Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 28-03-2023, 15:16   #1
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Boat: Bestevaer.
Posts: 14,140
Rocna Mk II

Rocna are apparently about to release a new roll bar anchor that is a development of the original model. Details are very sketchy. It has only appeared in a stainless duplex prototype version so far.

Changes include:

An I beam shank similar to the Vulcan
A streamlined "foil" roll bar
More tip weight
The turned up rear portion of the fluke has been eliminated
Attached Thumbnails
Click image for larger version

Name:	967187FF-08F0-43BD-A8D2-909972DE5045.jpg
Views:	128
Size:	206.9 KB
ID:	273421  
noelex 77 is offline   Reply With Quote
Old 28-03-2023, 16:42   #2
Registered User

Join Date: Dec 2019
Location: Boston
Boat: Farr 50 Pilothouse
Posts: 1,295
Re: Rocna Mk II

Seems like someone over there has been watching Steve's tests.
Muaddib1116 is offline   Reply With Quote
Old 28-03-2023, 17:12   #3
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 5,186
Re: Rocna Mk II

Interesting that the rollbar is no longer round. It looks like they tried to keep it strong in the fore/aft direction without making it thick, likely in an attempt to reduce clogging. I'd bet that's why the up-turn in the fluke is gone as well. That shank definitely looks like a longer version of the Vulcan shank (which is quite beefy).

It looks like it has a little bit of ballast unlike other rollbar anchors. Interesting.
rslifkin is online now   Reply With Quote
Old 28-03-2023, 17:17   #4
Registered User

Join Date: Dec 2019
Location: Boston
Boat: Farr 50 Pilothouse
Posts: 1,295
Re: Rocna Mk II

Every change they made is a flaw or feature well documented by Steve on Panope. The rollbar and fluke tabs, and even the shank were easy mods, but increasing the tip weight without totally going down the road that Mantus and Viking did was probably only doable with some ballast.
Muaddib1116 is offline   Reply With Quote
Old 28-03-2023, 17:50   #5
Marine Service Provider

Join Date: Jan 2019
Boat: Beneteau 432, C&C Landfall 42, Roberts Offshore 38
Posts: 5,463
Re: Rocna Mk II

oh goody....another anchor thread...I'll go make some popcorn...
MicHughV is offline   Reply With Quote
Old 28-03-2023, 17:54   #6
Registered User

Join Date: Dec 2019
Location: Boston
Boat: Farr 50 Pilothouse
Posts: 1,295
Re: Rocna Mk II

Not sure there's much to argue about with this one yet. It does seem to be a pretty clear case of a company trying to improve their product based on user "feedback", which I certainly applaud.
Muaddib1116 is offline   Reply With Quote
Old 29-03-2023, 10:55   #7
Registered User
 
Karanga's Avatar

Join Date: Jun 2018
Location: NZ/Aus
Boat: Crowther 85 Catamaran
Posts: 269
Re: Rocna Mk II

It is looking a lot like a Vulcan, with a roll bar!
So if the roll bar contributes to risk of clogging, but doesn't do much to improve speed of setting (because of bigger ballast), why bother persisting with a roll bar (even with a modernised foil shape)?
Karanga is offline   Reply With Quote
Old 29-03-2023, 13:57   #8
Registered User

Join Date: Jun 2016
Location: Reston, VA, USA
Boat: Beneteau Oceanis 35.1
Posts: 373
Re: Rocna Mk II

I like my Vulcan.
Dr. D is offline   Reply With Quote
Old 29-03-2023, 14:44   #9
Registered User

Join Date: Dec 2019
Location: Boston
Boat: Farr 50 Pilothouse
Posts: 1,295
Re: Rocna Mk II

I think it's still much more of a Rocna than a Vulcan. The ballast they added is not nearly as large as the Vulcan or Spade design. The change in the shank is an upgrade, it presents a sharper leading edge, but it is still Rocna shaped. All the other changes are improvements based on evidence of common failure modes. The relatively small ballast bulb is probably to increase tip weight percentage without radically changing the overall fluke/shank shape/dimensions. In regards to the performance of rollbar anchors due to their flat fluke blades, this is some level of compromise. We probably won't know until people like Steve get their hands on one of these.
Muaddib1116 is offline   Reply With Quote
Old 05-04-2023, 08:58   #10
Registered User
 
Panope's Avatar

Join Date: Sep 2012
Location: Washington State
Boat: Colvin, Saugeen Witch (Aluminum), 34'
Posts: 2,179
Re: Rocna Mk II

I like that the "streamlining" of the rollbar is positioned/angled in such a way that when the anchor is on it's side or inverted and being dragged through soft mud, the rollbar will provide "lift".

Below is a screen grab of Rollbar Rocna (current version) that is perfectly stable while being dragged upside down through soft mud.

The assumption is that the rollbar (with round cross section) is buried into the substrate and is unable to right the anchor.

I am certainly not the first person to find that many anchor types have this problem in soft substrates (West Marine/Fortress Chesapeake Test).

