5/16" or 3/8" Chain

[mako]

"How does one know what the bottom is? The charts have scattered markings, but the bottom changes quickly."

A good fish finder/ depth sounder will allow you to gauge the bottom to some degree, and give warning to a bottom full of boulders or trees (like in the St Johns River).

I would lower my GoPro on a line down to the bottom when in deep water (90ft), plunk it up and down a few times, then bring it up and view. Cheap, but slow because you need to connect to a laptop, but it worked well-enough. It doesn't however allow you to check your anchor's set.

One day I'd like to get a camera with a remote (or cable) feed to a small monitor onboard. That would be ideal for seeing the bottom and doing some easy exploring.

[Jeff on Aurora]

Originally Posted by SVgoinCoastal

Trying to figure out whether to go with 5/16" or 3/8" G4 to go with the 55lb Mantus M2 I'm about to buy. Looking at getting 200ft of chain.* Boat weighs 20,000 dry and I'm wanting this setup to be our better/stronger setup (already have a 35lb CQR, 40' of 1/2" chain + 3/4" nylon rode for normal day stuff) but eventually looking to replace our manual windlass with an electric one and there's a pretty big cost difference between 5/16 and 3/8 there too, so just trying to figure out if 5/16" will be good enough or if i should go with 3/8".* Thanks for any advice.

I have an Island Packet 38, with a dry weight of about 24,000# and a hull not unlike your Irwin. I've lived aboard and cruised for 20 years - entire US east coast, FL Keys, Bahamas, Bermuda. I used to carry 300' of 5/16 HT chain but cut back to 175' + 125' of rope. I'm carrying too much weight in my bow and wanted to reduce hobby horsing.

Acco website says that G43 (HT) 5/16" chain weighs a bit more than 1# per foot and 3/8" weighs about 1.5#. I can't imagine carrying 300' at 1.5 lbs/ft!

As for strength, I can't imagine a scenario where you'd need the stronger 3/8" chain. My 5/16" has held in dozens and dozens of thunderstorm squalls of 50, 60 and even 70 knots. It's also held when we got hit by a waterspout at who-knows-what wind speed because the sensor blew off at 80 kts!

I could see an advantage to 3/8" chain when anchoring in tight harbors on short scope. The extra weight would help hold a nice catenary if you had to skinny down to 4:1 or even 3:1.

If I was going to add more weight to my ground tackle, I'd get an anchor with bigger flukes. I love my trusty 60# CQR, but it will sometimes creep and drag slowly through thin, soupy mud bottoms - think Chesapeake Bay.

So, there are a few data points to add to the mix.



Fair winds,
Jeff

[Kettlewell]

Acco website says that G43 (HT) 5/16" chain weighs a bit more than 1# per foot and 3/8" weighs about 1.5#. I can't imagine carrying 300' at 1.5 lbs/ft!

Yeah, we carried 300 feet of 5/16 down to Colombia and back along with a lot of other crap in the bow locker and there was a noticeable difference offshore in heavy seas. Our boat felt like it wanted to nose dive into big seas and we took a lot of water over the bow. There is definitely a penalty for carrying weight in the bow.

[mako]

That's a lot of chain especially for a light sailboat. When I had my 65 footer it was equipped with 440+ feet of chain. The only time I needed so much rode was anchoring outside Avalon (Santa Catalina) in over 100ft. However I still thought it was ridiculous even for a 50ton vessel.

I think @Aurora above has a good concept and I would throw a hell of a lot more weight into the anchor instead, limited by what will physically fit the roller. Since I didn't have a roller and had to lift the anchor over the railing, I limited myself to a 60lb Danforth and kept the 100lb Dan in the lazarette as a storm backup.

[My Wind Lass]

This post has some great information. Thank you all. I do have a related question though. I am getting ready to launch our new to us boat and I dropped all of our chain out to measure and check for wear. I had to cut off significant chunks of what was probably 300' of chain and I now have about 200' of what appears to be decent chain. I was wondering if there are reliable ways to add links to join existing bits of chain. I found a connecting link at West marine for 3/8 BBB chain that has a safe working load (SWL) of 2750 lb. Does anyone have experience using connecting links and/or should this be avoided totally? I can probably work with 200' of chain while on the US east coast and in the Chesapeake but I will likely need more chain once we get into the Caribbean and beyond. We have a Taswell 49 weighing approximately 44000 lbs. (20+tons) with a Mantus M1 105lb anchor (new). Should I just stick with the 200' until we can afford 300' of new chain or add 100' of new chain with the connecting link?

[David Mathis]

West Coast anchoring is unfamiliar but 200' of chain with the remainder of your needs met with three or eight strand 3/4" (or bigger if you feel it's needed) nylon should keep you in place on the east coast. If you need bigger, the storm is likely so severe that the rode and anchor won't be your primary source of anxiety.

[donradcliffe]

Its the sharp coral that is the problem with nylon rodes. Not so prevalent on the West Coast, but common in the tropics.

[Kettlewell]

I would use the 200 feet plus some nylon. I don't trust most connecting links and they are likely to jam in your windlass when you least need the chain jammed.

[mako]

Originally Posted by donradcliffe

Its the sharp coral that is the problem with nylon rodes. Not so prevalent on the West Coast, but common in the tropics.

When I boated in the Persian Gulf the issue was huge, sharp limestone outcroppings and boulders. The place was littered with them, and miles of nylon line criss-crossing everywhere.

I learned to use regular poly floating line. Obviously not in crowded anchorages or beaches though.

So if you'll be anchoring for a few weeks in remote areas, consider switching over for that period of time instead of using the nylon. I actually used short lengths of chain rather than longer, but had a vasty oversized anchor to compensate.

[sailingharry]

upthread was the suggestion to use 200' of chain, then add nylon. Anohter poster commented on coral. I've not anchored in coral, and when I've need to use more than 200' I've already had a boat with 300' of chain. But, my thought.


200' of chain is 40' deep water at 5:1. 40' deep water with 200' chain and then nylon at 6:1 is 40' of nylon (so just hits bottom). At 5:1 with nylon to the bottom and then all chain yields a depth of 50' (200' chain and 50' of nylon).


My question is, does coral even grow at 50' of depth? And having cruised the St Lawrence River and Newfoundland, I have rarely anchored in more than 50'. Is anchoring at 50' or more common in other areas?


My boat came with 300' of chain in #1, and another 100' in #2. That and 120# of anchors (and 4 crates of canned goods stored in the anchor locker) and my boat isn't exactly in "race trim."

[Tsuru]

I’ve used Crosby C links with good success. They passed through my windlass but some chainwheels are more fussy. IMHO the brand makes a difference and only use Crosby.

https://lifting.com/crosby-missing-l...iABEgKmGfD_BwE

Unless you are headed to the topics I’d probably splice nylon 8 plate to your existing chain.