Why Are Next-Gen Anchors Considered 'Better?'

[Therapy]

Originally Posted by Maine Sail

My only concern, and Alain/João have not answered it, is how does it perform on short scope with the shank attachment right at the very front of the anchor? Seems that on short scope it might just peel the tip right out with little resistance surface area in front of the shank.?

I have yet to see any independent testing of this anchor and would really like to see it and the web site still says under construction at this point.


Also keep in mind that this is about the third iteration of this design which started as the Oceane then became the Sword, or vice verse, and is now the Raya..

Sword: (image courtesy Sail World)


Oceane Anchor: (Photo courtesy blue water supplies)

Thanks for that.

Interesting, as always.

Just let me know when the Rocna is on sale! The 20kg I think is oversize for my Gemini but consensus is to use that size.

[sildene]

Maine Sail wrote:

Actually when you set with proper scope the weight of the chain does not really allow for "uprighting" of the anchor.

Actually, by change in "orientation" I did not expect the whole anchor to flip to an "upright" position, merely that the shank would lift off the ground to be parallel to the direction of rode pull; ie. the shank would end up parallel to the sea bottom as it is pulled by the rode, rather than continue to lie pointing downwards. Then, the anchor would remain on it's side, but the tip also won't be pointing downwards as much as it does in it's stationary position shown in the photo stills.

However, that is what I expect, not what I have seen. Your video trumps my 'mind experiment', and I take your point.

Maine Sail, thanks again for the time and effort you have taken to present the visuals - very informative.

Also, the point re. the cross-sectional differences between the anchors is well made and illustrated.

Martin

[mikereed100]

Originally Posted by Maine Sail

My only concern, and Alain/João have not answered it, is how does it perform on short scope with the shank attachment right at the very front of the anchor? Seems that on short scope it might just peel the tip right out with little resistance surface area in front of the shank.?

It's possible I'm visualizing this wrong but I think you may have this backwards. Draw a picture of an anchor with a short lever arm (shank) and another with a long lever arm, then draw a line from the end, representing a 3:1 rode. It looks to me as though the longer shank would tend to "lever" the tip out of the bottom, whereas the shorter shank provides more of a straight-line pull.

Mike

[mikereed100]

Here's a crude drawing illustrating what I mean. Notice that the rode is pulling up on the long shank anchor whereas it is still pulling down on the short shank.

[anathema]

Not a lot of anchor agents posting here any more. The son (I believe) of the Rocna inventor was posting on here for a while, but he was so rude and inflammatory that I believe he pushed quite a few over to the nearly identical (and less expensive) Manson supreme.

[imagine2frolic]

I followed the thread closely at SN. Maine Sail you always remain a gentleman when enquiring.. A.L. didn't fair so well at Multi forum either, for the same reasons?........i2f

[Therapy]

From a forum.

Indeed. We haven't anchored in any difficult bottoms or had a 180 windshift yet.

The lack of tip weight might be a disadvantage in weed. OTOH the Raya is very much sharper at the tip than the Spade and I would imagine that this might offset the lack of weight to a greater or lesser extent. João does say that they have a South American equivalent of kelp and that the Raya is designed to cope. We'll see, and you'll read all about it on here.
_________________

Waiting to see the follow-up.

P.S.

My offer still stands though summer is officially over.

[Boracay]

I remind participants in this thread of our Rules. Please reread them if you have any doubts as to how it should be conducted.

In particular please remember that this is a discussion between members. If you need detailed technical or business information then contact the manufacturer or dealer outside of this Forum.

Our normal advice to members who are unhappy with the posting of another member is to use the ignore button.

There is no right to receive a reply to any message or post.

If you feel that any message or post contravenes our Rules or the spirit of this Forum then use the warning button (bottom left hand of posting) to send a report to the Moderators.

[sildene]

A bit of topic drift up there, but in there somewhere it was noted that the geometry of the anchor (presumably shank versus fluke) can be chosen to ensure that it self-orients without the need for a roll bar.

It is not clear whether such a geometry has any negative effects or requires compromises - at least with the history of the Spade it does not seem to have had.

Every few years there seems to be a major boating magazine undertaking a comparative anchor test (the West Marine one was in 2006, I think), so you would hope that we're due for a fresh one soon. Let's hope when it comes, it includes the Raya and/or Sword, and that they include, in addition to the obligatory sandy bottom, a hard-to-penetrate bottom.

In fact, I sometimes think an anchor test could provide more useful information if done on land rather than under water. It would be nice to see a series of close-up photographs (or video) of how each anchor digs in, and eventually rips out as tension increases. And you would actually see how it happens that an anchor fails to penetrate a harder bottom. (Perhaps only a super-soft mud test may prove to be a bit tricky to stage on land).

Martin

[Pelagic]

Maine Sail… I really want to thank you for the fantastic work you have done on this thread to demonstrate the design tradeoff with anchors.

On my boat, this has been bothering me for quite a while as a solution to new generation anchors means some major bow work

Unfortunately on SG I have 2 x 75lb CQR’s and all chain which as you can see nestle under the bowsprit and swivel out of the way of the dolphin striker.

They have kept me out of trouble so far because I usually look for a depression somewhere on the chart and drop the anchor there, set carefully and continually monitor. But I agree with your assessment of them and sleep poorly when the weather comes up.

So, thanks to Maine Sail’s convincing explanation, I am going to bite the bullet and build a strong shoe forward of the bow spirit to somehow accommodate a roll bar type Manson or Rocna… unless you have any other suggestion that you think would work just as well but might look better. (PS… My priority is performance!)

Does anyone have any photos of a Rocna type installed on a long skinny bow spirit like mine, where the chain goes under the bow spirit then out to a shoe?

[GordMay]

I really dislike “captive” anchors, where the shank & rode come up through an anchor platform (on a sprit or not); much preferring an arrangement where the rollers are at the end or sides of the platform or bow (free & open), allowing the anchor and rode to be picked and moved, without disassembly.

I recognize the aesthetic challenge this poses to boats with anchor platforms.

Rocna tries to address some of the challenges in dealing with their anchors:
➥ Common fit challenges (Rocna Knowledge Base)
➥ Bow roller assembly design (Rocna Knowledge Base)
➥ Anchor retainment (Rocna Knowledge Base)

Rocna installation photos, by boat model:
➥ Category:Rocna bow compatibility (Rocna Knowledge Base)

(1) "captive", & (2) "free" anchors

[Pelagic]

Thanks Gord….. just what I was looking for. I have just emailed both Rocna and Manson for advice.


As you can see it is pretty busy on the bow spirit with the 2 anchor shanks behind the forward drum furler and my windlass quite far back.

I have been scratching my head about a good solution for this for quite some time...

This solution looks promising http://www.rocna.com/kb/Image:Selene...er-concept.pdf

[Solitude]

There seems to many more anchor discussions on this site than sail discussions.

[Therapy]

Originally Posted by Solitude

There seems to many more anchor discussions on this site than sail discussions.

That's cuz 90 percent of cruising is at anchor.

Or so I have read.

[colemj]

We are anchored in Weems Creek North of Annapolis right now in 20kts gusts to 30kts. Two boats with CQRs have spent the past 5 hours setting, dragging, resetting, etc. Luckily, there is no room upwind of us...