-sided trawler with its associated tophamper.

Thanks Rich! It is great to hear from an experienced boater with a similar sized boat. I’m going to try to figure out how much chain I can fit in my locker. I’m assuming less than the 270’ of 3 strand in there now.

 

[kchace]

My boat is a bit of an outlier on this forum. Here are some particulars:

Power: 2 300hp Mercury outboards
Length: 35 feet tip of the bow pulpit to back of the tipped down engines
Weight: 11,675 pounds (5.8 tons, 5.3 metric tons) fully loaded with fuel, water, provisions, etc...
Hull type: Planing
Anchor: 33lb Vulcan (As per the Rocna fitment guide)
Rode: 30 feet of 1/4” chain, and 270 feet of 1/2” three strand line.
Other: While my boat seems like it is on skates when at rest in the wind, the overall sail area of the boat is relatively small compared to trawlers and tugs.

The Rocna fitment guide calls for 5/16” chain for a 33lb Vulcan. Do I need to upsize my chain?

And/or should I increase the length of chain? I wish I had started with a bit more, but how what length would be best?

Thanks!

(I love this forum.)

If your chain is NOT G43 then it’s too weak. For example, 1/4” BBB chain has a working load limit of 1300lbs. 1/4” G43 chain has a much better working load limit of 2600lbs.

Ken

 

[O C Diver]

I used 1/4" chain for many years on my 35' Bruno and Stillman charter boat. With customers and all the scuba gear, it weighed more than yours. Because we were grappling shipwrecks, my scope was less than 1.4:1. Never had an issue with the chain, but did stretch some 1/2" 3 strand nylon to less than 3/8" in a 2 knot current.

As long as you have atleast 20' of rope out to act as a snubber, can't imagine you will have a problem.

Ted

 

[Frosty]

It never occurred to me that I wouldn’t be able to find a 3/8” HT galvanized shackle. Then again, I’m on the very steep part of the learning curve with regard to ground tackle and anchoring technique.

Just to clarify, 1/4" G4 (high test) chain accepts a 5/16" shackle. Crosby (my preferred shackle source) does not make a HT shackle in 5/16" -- they only start at 3/8". Others may?

Crosby do make their standard "red pin" galvanized shackle in 5/16", but that only has a WLL of 1,500#. NOT saying that's not good enough but just something to be aware of since the chain has a WLL of 2,600# (weakest link and all that). If they made the 5/16" in HT it would meet the WLL of the 1/4" G4 chain (or be in the ballpark anyway).

(When you get up to 5/16" G4 chain, then the 3/8" HT shackle that it accepts is about the same WLL as the chain.)

 

[Haloo]

I used 1/4" chain for many years on my 35' Bruno and Stillman charter boat. With customers and all the scuba gear, it weighed more than yours. Because we were grappling shipwrecks, my scope was less than 1.4:1. Never had an issue with the chain, but did stretch some 1/2" 3 strand nylon to less than 3/8" in a 2 knot current.

As long as you have atleast 20' of rope out to act as a snubber, can't imagine you will have a problem.

Ted

Thanks Ted. The anchor bridle I made from 1/2” is about 30’ overall in length. With the last 6’ re-braided as RGANO has suggested it sounds like I should be fine even if I tie off the bridle directly to the chain.

 

[rgano]

Just to clarify, 1/4" G4 (high test) chain accepts a 5/16" shackle. Crosby (my preferred shackle source) does not make a HT shackle in 5/16" -- they only start at 3/8". Others may?

Crosby do make their standard "red pin" galvanized shackle in 5/16", but that only has a WLL of 1,500#. NOT saying that's not good enough but just something to be aware of since the chain has a WLL of 2,600# (weakest link and all that). If they made the 5/16" in HT it would meet the WLL of the 1/4" G4 chain (or be in the ballpark anyway).

(When you get up to 5/16" G4 chain, then the 3/8" HT shackle that it accepts is about the same WLL as the chain.)

Look here: https://tinyurl.com/y2ffe3p6

You will find Columbus McKinnon 3/8 and 5/16 CHAIN shackles in 2000 and 3000 working load limits in galvanized or other surface treatments listed.

 

[Haloo]

Between this thread and the Swivel thread I’ve gotten quite an anchor rode education. Thankfully, further online reading has revealed that G4, G40, and G43 all refer to the same grade of chain...clearing up a lot of confusion for me.

The more I read, and listen to opinions here, there appears to be not a lot of downside to a bit of overkill in my anchoring system. As a new boater I think the peace of mind will be worth it.

 

[Frosty]

Look here: https://tinyurl.com/y2ffe3p6

You will find Columbus McKinnon 3/8 and 5/16 CHAIN shackles in 2000 and 3000 working load limits in galvanized or other surface treatments listed.

Thank you! I didn't immediately see where to buy one or where manufactured, but this is a good lead which I will investigate. Much appreciated.

(And here I was going to solve the problem by getting a boat big enough for 5/16" chain/3/8" shackle :lol

BTW, the link is to Columbus McKinnon's web page in case anyone would like to know before clicking.

