tips for anchoring in grass

[wtmf]

ground tackle could you post some photos of the Excel anchor? thanks

[groundtackle]

Wtmf, I’ve 2504 pics. It won’t load them all.
Is there a particular angle you might like to see?
Chris

[groundtackle]

Originally Posted by noelex 77

Weed is one of the few substrates that modern anchors still struggle with. As it is a common substrate, an anchor’s performance in weed is extremely important.

Unfortunately, evaluating weed performance is very difficult. I have found when observing anchor performance underwater that an anchor can look well set (because it is buried in the weed) but if you reach down and feel what is happening, often the anchor tip is being held by the weed rather than the far more secure set of penetrating the weed into the substrate below& the weed.

User reports are also problematic. Thick weed can actually provide reliable holding in moderate winds even with anchor designs that cannot penetrate the weed roots. However, in strong winds an anchor just holding onto the weed will not be reliable.

One thing to note is that even if the substrate is only partially weedy, an anchor that drags will frequently pick up heaps of weed. Sometimes weed is incorrectly blamed for the dragging incident. Conversely, convex plow anchors frequently shed weed when they are pulled off the bottom, so they can sometimes give little indication of weed even if this was the cause of the drag (although this depends on the type of weed). Have a look at the photo of this Delta underwater. All this weed is no longer attached to the bottom. It has been pulled out as the anchor dragged. However, when raised the owner would have little comprehension of how cloged the anchor had become when it was actually on the seabed.

Underwater:


Surface:


The best weed anchors have a thin, sharp toe. Anchors with ballast in the toe such as the convex plow anchors have a tough time forcing this thick ballast through the weed roots.

Bigger certainly helps. For the most part, a small anchor fitted to a smaller boat will perform in a very similar way to larger anchor of the same design fitted to correspondingly large boat, but in weed this relationship tends to break down. The weed roots do not change size.

Finally, technique is important in weed. It is vital that no force is placed on the anchor until an adequate scope is reached. So after dropping the anchor try and lay the chain in straight line but do not risk moving the anchor by placing undue force on the anchor until adequate scope is reached.

Noelex, All anchors regardless of the generation struggle in certain substrates and weed is one. Underground fast is the answer.
If you can reach down and feel the toe that is not good, its obviously is not working at all.
Holding simply into or onto weed is just wrong and never should happen unless that’s all you have. An actual reverse test to impress the predictable loads after any drop is logical.
As you say judging any set by observing the amount of seabed attached, grass or lack of is a poor indication of the set or it’s potential. More muck attached could actually indicate an uncontrolled or unbalanced fluke surface with a tendency not to re-enter the bottom. As clean as the Excel or a delta comes up, they won’t show much info. A clump of salad is howerever a good indicator of a drag on any anchor and at least something to observe.
Thin sharp toe.. nope. You couldn’t be more wrong. In fact having the proper progression in splitting the substrate aside in all directions is very important. Obviously a premium is placed on the up or seabed compression side being critical. Staying level as the anchor dives is very important as it finds different levels of hardness, like rocks within soft. They must be able to quickly reorient. I’ll add that when a roll bar has served it perpose to get the fluke in proper position it’s detrimental to the set, an anchor needs to be clean of all appendages. A thin sharp toe can in fact be detrimental as the backside or low pressure can create a slurry or turbulent area behind the fluke causing the soil to liquify. It’s all about minimizing soil disturbance while driving the anchor to a maximum depth.
Weed or kelp is so soft in comparison to a good controlled diving attitude of a metal anchor under load. It’s no match, whatever size a grass it is.
I don’t buy into the bigger argument. Little ones can find their way thru a curtain, sometimes easier. As long as the anchor is appropriately sized, Better is better.
I certainly agree that when setting in weed you must slow down and give them that chance to settle in, grab a handful of anything without finding the bottom is chancy.
I’m also quite sure if the intention is to assimilate an Excel with a Delta its just a lack of actual hands on experience. Well proven the Excel has double the holding power for the same size.
Chris

[groundtackle]

GILow and Painted Sky’s, thanks for the Marsh info. The hard stuff under grass is very difficult and great to see the development to suit your backyard. I’ve found similar but rare up here in the PNW and around most of the north west coast. Mexico has some of those bottoms. I’d like to play with one.
The springs they make are kinda cool too.
Chris.

