too big an anchor?

Are there any disadvantages to a seriously oversized anchor (sizing chart wise) given that she fits perfectly on the bow, windlass is rated to handle it with appropriately sized chain etc? Bought a biggin as a storm anchor for full time cruising and now can't see a reason to just keep it as a primary. I've never cruised the Western Caribbean but some of those squalls look spooky...

I don’t see any issues if you can store it and the windlass can haul it. Nothing wrong with big anchors. It will hold better in wnidy conditions.

If it fits, can be handled easily/safely for normal use, and the weight doesn't cause a trim issue, then it's not too big.

You can never be too rich or too thin. Or have too big an anchor.

I don't see a problem, but you probably will need to set it. Often times modest winds and current can pull an anchor into the bottom (I'm sure we are going to hear from someone on this). A big anchor may just lay on the surface and have enough mass to keep the boat in place without digging in. I would want to experiment with it and see if moderate wind or current will set it. I'm in the camp of bigger is better, but think a substantially larger Rocna might not dig in with lite winds the way my 73 pound one does.

Ted

You will be happy when a cold front squall line comes through at 2am gusting to 70 mph.

Too big? [Adopting a Foghorn Leghorn accent] Son, I say son, now there is no such thing as an anchor that's too big -- although it could be your boat is too small. Seriously though, as a third generation boater on Long Island Sound (although not lately), I've always been mystified when I see the "official" lb or kg ratings for various boat sizes. I don't mean to touch off yet another anchor debate, but my boat for example -- 37 nominal, 41 LOA. If I choose a fortress, it says 16 or 23. The 16 looks plain silly hanging from my boy pulpit and the 23 doesn't look much better. I know, I know, it's holding strength, not dead weight, I understand, I'm not anchoring a mooring ball on a chain with an engine block dropped to the bottom of the bay. But just as the poster mentioned above, if your windlass and pulpit and hardware can handle it, as long as you don't create retrieval problems for yourself, I don't know why you couldn't or wouldn't oversize at least a little.

(Of course when you snag that undersea cable and have to cut it loose, bigger usually does mean more expensive...)

O C Diver said:

I don't see a problem, but you probably will need to set it. Often times modest winds and current can pull an anchor into the bottom (I'm sure we are going to hear from someone on this).

Click to expand...

In 4 years of nightly anchoring I have never actually set our 150lb manson supreme.
Never moved an inch either and have seen our fair share of weather, enough that we have deformed 13mm chain - 2 lots in those 4 years.

High Wire said:

You will be happy when a cold front squall line comes through at 2am gusting to 70 mph.

Click to expand...

I can attest to that
Best coin I have spent to date on the boat was a big new gen anchor.

To the OP, I did not choose the size.
I sent to the anchor manufacturer a pic of our vessel, weight and draft, intended usage and cruising area and let them size it.

Or you could just buy a boat that fits the anchor size. Good argument to present to your significant other...

weight of boat and weight of anchor?

Overkill is underrated. Particularly true of anchors.

I've got a 65 pound Mantus, which was on the high side of what was recommended for my size of boat. I thought about going up to the next size just for overkill's sake, but then I decided that if my windlass ever took a dump and I had to reel the thing in by hand, I'd probably have enough of a hard time with the 65 pounder. Hopefully I never find out.

Bigger is better and too much anchor is just right.

First of all it isn’t the size of an anchor that matters ... or it’s weight.
It’s the abilities of the anchor that matters.

And the abilities are far more difficult to ascertain and/or establish numerical performance standards. That’s why there is almost no conversation about real performance. There’s too many variables also.

You can do research and do experiments to get somewhat relative numbers that will help you choose anchors. But still the bottom will vary and to what degree I don’t know. Since we rarely use or test an anchor to breakout we don’t know how the bottom varies for holding power. It’s common knowledge that anchor tests aren’t very accurate. But they are accurate enough to use the information acquired. I do read them and use some of the information to influence my anchor purchases.

IMO The greatest problem w anchor tests is that most tests that feature most all anchors that you may buy new it tells you nothing about how good or bad your old anchor is. And it sure appears to me that most tests that include some older anchors the older anchors seem to do poorly just because they are old. Re holding power many older types have only 1/10th the holding power as the new anchors. I question if they can actually be that bad. But if you’re reading a road test of a new Honda Accord you won’t find them comparing it to a 1980 Honda Accord. So you won’t know what you have to gain ... or loose. The new car may not ride as smoothly and the new car may not have visibility that matches the old car.

Getting back to anchors most all anchor tests tell you how much holding power each anchor has at long scope. That’s it. And few boaters anchor at long scope as in over 6-1. And more importantly most seldom if ever anchor at long scope. But there’s lots of crowded anchorages and deep anchorages and small anchorages. All needing a short scope. But even more important that short scope is setting ability. Perhaps the most important element of anchor performance is setting ability.