Haloo: I like to anchor out, and to feel secure. Some possible downsides are these:

1) No windlass
2) You own a windlass that has a specific gipsy (some can be changed tho).
3) Fit (distance from roller to gipsy, bow clearance for anchor toe, etc.
4) Weight in the bow (not ideal on a lighter boat - just be sure you can still get bow up in following seas as you don't want permanent bow steer).

Within those constraints, I see no reason not to go for a robust and well-put-together ground tackle system. I would.

 

[Haloo]

Thank you! I didn't immediately see where to buy one or where manufactured, but this is a good lead which I will investigate. Much appreciated.

(And here I was going to solve the problem by getting a boat big enough for 5/16" chain/3/8" shackle :lol

BTW, the link is to Columbus McKinnon's web page in case anyone would like to know before clicking.

Haloo: I like to anchor out, and to feel secure. Some possible downsides are these:

1) No windlass
2) You own a windlass that has a specific gipsy (some can be changed tho).
3) Fit (distance from roller to gipsy, bow clearance for anchor toe, etc.
4) Weight in the bow (not ideal on a lighter boat - just be sure you can still get bow up in following seas as you don't want permanent bow steer).

Within those constraints, I see no reason not to go for a robust and well-put-together ground tackle system. I would.

More good points to consider. Thanks! I will add some weight to the bow of my boat and see what the effect is before adding more chain.

My windlass seems to handle the 30’ of chain I currently have with no problem.

 

[FF]

"The anchor bridle I made from 1/2” is about 30’ overall in length."


The line should be short enough to not foul the prop should it go overboard.

 

[Haloo]

"The anchor bridle I made from 1/2” is about 30’ overall in length."


The line should be short enough to not foul the prop should it go overboard.

Thank you. It’s about 30 feet from the hawseholes to the props. But the first 4 feet of bridle goes from the center cleat to the hawseholes. So I should be okay. I’ll check all the dimensions just to be on the safe side.

 

[rslifkin]

Having the bridle short enough not to hit the props is ideal. But when it comes down to it, having it be long enough to provide adequate stretch while using line thick enough not to suffer early fatigue failure matters more.

 

[Mako]

If your chain is NOT G43 then it’s too weak. For example, 1/4” BBB chain has a working load limit of 1300lbs. 1/4” G43 chain has a much better working load limit of 2600lbs.

We need to think about the application. OP's boat is not a bluewater trawler or extended cruiser. (I'm assuming) he enjoys fair weather fishing and cruising in his boat. Chances of having to weather a hurricane or 60 knot storm - probably zero. Chances of ever anchoring in winds over 30 knots - most likely never.

Rereading the original post, the issue seems to be more about how to reduce sailing about at anchor, not about whether his anchor and rode are strong enough.

It's tough to tackle the sailing issue. Rig a riding sail - not practical. Upsizing nylon rode will do virtually nothing. All chain 1/4" will help a lot but adds cost and weight.

My last boat was light and was all rope rode (only 3ft of heavy chain). What helped me was to attach the rode to the forward side cleat, not the bow cleat. The springline cleat. Let your boat hang off the rode from about 20° off center and see if that helps reduce sailing as you're presenting an asymmetrical profile to the wind.

 

[rsn48]

In "ordinary" conditions your anchor set up is fine. But boating in the PNW, Coastal BC and Alaskan Panhandle can bring on more challenging conditions. If you are new to boats, boating and in particular your current boat, anchoring will probably be on the conservative side, averaging a 30 foot depth in protected waters with a decent bottom.

But when the plague ends, you might very well want to come up into BC and Alaskan waters and occasionally you will be anchoring in much deeper water. In summer average protected conditions, you will be fine but should you develop wander lust then I would definitely lengthen your chain portion of your rode to at least one hundred feet. You might very easily find yourself anchored in 70 feet or deeper water and the weight of the chain will definitely help in maintaining a decent angle of rode to anchor. You might easily find yourself with a 3:1 or less rode ratio, again more chain definitely helps.

I would suggest staying with what you have then supersizing your chain once you know you are going to hit some more challenging conditions if you start travelling north. With smaller boats, using all chain affects bow performance, on the larger trawlers not so much. So for us smaller boat guys, I prefer a combo of line and chain and at least 100 feet of chain for deeper anchorages.

 

[Haloo]

In "ordinary" conditions your anchor set up is fine. But boating in the PNW, Coastal BC and Alaskan Panhandle can bring on more challenging conditions. If you are new to boats, boating and in particular your current boat, anchoring will probably be on the conservative side, averaging a 30 foot depth in protected waters with a decent bottom.

But when the plague ends, you might very well want to come up into BC and Alaskan waters and occasionally you will be anchoring in much deeper water. In summer average protected conditions, you will be fine but should you develop wander lust then I would definitely lengthen your chain portion of your rode to at least one hundred feet. You might very easily find yourself anchored in 70 feet or deeper water and the weight of the chain will definitely help in maintaining a decent angle of rode to anchor. You might easily find yourself with a 3:1 or less rode ratio, again more chain definitely helps.

