25kg rockna or 20kg vulcan?

[Cdicko]

simply.............. 12 meter boat............. 25kg rockna or 20kg vulcan? )......... im not interested in views of size mainly design?? Advice?

 

[Neeves]

simply.............. 12 meter boat............. 25kg rockna or 20kg vulcan? )......... im not interested in views of size mainly design?? Advice?

Do they both fit on your bow roller? Furling gear can be located close to deck making roll bars a bit of a nuisance and sometimes the windlass is too close to the roller to allow the shank to be pulled far enough aft to house the fluke.

You seem to have already decided that Knox (locally made, I think UK steel), Viking (support Ukraine industry, Swedish steel), Epsilon (UK company, made in China), Spade (French, made in Tunisia) or Excel (Australian, made in Australia from Australian steel) are not for you - It would be interesting to know why they have each been rejected. I suspect you local chandler stocks both Rocna and Vulcan - not a reason buy either.

My conclusion on the motivation and inspiration for both Rocna and Vulcan - Peter Smith admired the Spade design and Rocna is a copy of Spade but with much cheaper and simpler manufacture. Later when patents became less of an issue he redesigned Rocna (bearing in mind his inspiration) and came up with Vulcan. In the interim Ultra also appear inspired by Spade and Epsilon (the most recent introduction) has not ignored Spade either (and may marry Spade, with the influence of the enduring success of convex (CQR, Delta, Kobra, Excel).

Spade, particularly, and Rocna are now quite old designs and design has moved forward. I think you would be happy with any of the anchors I mention (they will not let you down, and will all be easy and reliable to set,) but I would favour some of the newer designs which remove some of the niggles that detract from both Spade and Rocna. None of these designs, that I mention, will give you stellar performance in soupy mud (use a Fortress) - and you omit to mention your common seabeds. If you do anchor in mud - Rocna will allow you to sample the seabed every time your retrieve - and for this reason alone I would discount it. Most anchors will collect mud - Rocna is particularly bad - you would need a powerful deck wash. If weight might be an issue - I'd look at Viking, the Viking 15. If you consider a Viking you can add a Boomerang (to replace your swivel) and chain hook (for your snubber) to your purchase and save on freight costs (maybe you can persuade them to throw both items in as a sweetener - if you don't ask you will never know )..

I mention snubber as I don't think one buys an anchor in insolation - the ground tackle is a complete package which should be made up of compatible components.

When you get closer to deciding - take a couple of links of your chain to the anchor you intend to buy and ensure that you can source a sensible shackle that will be strong enough and fit both anchor slot and chain link. Unfortunately the best shackles remain those from Crosby and you may have to source mail order - but all, say 1/2" shackles, are the same size and if you find a 1/2" fits in the local chandler - then you can buy a 1/2" Crosby relatively easily. (I buy from Tecni in the UK - impossible to source cheaply in Oz). ). If you have a local lifting gear supplier - Crosby bought Gunnebo (big in aquaculture) and Gunnebo are active across all of Europe - and if your local lifting gear supplied Gunnebo than they may hold Crosby shackles.

I'm not answering your question, apologies - but maybe offering you some alternative thoughts.

You will not go wrong with your restricted list and my slightly more 'modern' ideas.

Jonathan

 

[Cdicko]

Do they both fit on your bow roller? Furling gear can be located close to deck making roll bars a bit of a nuisance and sometimes the windlass is too close to the roller to allow the shank to be pulled far enough aft to house the fluke.

You seem to have already decided that Knox (locally made, I think UK steel), Viking (support Ukraine industry, Swedish steel), Epsilon (UK company, made in China), Spade (French, made in Tunisia) or Excel (Australian, made in Australia from Australian steel) are not for you - It would be interesting to know why they have each been rejected. I suspect you local chandler stocks both Rocna and Vulcan - not a reason buy either.

My conclusion on the motivation and inspiration for both Rocna and Vulcan - Peter Smith admired the Spade design and Rocna is a copy of Spade but with much cheaper and simpler manufacture. Later when patents became less of an issue he redesigned Rocna (bearing in mind his inspiration) and came up with Vulcan. In the interim Ultra also appear inspired by Spade and Epsilon (the most recent introduction) has not ignored Spade either (and may marry Spade, with the influence of the enduring success of convex (CQR, Delta, Kobra, Excel).