Weight in an anchor is good. Holding power in any anchor is good. But size and weight get you nothing ..... directly. But all of it is of value.

What is profoundly best in an anchor is an anchor that does well at everything. Everything well. Short scope/long scope, high holding power/ medium holding power, sets always to sets almost always ..................
Opps ... I may have proved my own point. If it dosn’t set it will hold nothing.
So perhaps the best setting anchor you can find and one that does well at setting and well at everything else but never poorly or badly. Everything in moderation, w no failures and no spectacular abilities.

Maybe the weight of your heavy anchor hanging off the bow will unbalance your boat? Too much weight forward can be a bad thing.

Even on a fairly small boat the extra weight of a larger anchor, within reason, won’t do much to trim. Usually it is the weight of the chain that makes a difference. My anchor weighs about 50 pounds so even a bigger anchor may weigh another 50 pounds. That doesn’t come close to the 300+ pounds that the chain weighs.

Realize that the anchors are not only rated for your size of boat and profile (to the wind), but also has a wind rating. Rocna's are rated to 50 knot winds, Fortress to 30 knot wind.

Some one here once said, "if they don't burst out laughing at how big your anchor appears, its too small," more and more I think this is right.

What ever you do, don’t tell us the size of the anchor. Someone will say it’s too small.
Oh, by the way, you don’t have enough chain.

You’re anchor is usually forward and above your anchor chain rode. Tell a sailboat racer it doesn’t make any difference. Racing sailboats are pretty sensitive on bow weight and trim. A narrow bow section can take even less weight.
All said on my two sailboats I like heavier than normal weight anchors and I sleep better. Although I can notice it affects my steering.

Generally we are not talking sailboats here.

True we are not talking sailboats here but freshalaska has a point.

Sailboats are more pointy in the bow. But they are more pointy in the stern too. They will respond readily to out of trim weight. And that’s perfect for pointing out to us that ground tackle weight has an effect on trim with any boat. I’ve seen many trawlers (in pictures) that are clearly running bow down. The trawler has one pointy end and can’t carry as much weight fwd as aft. But look at that big fat and more or less flat stern. Most easily carry lots of weight. It’s the difference that makes the bow more sensitive to extra weight. So if you’ve got a big bow wave you’re probably running bow down. And if you have trouble steering your bow down boat you may want to check your anchor chain.

And Comodave’s point about the anchor weight having far more effect on anchor performance is well taken. And extra 100lbs of chain helps a bit but having an anchor 100lbs over norm far outweighs the weight advantage of heavy chain.

MikeyG said:

Are there any disadvantages to a seriously oversized anchor (sizing chart wise) given that she fits perfectly on the bow, windlass is rated to handle it with appropriately sized chain etc? Bought a biggin as a storm anchor for full time cruising and now can't see a reason to just keep it as a primary. I've never cruised the Western Caribbean but some of those squalls look spooky...

Click to expand...

We need to know, on a need to know basis, the size and approx weight/displacement of your boat, and the type and weight of the anchor. Otherwise all above is sheer speculation - which we anchor tragics still love to indulge in - but we do like to be able to be a bit more specific if possible, as jokes aside, there is a sort of order of magnitude range.

40 ft, 28000 lbs, dispacement hull. Boat came with 2 cqr's on the front (45 and 35) but an 88# Rocna which I picked up for a very fair price is what I'm considering. A 55 Rocna was my original plan. Boat is very unfussy about trim especially with lighter fuel loads (aft tanks, 400 gal).
My gut tells me to rig it...

Here is a question and I do not know the answer.

Will this big anchor cause the boat to crash through the bottom of waves, in a storm??

Anchors are a compromise too.

As usual Willy has it right. You’re main concern is holding power. Just look at a Aluminum Spade with its small amount of weight poured into the tip but large concave blade area and compare it to a CQR . To get the same holding power the CQR will weigh several multiples of the Spade.
I’ve been running a Rocna for the last 7 years. I’m convinced the 3:1 suffices in almost all circumstances. We go to 5:1 whenever we can but for loose mud don’t increase scope but rather use the Fortress. That’s the other concern. How that design works in the type of bottom where you’re at. When sizing anchors it’s not weight it’s design and effectiveness in the type of bottom.
With trawlers the other concern is trim. Strong believer in all chain. So my concern is total weight of anchor and chain. Due to the diversity of depths and bottoms in our expected cruising grounds want 300’. So that’s a lot of weight. In general displacement hulls do better trimmed slightly bow up in a seaway. Less green water and better behavior when facing the wave train. Given my expected action in heavy weather is to face the seas I don’t want extra weight on the bow. Beyond weight you need to consider the gyradius of the vessel. Trim isn’t just having equal weight at bow and stern nor even equal weight on either side of the the center of buoyancy. Rather the key factor in behavior in a vessel is its gyradius. This is improved by having light ends (both bow and stern) with weight centralized. Educate yourself about the concept of gyradius. It will change how you store things, where you put equipment, how you think about boat designs, and things like anchor choices.
So get the best holding power anchor that your boat can support that won’t impact your trim or gyradius and allow you move a few things safely to assume a slightly bow up trim when necessary.