I would suggest staying with what you have then supersizing your chain once you know you are going to hit some more challenging conditions if you start travelling north. With smaller boats, using all chain affects bow performance, on the larger trawlers not so much. So for us smaller boat guys, I prefer a combo of line and chain and at least 100 feet of chain for deeper anchorages.

This pretty well sums up my situation. My wife and I definitely want to head north (Desolation Sound, the Broughtons, etc...post pandemic) when we’ve gained more experience anchoring.

Our anchor locker can probably handle about 200 feet of 1/4 inch chain (about 150 pounds) and 100 feet of 1/2 inch three strand line. Our windless can handle 1/4 inch chain.

When you say “supersizing” our chain are you referring to length, chain size, or both?

 

[Haloo]

We need to think about the application. OP's boat is not a bluewater trawler or extended cruiser. (I'm assuming) he enjoys fair weather fishing and cruising in his boat. Chances of having to weather a hurricane or 60 knot storm - probably zero. Chances of ever anchoring in winds over 30 knots - most likely never.

Rereading the original post, the issue seems to be more about how to reduce sailing about at anchor, not about whether his anchor and rode are strong enough.

It's tough to tackle the sailing issue. Rig a riding sail - not practical. Upsizing nylon rode will do virtually nothing. All chain 1/4" will help a lot but adds cost and weight.

My last boat was light and was all rope rode (only 3ft of heavy chain). What helped me was to attach the rode to the forward side cleat, not the bow cleat. The springline cleat. Let your boat hang off the rode from about 20° off center and see if that helps reduce sailing as you're presenting an asymmetrical profile to the wind.

Yes, these are issues I want to address as well. I don’t want to freak fellow boaters out when the current and wind shift and our boat slides quickly/erratically in response. I don’t want to be freaked out either. I will experiment with your idea about cleating off to a side cleat.

We also plan to head up into some deeper anchorages than we typically get in the South Puget Sound, e.g. Desolation Sound, the Broughtons, etc...). Would 150 pounds of chain in the rode locker make a huge difference in our boat? We get up on plane in about 5 or 6 seconds currently. Twin three hundred horsepower V8 Mercurys (600hp total) give a pretty good push.

 

[Mako]

Would 150 pounds of chain in the rode locker make a huge difference in our boat?

Probably not but best way to tell is just use people weight. Wife 110lbs. Teen son 150lbs. You 200lbs. Etc.

Movable weights you can set up in the bow and see how the boat reacts. But also check how the boat responds when porpoising into big seas and also swells bow-on. Loss of buoyancy and nose diving can be dangerous.

 

[Nomad Willy]

Mako wrote;
“ We need to think about the application. OP's boat is not a bluewater trawler or extended cruiser. (I'm assuming) he enjoys fair weather fishing and cruising in his boat. Chances of having to weather a hurricane or 60 knot storm - probably zero. Chances of ever anchoring in winds over 30 knots - most likely never.

Rereading the original post, the issue seems to be more about how to reduce sailing about at anchor, not about whether his anchor and rode are strong enough.

It's tough to tackle the sailing issue. Rig a riding sail - not practical. Upsizing nylon rode will do virtually nothing. All chain 1/4" will help a lot but adds cost and weight.

My last boat was light and was all rope rode (only 3ft of heavy chain). What helped me was to attach the rode to the forward side cleat, not the bow cleat. The springline cleat. Let your boat hang off the rode from about 20° off center and see if that helps reduce sailing as you're presenting an asymmetrical profile to the wind”.

I agree completely.

 

[rsn48]

When you say “supersizing” our chain are you referring to length, chain size, or both?

I was referring to length of the chain and not size. The previous owner had a Lewmar windless installed along with new chain (100 feet) and line (250 feet) so with everything I have done in refit, I ignored the rode and windless since it had been just added prior to me purchasing the boat.

I notice in the Rocna chart, (see below) a chain of 3/8ths is suggested. Again to repeat myself, stick with what you have until you are anchoring in deeper water then acquire a longer chain (using your current chain for you backup anchor).

https://www.google.com/search?q=roc...BAgMECM&biw=1920&bih=937#imgrc=Rj74OUPvqYpVYM

 

[jhall767]

Mako wrote;
“ We need to think about the application. OP's boat is not a bluewater trawler or extended cruiser. (I'm assuming) he enjoys fair weather fishing and cruising in his boat. Chances of having to weather a hurricane or 60 knot storm - probably zero. Chances of ever anchoring in winds over 30 knots - most likely never.

Rereading the original post, the issue seems to be more about how to reduce sailing about at anchor, not about whether his anchor and rode are strong enough.

It's tough to tackle the sailing issue. Rig a riding sail - not practical. Upsizing nylon rode will do virtually nothing. All chain 1/4" will help a lot but adds cost and weight.

My last boat was light and was all rope rode (only 3ft of heavy chain). What helped me was to attach the rode to the forward side cleat, not the bow cleat. The springline cleat. Let your boat hang off the rode from about 20° off center and see if that helps reduce sailing as you're presenting an asymmetrical profile to the wind”.

I agree completely.

One step better than a cleating to one side is a bridle where you cleat to both sides. Also works as a snubber if your rode is chain. Set from the spring cleats it also reduces your swing arc distance.

You can make your own or buy one.

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