Spade, particularly, and Rocna are now quite old designs and design has moved forward. I think you would be happy with any of the anchors I mention (they will not let you down, and will all be easy and reliable to set,) but I would favour some of the newer designs which remove some of the niggles that detract from both Spade and Rocna. None of these designs, that I mention, will give you stellar performance in soupy mud (use a Fortress) - and you omit to mention your common seabeds. If you do anchor in mud - Rocna will allow you to sample the seabed every time your retrieve - and for this reason alone I would discount it. Most anchors will collect mud - Rocna is particularly bad - you would need a powerful deck wash. If weight might be an issue - I'd look at Viking, the Viking 15. If you consider a Viking you can add a Boomerang (to replace your swivel) and chain hook (for your snubber) to your purchase and save on freight costs (maybe you can persuade them to throw both items in as a sweetener - if you don't ask you will never know )..

I mention snubber as I don't think one buys an anchor in insolation - the ground tackle is a complete package which should be made up of compatible components.

When you get closer to deciding - take a couple of links of your chain to the anchor you intend to buy and ensure that you can source a sensible shackle that will be strong enough and fit both anchor slot and chain link. Unfortunately the best shackles remain those from Crosby and you may have to source mail order - but all, say 1/2" shackles, are the same size and if you find a 1/2" fits in the local chandler - then you can buy a 1/2" Crosby relatively easily. (I buy from Tecni in the UK - impossible to source cheaply in Oz). ). If you have a local lifting gear supplier - Crosby bought Gunnebo (big in aquaculture) and Gunnebo are active across all of Europe - and if your local lifting gear supplied Gunnebo than they may hold Crosby shackles.

I'm not answering your question, apologies - but maybe offering you some alternative thoughts.

You will not go wrong with your restricted list and my slightly more 'modern' ideas.

Jonathan

cheers Jonathan Thank you for your very comprehensive reply. Maybe I should change the thread to Viking or vulcan? (yes viking is up there on my list too, I already have the mud collecting Rocna hence its existence in the question). watching SV Panope and as a rule he doesnt fit a swivel, what's your thoughts not fitting a swivel? Chris

 

[Sandy]

How about a Knox? Made in Scotland.

 

[Cdicko]

How about a Knox? Made in Scotland.

Only just heard of Knox today. just looked on the Knox website. Have you got one? does it preform well?

 

[Sandy]

I do have one. Its never let me down. I have a 10.10 metre boat (33ft in old money) and went for the 13kg one as I was just on the cusp between that and the lighter 6.5kg one.

I liked the ability to be able to call the manufacturer up if ever there was a problem with it. You don't get to do that with many bits of kit.

 

[sailoppopotamus]

We haven't had an anchor thread for a few days, this will be exciting. I do not profess to be an expert on the matter, but these are my thoughts:

I just got myself a 12kg Vulcan, to replace a 10kg Delta knockoff, even though my bow roller would accommodate a Rocna 10kg just as well. I bought the Vulcan over the Rocna on the (perhaps unfounded) basis that I don't want a rollbar that might potentially clog with crap, and SV Panope's tests that show the Rocna not doing very well in a number of sea beds. Are these tests trustworthy? I don't know. I was very tempted by the Viking, but it's very long and wouldn't fit my bow roller without serious modifications.

I have yet to use the anchor, It looks like I will need some minor modifications on the bow roller anyway, to get it to stay firmly in place when sailing. My confidence in my choice has been somewhat dented by SV Panope's recent tests in soupy mud. But the anchor has been bought, and it's unlikely to be worse than the smaller Delta copy it replaced. I'll evaluate it over the coming season and see where I stand.

To get back to the topic: 25KG Rocna vs 20kg Vulcan: Why not 25KG Vulcan, why are we comparing anchors of different sizes? What's the recommended anchor size for the boat, according to Rocna?

 

[Neeves]

We haven't had an anchor thread for a few days, this will be exciting. I do not profess to be an expert on the matter, but these are my thoughts:

I just got myself a 12kg Vulcan, to replace a 10kg Delta knockoff, even though my bow roller would accommodate a Rocna 10kg just as well. I bought the Vulcan over the Rocna on the (perhaps unfounded) basis that I don't want a rollbar that might potentially clog with crap, and SV Panope's tests that show the Rocna not doing very well in a number of sea beds. Are these tests trustworthy? I don't know. I was very tempted by the Viking, but it's very long and wouldn't fit my bow roller without serious modifications.

I have yet to use the anchor, It looks like I will need some minor modifications on the bow roller anyway, to get it to stay firmly in place when sailing. My confidence in my choice has been somewhat dented by SV Panope's recent tests in soupy mud. But the anchor has been bought, and it's unlikely to be worse than the smaller Delta copy it replaced. I'll evaluate it over the coming season and see where I stand.