Only problem I would see is the hassle of carrying its replacement , and bringing it up on deck should it be lost.

Picking the anchor by the windlass ability and what fits is far better than a watch fob mfg catalog.

I must admit a 60H Danforth , while not the largest my hyd windlass would haul never failed , in 2 hurricanes.

The soft mud thing is a good point. In general, design and surface area are all that matters if you find yourself in goop. A bigger anchor pretty much just delays the point (in terms of softness and wind speed) where holding power becomes inadequate and the big Fortress needs to come out.

Big anchors do seem to set more easily and reliably in crappy bottoms though. More weight to push through weeds, and debris on the bottom is smaller relative to the anchor, so it typically has less effect (and less risk of fouling).

On the weight vs trim thing, Hippocampus has some good points there. Of course, sensitivity to weight in the ends or weight distribution in general depends on the hull design. Displacement hulls typically don't like too much weight in the ends. The more rounded the hull and the narrower the ends, the more sensitive it'll be.

Other hull types will be affected differently. A planing hull, for example, will suffer at low speed in ride quality with more weight in the ends, but up on plane, as long as overall weight distribution is good, it will often ride better. The boat with more weight in the ends will have more resistance to pitch changes, which generally means a more comfortable (if a bit wetter) ride in a chop up on plane, where the lift from being on plane is able to damp out the tendency to hobby horse from the weight in the ends providing momentum.

To further expand. Been taught a “proper” boat should have multiple anchors and rodes. Past teaching about storm anchors is probably antiquated as next gens are such a step up that your daily will serve. Still you need one for daily, one for loose mud, a way to anchor bow and stern and a way to run to a tree or other secure point on land. Personally think
For anchors two next gen, a fortress or similar are plenty.
Think an all chain rode with a chain to line as a back up on the bow serve. Then tape or a second chain and line at the stern.
Thing I remain unsure about is whether it’s better to take your anchor(s) off the bow before passage or just lash it down and leave it. See pluses and minuses about either choice.

Absolutely disagree that holding power is your main concern....at least not for the average coastal cruiser.


(Edit: OK, see more reasonable advice than just holding power is important)




Of course it depends...sure for my storm anchor...but not my day to day one hanging from the pulpit. Plus I will have time to make sure it sets.



Almost all tests and those with experience will agree that a danforth style (Fortress included) in a decent bottom has the highest holding power.


Many will also agree it is one of the hardest to get to set.


So motoring along, sometimes in not so great locations....you might have to anchor in a hurry (emergency) and want that anchor to nearly have a mind of its own to set all by its lonesome (if your single engine quits...backing down isn't an option).


Even as my day to day, every night anchor, sure I want it rated for a decent anchorage that may be subject to the occasional thunderstorm squall...but having an anchor big enough for a hurricane? Some boats may be able to carry one does all...but for 1/4 or less the weight, I can carry a Fortress. I can store it anywhere and it will have significantly more holding power as long as I can find a suitable bottom and can get it to set (which should be part of everyone's hurricane planning if they plan to stay in the water and don't have a cane hole that has other tie off points).


To me it's just like securing a boat in a slip for a hurricane.... a CAT 1 can be survived with a decent tie up....once you start going up and in an area of possible high storm surge...no matter how you tie up in a slip unless a perfect floating, wide solo, slip...tie up needs to be different if you want your boat to survive without major damage.



Same with anchoring. Multiple, and or a different anchor(s) that I like for day to day use for BIG storms.

MickeyG I have the same boat as you and you are the original poster.
I have the same aft tankage and hanging on the bow I have a 73 pound Rocna and 330 pounds of chain on the locker. We have lots of deep anchorages in Alaska. Also in the locker is some rope rode and 20 more feet of chain. My boat is a bit bow heavy and I can notice it in the steering. And we are talking apples and apples as boats are the same even if this is a trawler forum. Also I always back down on the anchor jumping up the rpm’s 200 at a time till I get to 2600. And numerous times the anchor will drag if less than a 5 to 1 scope. Often the anchor will hold to 2200 rpm but not 2600 with much less than 5 to 1.