[GILow]

Originally Posted by groundtackle

GILow and Painted Sky’s, thanks for the Marsh info. The hard stuff under grass is very difficult and great to see the development to suit your backyard. I’ve found similar but rare up here in the PNW and around most of the north west coast. Mexico has some of those bottoms. I’d like to play with one.

The springs they make are kinda cool too.

Chris.

Rumour around the local yachties is that the Marsh design was brought here by Italian fishermen. If that’s the case I assume there are bits around Italy that suffer the same seagrass issues we face. Some of the Med Cruisers on the forum may know more.

[noelex 77]

Originally Posted by groundtackle

Underground fast is the answer.

Agreed. I should have mentioned the speed or distance taken to set. Anchors that are good in weed are almost always designs that set rapidly. You can look at my photos and see which designs set most rapidly. The difficulty and setting distance of penetrating hard sand has a good correlation with the difficulty and setting distance of penetrating weed.

Originally Posted by groundtackle

If you can reach down and feel the toe that is not good, its obviously is not working at all.
Holding simply into or onto weed is just wrong and never should happen unless that’s all you have. An actual reverse test to impress the predictable loads after any drop is logical.

Also agreed. But this is not the way anchors work underwater. Over 90% of anchors I see in thickish weed are holding in the weed itself without any penetration into the substrate below. An anchor holding in this manner will generally hold full reverse from a yachts engine. It will also hold up to around 25-30 knots of wind (depending on the weed). However to hold in strong wind the anchor must penetrate (or at least grip in the case of weed over rock) into the substrate below.

So many people believe their anchor model has good performance in weed because it will reliably hold full reverse from the engine and does not drag in 25-30 knots of wind. They will not necessarily realise that the anchor model is not capable of penetrating into the substrate below the weed. So the chance of the anchor holding in strong wind is not high.

When diving (and feeling what is happening), it is far more obvious which anchor designs are capable of using the setting force generated by the yachts engine to cut through the weeds and penetrate into the substrate below.

Originally Posted by groundtackle

Thin sharp toe.. nope. You couldn’t be more wrong.

You think a fat blunt toe is better?

Originally Posted by groundtackle

I don’t buy into the bigger argument.

Anchors normally scale well, but this does hold for weed. I sometimes see the enormous superyacht anchors that may be many 100’s of kilograms. Even if the design is poor, thick weed is just insignificant to this size and weight of anchor. At the other end of the scale, a small 10kg anchor often just cannot generate enough downward force to cut through a thick, heavy weed root even if the design is fundamentally sound. Big is better when it comes to weed performance. The only possible exception is light or medium weed over rock. A small anchor can sometime lock into a fissure in the rock which is too small for the bigger anchor. However, if the weed is thick the small anchor will never make it to the rock below so a heavier anchor is once again better, although the ideal is big heavy anchor with a very small fluke size such as fisherman or Marsh anchor. This is one reason why these models are so good in weed.

[noelex 77]

Originally Posted by GILow

The anchors themselves are so popular here in South Australia that they don't actually have to advertise them to sell them. They are easily on more than 50% of the boats around me.

Marsh anchors are certainly popular in South Australia. This was my comment from a visit to South Australia in 2014:

Originally Posted by noelex 77

A large percentage of boats had a specialist weed anchor. About 60% of boats had a Marsh stockless anchor (see photo) 10% a fisherman anchor. 20% were Rocna or Manson Supreme only a tiny number of CQR's, plows and Delta anchors (amazing) 0 Bruce anchors ( equally amazing) and only 1 Sarca anchor (surprising given their Australian manufacturing base) 0 Spade anchors ( not surprising given their poor distribution and high cost in Australia)

On my last visit to South Australia I did not do a formal count of numbers, but my distinct impression was the numbers of Marsh anchors are declining, but I do not visit often so this impression may be wrong. This may be because of supply difficulties, but I suspect this is due to the availability of new generation anchors that have much better weed performance than the older CQR and plow designs.