To get back to the topic: 25KG Rocna vs 20kg Vulcan: Why not 25KG Vulcan, why are we comparing anchors of different sizes? What's the recommended anchor size for the boat, according to Rocna?

I'll try to make this as exciting as possible - to reward your investment in time on the poorly documented discussions on anchor choice.

If you have doubts, which you actually express, on the veracity of results by Steve Godwin (aka Panope) on Rocna then I'd question why you don't express concern on the reality of his work on other anchors - unless you think he has a vendetta against Rocna.

However mud is difficult to define but Fortress conducted tests recently in soupy mud - and no anchor was reliable in soupy mud - except Fortress (what would you expect - but they were sponsoring the work and they only tested in soupy mud). I thought the results had validity and in mud - we use a Fortress, as the limited work I have done in mud supports the results they achieved. I would not therefore damn an anchor for failing soupy mud - other anchors are no better (including our Excel and Spade - the Viking is the best in my collection - but not a match to the Fortress..

cheers Jonathan Thank you for your very comprehensive reply. Maybe I should change the thread to Viking or vulcan? (yes viking is up there on my list too, I already have the mud collecting Rocna hence its existence in the question). watching SV Panope and as a rule he doesnt fit a swivel, what's your thoughts not fitting a swivel? Chris

You actually know if you need a swivel

We don't use a swivel (hardly a surprise) we use a Boomerang.

This is our Boomerang, paired with an aluminium Excel and our 6mm high tensile chain. We have beached and are waiting for the tide to retreat to clean the props.


Note that the Boomerang is sitting 'vertically' and some of the rode is buried. If the anchor had been tensioned higher the chain and Boomerang would be more deeply buried and along with the shank would resist veering. Most modern anchors, Rocna, Spade, Knox, bury chain in a similar way - and bury the chain at roughly the same rate as the fluke is buried. Under more tension the anchor would become more symmetrical, it still has a bit of a list.


If you (or your crew) retrieve at the bow, can see the orientation of the anchor as it approaches the bow roller and they (or you) are happy to correct any misalignment, by hand or a stick - you don't need a Boomerang. Actually if you have a swivel and the anchor arrives misaligned the swivel does not 'do' anything - you have to correct the misalignment. The swivel is simply too crude a device and friction will simply be too much - they don't
actually swivel 'automatically' you need to do the swivelling.

The design of anchors, the fact they are generally self launching results in their automatically self righting them selves. If they arrive at the bow roller 'upside down' then they should self righting, if they have time (the windlass can be too quick) or the bow roller is wide enough to allow them to rotate. But having a 25kg chunk of steel rotating through 180 degrees on you bow is really not ideal - as you have some expensive kit up there and if you would not hit it with a sledge hammer why allow the anchor to belt it one !.



Simply put a Boomerang will self right the anchor, every time and before the anchor actually reaches the bow roller. But they are not for everyone. If your windlass is too close to the bow there may not be room for a Boomerang and they don't work if they 'fit' into the slot on a slotted bow roller. You can make your own, my original article was focussed at this simple task, or you can buy one from Viking and maybe Jimmy Green (Anchor Right in Australia copied my design - and JG sell their anchors). You could also try Knox Anchor as I recall they made at least one.

If you want to make your own the downsides are - you need to either make from stainless or have it galvanised, you need a decent angle grinder and a bench drill and ideally I'd make from a 'higher' tensile steel (to ensure it is stronger than your chain). If you want to make your own - send me a PM and I'll send a link to the original article.

If you retrieve short handed, your crew is not confident, you retrieve from the cockpit - then a Boomerang is for you.

I believe delivery from Ukraine for Viking's Boomerang is expensive (in comparison to their cost) and I'm guessing is most effective to buy a Boomerang if you buy one of their anchors.

I don't make any money - I'm happy and pleased if people find them useful (and my bridle plate ).

Its part of my philosophy - knowledge is of no value - unless it is shared

Jonathan

 

[RunAgroundHard]

Knox experience.
Knox, 18kg, boat 41”, 22klbs displacement. It replaced a 60lb CQR. Works well, fast setting, has held in 45kt gusts, mud seabed. I have used it on sand seabeds and in Kelp with good holding based on reversing in. It does have a very strong shank and is a quality build, good galvanising. Will lift up dobs of mud but they fall off with dunking or just motoring ahead with the anchor just below surface, my bow shape allows this. Happy with my choice, better holding, lighter to handle on surface thank CQR.

