[AdamLein]

Okay hold on a second. I keep reading about how stainless steel is unsuitable for use below the waterline. So how come I see so many stainless anchors?

 

[camaraderie]

Because people are foolish...and the boats with stainless anchors have dock spaces and don't sit for weeks with the anchors on the bottom in the mud.

 

[tager]

Because corrosion doesn't vaporize steel as soon as marketing people would like you to think! And because people have disposable income to spend on shiny things.

 

[sailingdog]

Because they're really pretty...and shiny... and the people who own them are more like raccoons than sailors... and they want pretty, but not very functional anchors.

Stainless steel, when submersed in mud, sand, etc, is going to suffer from oxygen deprivation, crevice corrosion, and other issues. It is going to get scratched up, and suffer from corrosion where ever the finish is marred... and one day, with little or no warning, the anchor's stock or some other important bit is going to snap under load and put your boat up on the rocks...

As Cam points out, the majority of boats that have stainless steel anchors are marina queens, and rarely anchor out, if at all.

 

[brak]

hmm, so if stainles is so poor under these conditions what about aluminum?

 

[AdamLein]

Okay! I thought as much, and yet they seem so ubiquitously marketed, even by respectable manufacturers like Manson and Rocna. Good to know.

 

[AdamLein]

hmm, so if stainles is so poor under these conditions what about aluminum?

My guess is that aluminum is considered too light... my current anchor is a fairly large but aluminum fluke, and it's surprisingly tricky to set. Also I wouldn't trust it under heavy load, especially after a wind shift; if it holds, the torque would probably bend the shank.

 

[tager]

I would get a forfjord anchor if I was in the market. Currently have a danforth from the PO. I also think anchors should be on cables, not chain, but I am crazy.

 

[sailingdog]

It is too light to set well in many conditions... it is also not as strong as a steel anchor in many cases, and can fail if the load is applied to the anchor from the wrong direction.

hmm, so if stainles is so poor under these conditions what about aluminum?

 

[brak]

I use aliminum Fortress and have no issues with it setting. I do wonder about corrosion though.

 

[OsmundL]

It is too light to set well in many conditions... it is also not as strong as a steel anchor in many cases, and can fail if the load is applied to the anchor from the wrong direction.

"Too light"
The 20lb alu anchor is lighter than the 20lb steel anchor, then?

Two excellent anchors are the Rocna and Spade (Rocna being rather too expensive), available in both steel and alu, and I doubt that any of them are troubled with stress.

 

[sailingdog]

There is weight and there is density... the Aluminum anchor's effective weight under water is far less than a steel anchors, due to the lighter density and greater volume of aluminum. Also, the greater surface area of a light aluminum anchor, like the Fortress, often means that it will "kite" if the boat gets moving at all, and not reset.

BTW, can you show me where on the Rocna site they offer an Aluminum anchor. AFAIK, they don't and never have.

"Too light"
The 20lb alu anchor is lighter than the 20lb steel anchor, then?

Two excellent anchors are the Rocna and Spade (Rocna being rather too expensive), available in both steel and alu, and I doubt that any of them are troubled with stress.

 

[OsmundL]

There is weight and there is density... the Aluminum anchor's effective weight under water is far less than a steel anchors, due to the lighter density and greater volume of aluminum. Also, the greater surface area of a light aluminum anchor, like the Fortress, often means that it will "kite" if the boat gets moving at all, and not reset.

BTW, can you show me where on the Rocna site they offer an Aluminum anchor. AFAIK, they don't and never have.

Sorry, SD, I was imprecise. You're right about Rocna, of course - but there are quite a few reasonable copies about.
More important: I wasn't considering the Fortress as the main anchor - to me it is OK as No.2. And the point about weight wasn't literal - I mean to say that you choose the correct anchor - size, weight - for your boat, material already calculated. A great deal of the weight tends to be added in the chain, and the most common mistake is to leave too short a chain in the water.
People should pay more attention to anchor shapes and less to weight unless you anchor on some fairly specific bottom surfaces.

 

[sahara]

Actually, stainless steel, in the right grade, would make a dandy anchor for most rich people. Stainless relies on exposure to oxygen to form a thin protective oxide coating. It can get that oxygen from air or from oxygen dissolved in water. It doesn't like being starved for any significant period of time.

So your shiny anchor is on your bow, you drop it and bury it in mud for a few days, maybe rub some of the oxide off, but then the New York Yacht Club cruise moves on, so you pull it up and voila!, the oxide coating replenishes itself.