The Marsh is specialist weed anchor. It is ideally suited to weed and more particularly weed with an underlying hard substrate (especially rock). However, it is very limited in the substrates where it works well. When deploying an anchor you need to be sure of the type of substrate present.

If you are only cruising an isolated area where a suitable substrate is common, owning a specialist anchor such as this can make sense, but if cruising a larger geographic area I think a good (preferably oversized) general purpose anchor is a better choice.

Good weed performance I think deserves a lot of consideration when selecting a general purpose anchor. As there are almost no formal anchor tests conducted in weed there will always be great debate about the best weed performance from a general purpose anchor. My vote would be for the Mantus. Its thin, high aspect ratio chisel shaped tip without a bulky ballast chamber, really helps it cut through weed.

[GILow]

I think the single Sarca you saw back in 2014 was on my boat.

I’ll have another look around at the anchors with your observations in mind and see if I spot the same pattern.

You’ve made me curious.

And as you suggest, the Marsh comes off the bow once I leave South Australia later this year to be replaced with my much loved Sarca.

[DHHerndon]

I sail a Fisher 25 motorsailer, and I have found that my 17 lb Bulwagga anchor works very well in grassy bottoms.

[captprogreso]

Originally Posted by Cheechako

It has nothing to do with the Delta, as he said, his anchor is covered with mud and grass. The bottom does not hold the force of the boat. The Delta brought the bottom up with it, it didn't drag or come loose.
OP: it sounds like you need an anchor with more surface area, but a Danforth type is notoriously bad in grass so not sure what to recommend.
But more bottom info is needed.
-Grass and shallow mud over hard pan?
-Clay under shallow mud?
ie: do you need more surface area or need to penetrate better?

You are very right, the anchor after dragging was pulled out with a big chunk of mud and gras on top of it, i think the only way to improve the holding after reading all this post is to buy a bigger (read wider surface)anchor, and hope that the force needed to rip apart the mud and grass is high enought. No more good sleep in this part of yucatan peninsula. jajajaj

[Nicholson58]

121 # Rocna on our 40 ton, 58 foot ketch. In grass, we drop open clutch and pour out the full measure of chain for the scope. We do not set it but let the heavy tip gradually bed in. Backing down before it finds its way under the grass is a formula for dragging. If you can, send crew down to move it to a better spot.

[moodyfinn]

Well, it may seem a little out of the ordinary but I always dive on the anchor when in either a tight or grassy area as the point of my CQR does have trouble penetrating the grass roots. Also my wife will take the helm and apply a small amount of reverse and I observe from the water. If it does not take I request that the load is taken off and a very slow motor forward whilst I swim down pick up the anchor, sling it on my shoulder and wander around until I find a clearer patch. Drop it, jump on it, kick it and swim like hell to the surface. It’s really funny watching other cruisers wondering what on earth you are doing!

[Jimmyhenry]

Rocna 33kg. Bulletproof!!

[Seighlor]

Originally Posted by zeehag

love love love my oversized bruce. looking for a slightly smaller one, say 20 kg. mine is 30 kg...holds most excellently in all situations i have found so far.

I gave up on the Bruce after dragging multiple times in the Florida keys. The Bruce would consistently grab a wad of grass, complete with roots, and drag immediately while backing down. I went to my backup Danforth hi-tensile and had an immediate set.

I understand there are now better anchors than the old-school Danforth, but it's still a good anchor.

[GILow]

Originally Posted by Seighlor

I understand there are now better anchors than the old-school Danforth, but it's still a good anchor.

I have to agree. During my recent deck work I lost the use of my anchor winch for a few weeks. Retrieving the Marsh Stockless without a winch was simply out of the question. So I ended up anchoring with 20 meters of old jib sheet and my danforth kedging anchor. It was astoundingly good, including holding the boat for hours in 17 knots and building chop when I was unable to stop work on a half completed epoxy batch. That’s a 17 ton boat with a LOT of topside windage and cruising gear windage like davits and Bimini, solar etc. impressive little anchor that one.