Worth considering in my view. Feel free to ignore, no need to comment if you have decided on the one of the two stated in your OP.

Rocna was a choice but at the time there was bad press about the shank strength. Today their shanks still look puny compared to the Knox.

 

[vyv_cox]

It has been brought to my attention that the larger Rocna in the SV Panope tests (25 kg?) was given to him with a bent shank. He tried to straighten it, by his own admission unsuccessfully. Not unexpectedly it did not perform well. The smaller one apparently performed well, as it was in good condition.

 

[Neeves]

Knox experience.
Knox, 18kg, boat 41”, 22klbs displacement. It replaced a 60lb CQR. Works well, fast setting, has held in 45kt gusts, mud seabed. I have used it on sand seabeds and in Kelp with good holding based on reversing in. It does have a very strong shank and is a quality build, good galvanising. Will lift up dobs of mud but they fall off with dunking or just motoring ahead with the anchor just below surface, my bow shape allows this. Happy with my choice, better holding, lighter to handle on surface thank CQR.

Worth considering in my view. Feel free to ignore, no need to comment if you have decided on the one of the two stated in your OP.

Rocna was a choice but at the time there was bad press about the shank strength. Today their shanks still look puny compared to the Knox.

The quality of the Knox build looks exceptionally good and robust. The welds are massive. There is a possibility it is over engineered (not a characteristic that should be ignored). People complain that Danforth and Fortress catch items in the toe between the 2 split flukes. An individual whose integrity I respect tested a Knox and had his chain caught in the split toe - suggestions were made that the toe might be closed - but this has not eventuated. I have tested a Knox and find it a good anchor and have not had our chain caught in the toe - but it is quite possible. You could seal the gap with an inter screw

Rocna did have a period when the steel used in the shanks was below specification - and shanks bent. The issue was resolved - though it was never declared what the quality was of the 'remedial' (replacement) steel - except that it was adequate. Prior to the lapse in quality control and after the problem was identified and shank steel quality returned to 'adequate' I have never heard of a shank bending - and there are a lot of Rocna anchors out there.

I am not a fan of Rocna, someone let their eye off the ball - which I find difficult to forgive (but that's me, but I try to be objective - all anchors are a compromise - its a good anchor). But the issue was resolved and I intensely dislike the trolling that is still evident even though the anchors were replaced free of charge, the error identified and rectified and there have been no issues since.

What possessed the testing in the first place of an anchor with a bent shank - needs questioning.

Jonathan

 

[sailoppopotamus]

I'll try to make this as exciting as possible - to reward your investment in time on the poorly documented discussions on anchor choice.

If you have doubts, which you actually express, on the veracity of results by Steve Godwin (aka Panope) on Rocna then I'd question why you don't express concern on the reality of his work on other anchors - unless you think he has a vendetta against Rocna.

I didn't want to attack Steve, apologies if it came across that way. Quite the contrary, I find his videos very interesting and took them very much into account when deciding which anchor to buy. On the other hand, I appreciate that his tests are only one source of information and not gospel. I trust them enough to inform my own buying choice, but not enough to go on a public forum and openly denigrate an anchor as popular as the Rocna.

 

[vyv_cox]

The quality of the Knox build looks exceptionally good and robust. The welds are massive. There is a possibility it is over engineered (not a characteristic that should be ignored). People complain that Danforth and Fortress catch items in the toe between the 2 split flukes. An individual whose integrity I respect tested a Knox and had his chain caught in the split toe - suggestions were made that the toe might be closed - but this has not eventuated. I have tested a Knox and find it a good anchor and have not had our chain caught in the toe - but it is quite possible. You could seal the gap with an inter screw

Rocna did have a period when the steel used in the shanks was below specification - and shanks bent. The issue was resolved - though it was never declared what the quality was of the 'remedial' (replacement) steel - except that it was adequate. Prior to the lapse in quality control and after the problem was identified and shank steel quality returned to 'adequate' I have never heard of a shank bending - and there are a lot of Rocna anchors out there.

I am not a fan of Rocna, someone let their eye off the ball - which I find difficult to forgive (but that's me, but I try to be objective - all anchors are a compromise - its a good anchor). But the issue was resolved and I intensely dislike the trolling that is still evident even though the anchors were replaced free of charge, the error identified and rectified and there have been no issues since.

What possessed the testing in the first place of an anchor with a bent shank - needs questioning.

Jonathan

I destructively tested one of the new Rocna shanks. Its strength was not quite up to Bisalloy standard but only a little less. Getting on for twice that of a Delta, same thickness per weight, and they are not often bent.