But it really should be 316L stainless, and that's really, really expensive, hence the dilemma. Most of the people with enough disposable money to buy a polished stainless anchor just to drag through rocks and mud, are too busy working to actually go use the thing a lot.

I see a lot of them, and have never been tempted, because you really need to buy the all-stainless chain to go with it, and that's just a little much. Plus, I'm not a member of the NYYC.

 

[sailingdog]

Sorry, SD, I was imprecise. You're right about Rocna, of course - but there are quite a few reasonable copies about.

The only real copy of the Rocna, AFAIK, is the Manson Supreme, and I don't believe that is offered in aluminum either.

More important: I wasn't considering the Fortress as the main anchor - to me it is OK as No.2. And the point about weight wasn't literal - I mean to say that you choose the correct anchor - size, weight - for your boat, material already calculated. A great deal of the weight tends to be added in the chain, and the most common mistake is to leave too short a chain in the water.

The Fortress actually suggests you shouldn't have too much chain on it, as may interfere with it setting properly. IIRC, they only recommend up to 15' of chain or so... not the boat length or two that is generally a wise idea and what I recommend.

People should pay more attention to anchor shapes and less to weight unless you anchor on some fairly specific bottom surfaces.

The next gen anchors, like the Spade, Rocna, Manson Supreme, etc, are far better, IMHO, under most conditions than the older designs, like the CQR, Bruce, and Danforth.

The CQR can have serious problems setting, especially on harder bottoms, and when highly loaded, tends to drag far more readily than the next gens. This was clearly seen by the coddling this anchor received in the Sail magazine anchor tests of a few years back.

The Bruce and its copies tend to not set very deeply in many conditions, and often drag and skip. They were really designed for use as very large anchors for stationary oil platforms and large ships.

The Danforth and related designs tend to do poorly in reversing conditions and often have trouble setting, since they can be easily jammed by weed, mud, even beer cans.

 

[brak]

BTW, for holding power and setting ability Fortress consistently comes out on top of all tests I've ever seen. Here is a more recent test of many different anchor types.
www.rocna.com/press/press_0612_wm_ym_testing.pdf

 

[sailingdog]

My problem with the Fortress isn't its holding power...but its inability to reset reliably, especially if the flukes get jammed.

BTW, for holding power and setting ability Fortress consistently comes out on top of all tests I've ever seen. Here is a more recent test of many different anchor types.
www.rocna.com/press/press_0612_wm_ym_testing.pdf

 

[brak]

My problem with the Fortress isn't its holding power...but its inability to reset reliably, especially if the flukes get jammed.

I heard this a number of times but I haven't seen any tests that actually show this happening. I can see the flukes jamming but there are many ways for many anchors to fail. As it stands, in most tests Fortress does not let go at all so really they don't seem to have a chance to try and re-set it.

At the same time, if anchor sets so easily (as Fortress seems to be) - why would it have trouble re-setting (unless jammed)? And what is a frequency of jamming?

 

[sailingdog]

The problem is the lack of weight and large surface area of the flukes. If the boat breaks the anchor out and has any way on or there is a strong current, then the anchor may not get close enough to the bottom to reset. This is especially true if the boat is relatively light and can gain way quickly, like a multihull.

As for jamming, I've seen Danforths jam a fair bit. Weeds, mud, clam shells, etc... can all jam the flukes and prevent them from resetting.

As for tests... they're generally done on relatively clear sandy bottoms... which are unlike a lot of common anchorages. They're generally not littered with beer cans, clams, weeds or anything else likely to jam the flukes of anchors being tested.

I heard this a number of times but I haven't seen any tests that actually show this happening. I can see the flukes jamming but there are many ways for many anchors to fail. As it stands, in most tests Fortress does not let go at all so really they don't seem to have a chance to try and re-set it.

At the same time, if anchor sets so easily (as Fortress seems to be) - why would it have trouble re-setting (unless jammed)? And what is a frequency of jamming?

 

[camaraderie]

Brak...as someone who owned a Fortress Fx85 as a storm anchor...I am a believer in their ultimate holding power being WAY better than anything else their weight...which is why I chose it. I also think it is a poor choice as a primary anchor IF you are in an area with significant reversing tidal currents or in longer term anchoring where wind shifts will require the anchor to reset 180 degrees. That said...it is a fine anchor for anywhere a Danforth would be good and the mud setting makes it perhaps the best in mud. It is lighter and stronger and better than the Danforths of equivilent size.
So...I think you and Dawg both have good points. My point is that cruisers need multiple anchors for different situations.