I might be the first person to film it.
__________________
Panope's Modification/Refit: https://www.cruisersforum.com/forums...un-101572.html
Panope is offline   Reply With Quote
Old 13-04-2023, 13:47   #11
Marine Service Provider
 
Factor's Avatar

Join Date: Dec 2006
Location: Brisbane Australia
Boat: Multihulls - cats and Tris
Posts: 4,834
Re: Rocna Mk II

Quote:
Originally Posted by Karanga View Post
It is looking a lot like a Vulcan, with a roll bar!
So if the roll bar contributes to risk of clogging, but doesn't do much to improve speed of setting (because of bigger ballast), why bother persisting with a roll bar (even with a modernised foil shape)?
Who knows, Roll bar anchors are a furphy, but they are a very successful furphy. There is religious zeal amongst some for the idea.
Factor is offline   Reply With Quote
Old 13-04-2023, 17:49   #12
Registered User

Join Date: Nov 2018
Location: San Diego
Boat: Shannon 50 Ketch
Posts: 660
Re: Rocna Mk II

Quote:
Originally Posted by Factor View Post
Who knows, Roll bar anchors are a furphy, but they are a very successful furphy. There is religious zeal amongst some for the idea.
I had to look up "furphy" - "A rumour or story, especially one that is untrue or absurd." - a bold claim. And yet you say at the start "Who knows" so, "MAYBE a furphy"?

Meanwhile, I wish I knew if you are right, I am considering switching from a Vulcan to a (larger/heavier) RocnaII because I am of the belief that the rollbar is an improvement to the Vulcan, which (I thought) was a compromise for boats which can't fit a rollbar.
jordanbigel is offline   Reply With Quote
Old 13-04-2023, 18:16   #13
Registered User

Join Date: Jun 2019
Location: Rochester, NY
Boat: Chris Craft 381 Catalina
Posts: 5,186
Re: Rocna Mk II

Quote:
Originally Posted by jordanbigel View Post
I had to look up "furphy" - "A rumour or story, especially one that is untrue or absurd." - a bold claim. And yet you say at the start "Who knows" so, "MAYBE a furphy"?

Meanwhile, I wish I knew if you are right, I am considering switching from a Vulcan to a (larger/heavier) RocnaII because I am of the belief that the rollbar is an improvement to the Vulcan, which (I thought) was a compromise for boats which can't fit a rollbar.
Rocna initially treated the Vulcan as a compromise, but testing since then has shown otherwise. Rollbars can work well, but they also can run into some issues that non rollbar anchors don't.
rslifkin is online now   Reply With Quote
Old 13-04-2023, 20:01   #14
Registered User

Join Date: May 2008
Posts: 3,337
Re: Rocna Mk II

Most of the SV Panope anchor test top performers donít have roll bars.

Losing the roll bar isnít a compromise - itís an improvement
CarlF is offline   Reply With Quote
Old 13-04-2023, 21:48   #15
Registered User
 
Panope's Avatar

Join Date: Sep 2012
Location: Washington State
Boat: Colvin, Saugeen Witch (Aluminum), 34'
Posts: 2,179
Re: Rocna Mk II

Quote:
Originally Posted by CarlF View Post
Most of the SV Panope anchor test top performers donít have roll bars.

Losing the roll bar isnít a compromise - itís an improvement
Earlier in my testing, the best anchors tended to be the non-rollbar types.

However, after expanding the testing into a wider variety of seabed types, two rollbar anchors (Viking and Mantus M1) have emerged as the best "all around" performers.

Here is a story that might be telling:

I was readying my skiff for the task of towing a 30 foot sailboat for a distance of about 25 miles. With no information about the sailboat's anchor gear, I decided to grab, at the last minute, an anchor that could be used in an emergency to keep both boats off the rocks.

At my feet, on the floor of my shop, was my vast pile of anchors in the "20 pound" size range.

Without any prejudice, or other subjective motivations, I looked down and asked myself: "Which of these anchors as the greatest chance of producing a positive outcome?"

I grabbed a 21 pound Viking (an equal size Mantus M1 would have been just as good, but mine only weighs 17 pounds).

Note that I have bent Viking and Mantus M1 anchors during high pull tests.

If..... IF this new Rocna can perform as well as the Viking and M1 anchors, AND be as strong as the original Rocna, they just might have a game changer.
__________________
Panope's Modification/Refit: https://www.cruisersforum.com/forums...un-101572.html
Panope is offline   Reply With Quote
Reply

Tags
rocna

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Want To Buy: Rocna 25 (or trade for Rocna 20) Foggie303 General Classifieds (no boats) 0 24-01-2020 12:20
Will be trying out a Rocna anchor rsn48 Anchoring & Mooring 162 04-04-2009 00:14
Rocna-Vancouver allsail68 Anchoring & Mooring 5 13-09-2007 08:56
Suggestion for American Distribution of Rocna rsn48 Anchoring & Mooring 11 18-04-2007 21:07

Advertise Here


All times are GMT -7. The time now is 19:51.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2023, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2023, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.