Have you ever broken your chain?

[Kettlewell]

I am curious if anyone has ever snapped their anchor chain in use, and what the materials and circumstances were? Not interested in hearing about something you heard, unless it is from a very trustworthy source. There are often debates about this or that sized or grade of chain, but frankly it seems like most everything that people use keeps on working for a good long time. I imagine any chain will eventually corrode to the point of being unuseable, but I have never broken any or apparently even strained it enough to damage it, despite having anchored in some lesser hurricanes.

[virginia boy]

Im giving this thread a bump to the top because I'm very interested to find out too.

I've never even heard of anyone breaking anchor chain.

[s/v Jedi]

I never broke my G7 chain but replaced it once with slightly deformed links after a major hurricane. It still passed the windlass without trouble so wasn't too bad.

But I have witnessed broken chain with boat adrift in Curacao. The cause was electrolysis eating away at the chain.

=> This is why I always repeat that a windlass should not be grounded, i.e. the housing not connected tobattery negative. The windlass motor should have an insulated connection for battery negative. Also, others oarts and metal that make contact with the chain (chainstopper, bowsprit, bobstay etc) should not be grounded. The anchor chain should be electrically "floating" when at anchor.

cheers,
Nick.

[HopCar]

I've seen badly worn anchor shackles that if they were not replaced would have broken. No I've never seen a chain break under load while anchored. Doesn't mean it can't happen but I think you'd see wear and replace it before it happened. I guess if you used a chain much smaller than recommended for your size boat you could break it. Don't forget that the recommended working load on everything in your anchor rode is probably only 1/4 or less than the tensile strength. You've got a big margin.

[Kettlewell]

How do you know the cause was electrolysis, and how long had the boat been there at anchor?

[Greggegner]

A Friend broke theirs...bad storm, the were new to cruising and didn't use a snubber. Wind pull the chain tight, they started to drag and when the anchor caught the chain parted.

[Kettlewell]

HopCar, when I rode out Gloria at anchor I was using 5/16 Proof Coil with a suggested working load of around 1900 lbs, and the ABYC tables suggest storm loads will be up to 1800 lbs. for a low-30 foot boat. I suppose G40 chain is more like 2400 on the working load, but it certainly seems that someone can get up close to the load levels the chain was designed for. Of course breaking strength is higher--double I think.

[s/v Jedi]

Originally Posted by Kettlewell

How do you know the cause was electrolysis, and how long had the boat been there at anchor?

I measured it. There was a 3V DC differential between battery negative and anchor chain. Another boat anchored nearby had the same and some links had lost half the material. Both boats had a bonding wire attached to the windlass (we had that too, which is why I always notice it)

This was all within 2-4 weeks anchored at the same spot. The potential can differ, but the ground potential from an anchor buried in the seabed is different than that of a dynaplate or other metal submerged near the surface. A current will run as the result of that.

[boatman61]

Chain breakage is generally through rust and wear at each end of the link.. if it gets that far.. hate to see the rest of the boat..
Have had the shaft of a CQR snap on me though..

[foggysail]

No and I think most chain sizes used are gross overkill. For example, I have 5/16" G40 only because the gypsies offered by Maxwell did not include a 1/4" G40 gypsy for the particular windlass I purchased.

No way will most cleats, chocks along with bow structures hold up to the breaking strength of 7750 lbs rated for 1/4" G40!!!

[sww914]

Good question!

[HopCar]

Kettelwell, It sounds like you have the correct strength chain. You approached the working load limit but you were no where near breaking it. The breaking strength of 5/16 proof coil is about 7500 pounds.
The working load limit on 5/16 G4 chain is about double that of proof coil.

[Kettlewell]

OK, we've heard of one chain breaking due to electrolysis (who knew?) and an anecdote of the chain breaking on someone else's boat, but no firsthand experiences. Anyone?

By the way, I now use 5/16 G40 on a 38-foot boat, but the max wind speed it has seen is maybe only 60 knots for a brief period.

[s/v Jedi]

I get the feeling that only damaged or weakened chain breaks... good thing to check on for other reports.

[Kettlewell]

Found an earlier thread on this with limited reports--they are mostly second-hand ones.