Chain life in fresh water

[Packer fan]

Hi,
The new to me Nordic tugs 37 has 150’ of 5/16 rusty chain. It is not rusted solid in the locker but it is ugly. My question is, how long does galvanized chain last in fresh water before it gets rusty? I’m tempted to get stainless but then I might reduce the length a bit to save $ and attach some rope.

 

[rslifkin]

In fresh water, it should last a long time. Certainly long enough that I wouldn't spend extra on stainless.

 

[OldDan1943]

Is your chain locker draining quickly?

 

[Packer fan]

I’m assuming so. I guess the question might also be how well the chain locker is ventilated. For that I guess I could open the locker from the cabin.

A second question is how well the chain connector links go through a windless because it sounds like they like to send 5/16 in 92’ buckets and I would probably get 2.

 

[Nomad Willy]

Clean it up and regalvanize.

 

[Woodland Hills]

Rent a small cement mixer and tumble the chain with a few bags of dry sand and/or gravel. Then take a good look at it as you pull it out for pitting, erosion or other wear. If it looks OK after getting it shiny then have it regalvanized. Or try cold galvanizing. If it was me I’d get it clean and then dip it into POR-15 just to see how long it would last...... It would be a fun experiment and a huge mess to do!

Even in freshwater your chain will rust again pretty quickly if you use it a lot. Dragging the chain across the seabed as you swing will wear the Zinc off and allow rust to start as will the points of contact between the links. We wash our chain with seawater and I am sure that stowing steel wet with salt water is not good for it either. But what can you do beyond buying good chain with a safety margin and inspecting it periodically. I repaint my chain markings twice a year, so I check it then.

 

[rslifkin]

I’m assuming so. I guess the question might also be how well the chain locker is ventilated. For that I guess I could open the locker from the cabin.

A second question is how well the chain connector links go through a windless because it sounds like they like to send 5/16 in 92’ buckets and I would probably get 2.

Depending on where you get the chain, you can often get a pail, half drum or drum. Many places will also package any continuous length you want up to a full drum.

If you can order it as a continuous length, that's better than using connector links.

 

[Pete Meisinger]

Woodland Hills has the answer, I never considered it. Great idea.

That chain should literally last forever. If it is bad or rotten it isn't real expensive to replace 40 or 50 feet of it. In fresh water, particularly near you (Lake Michigan) you only need 50 feet of chain, at the most. Use rope beyond that.

pete

 

[Packer fan]

How about 3 strand or double braided attached to the chain
I know double braided lays down better in the locker but the windlass doesn't grip it as well.

 

[rgano]

This is a good site to examine the relative strengths, both working and ultimate breaking, of various chains. Stainless appears to be about 18% weaker than the usually recommended G43 High Test chain for 5/15 inch size. Then there is the cost. If you are considering SS then you are most likely not going to be trying to rehab that junk you inherited with its uncertain quality. Cost effectiveness analysis should guide you to 5/16 G43 (G4, G40, they are all the same). If will last a long time up there in those waters before showing any signs of rust, unless you drag it around over rocks.

 

[Packer fan]

I currently have 5/16 bbb. I didn't think that the g43 would work on the same windlass.

 

[rslifkin]

I currently have 5/16 bbb. I didn't think that the g43 would work on the same windlass.

It depends on the windlass. Some use the same chainwheel for both, some need a different one for bbb vs g43.

 

[kchace]

Actually, 5/16 stainless chain is rated only 2400 lbs and G4 is 3900, so it’s a big difference. Stainless chain is not my cup of tea for a few reasons, but I understand some folks like it.

Ken

 

[rgano]

I currently have 5/16 bbb. I didn't think that the g43 would work on the same windlass.

Check you windlass maker for a G43 wildcat for your windlass.

Check the very similar dimensions of G43 versus BBB here:
https://www.mantusmarine.com/mantus-anchor-knowledgebase/rode-sizing/

You might also ask the manufacturer if the G43 would run through your current wildcat.

 

[sealandsky]

Hi,
The new to me Nordic tugs 37 has 150’ of 5/16 rusty chain. It is not rusted solid in the locker but it is ugly. My question is, how long does galvanized chain last in fresh water before it gets rusty? I’m tempted to get stainless but then I might reduce the length a bit to save $ and attach some rope.

Or you could just say screw it and go for the stainless, if for no other reason that its pretty! I just made that decision and bought 60' of CROMOX 1/2" stainless G43 and had it spliced to 250' of 8 plait for our new Maxwell RC12HD. Almost all of our anchoring is in less than 20', so all of the chain will lay and the rode will secure to our bollard. Thats the plan anyway.

 

[Comodave]

My boat is 26 years old and the chain is original. Looks virtually new.

 

[O C Diver]

The galvanize wears and chips going through the cats paw and dragging across debris on the bottom. Use it enough and you'll have rust appearing. I anchored about 600 times in 8 years of cruising with the majority of the time in freshwater. In spite of always rinsing the chain with freshwater and "end for ending" the chain, it again needs to be regalvanized. The freshwater rinse and removing any debris is probably the best preventitive maintenance you can do for it.

Ted

 

[janice142]

Years ago I tried regalvanizing with a group of friends using a commercial place. I will not do that again! The galvanizing company apparently did not tumble enough after dipping, AND the fellow who picked up didn't check so...

A few years later I was due for more chain. Because the bitter end of about 40' seemed okay, I decided to clean, treat and reuse that portion for my Stop anchor.

I followed the "sure-fire" expertise of an online expert. First I treated/scrubbed with phosphoric acid (ospho, not the green crap that doesn't work) then rinsed with fresh water. Dried thoroughly. Following that I sprayed with galvanizing paint multiple coats.

It rusted anyway, before the chain made it back to Seaweed. Quite frankly, I would replace the chain if at all possible. Because G4 is stronger I would opt for that versus triple-B. Of course these are boats: G4 differs in dimensions from BBB. Good luck.

As long as I'm offering free advice, paint your chain while you've got it out. Above is the chart I used for my 150' of chain. Because I boat/anchor in shallower waters I actually use about 75' of chain maximum. This chart reflects that AND allows me to swap end for end easily.

Yes, I know chosing red-white-blue is not the true nautical old salt version from my youth. It is however for me intuitive. So paint your chain while it is easy.

 

[rslifkin]

Yes, I know chosing red-white-blue is not the true nautical old salt version from my youth. It is however for me intuitive. So paint your chain while it is easy.

I'm no stickler for tradition with things like chain markings. I prefer usable to traditional. Mine is marked with orange and green paint marks, each intended to be individually readable. Green marks to count hundreds, orange marks to count 25 foot increments. So 3 orange is 75 feet, 2 green, 1 orange would be 225 feet.

 

[sealandsky]

Actually, 5/16 stainless chain is rated only 2400 lbs and G4 is 3900, so it’s a big difference. Stainless chain is not my cup of tea for a few reasons, but I understand some folks like it.

Ken

CROMOX lists the break strength of their 5/16 stainless chain at 14,840 lbs.

 

[jleonard]

I'm no stickler for tradition with things like chain markings. I prefer usable to traditional. Mine is marked with orange and green paint marks, each intended to be individually readable. Green marks to count hundreds, orange marks to count 25 foot increments. So 3 orange is 75 feet, 2 green, 1 orange would be 225 feet.

I only marked my chain in 2 places: 50 feet and 100 feet. Never needed to know more than that in my cruising area. Made life simple.
50 in the water, let it set by the wind. 100 coming out, give her a tug in reverse at 800 ish rpm to make sure it's hooked, then let out for the snubber.
Worked for 30 years.