Rocna Vulcan problems

[Mambo42]

That is some seriously good ground tackle, and as you say, definitely over specced for the size of boat. You must have a good anchor winch to get all that onboard again!
I’ve got the “baby” version of the Sarca Excel at a mere 36 kg’s , couldn’t be more pleased with its performance.

We use a Lofrans 24 V 1700 W anchor winch and that is connected to the house bank so won't run out of power.
It is a heavy anchor and a lot of chain, but we have lots of places in the Med where the weather can turn hair raising in a heartbeat. Especially when you are tied up to the shore you need to be sure your anchor is not going to drag.

 

[PierreR]

Have had both the Rocna and the Vulcan. Both great anchors but vastly prefer the Vulcan. As formal tests have shown the Vulcan has less trouble if current or tide shifts you 180 degrees. The Vulcan either stays below the bed surface or resets immediately. The Rocna doesn’t. Also in strong sustained loading I firmly believe the Vulcan buries deeper as it doesn’t have the resistance of the Rocna roll bar when it digs deep down. We were anchored in st. Anne’s outside LeMarin and it blowed dogs off their chains for a week. The Rocna held but you could still see the roll bar. After 2 days of similar conditions only chain showed with the Vulcan. I had to wake up and go through the whole move and reset rigamole with a reversing current with the Rocna more than once.

This is good information. I am right at the point of buying one or the other anchor. Size is still an issue for me. 25kg or 33kg. only 5/16 chain. Present 20 kg Bruce won't hold past 20-25 knots

 

[sunchaser]

Hundreds of Vulcan (40 kg , 55,000 lb boat) anchorages in all sorts of PNW conditions showed not one instance of dragging. But the shallow sandy with growth East Coast areas may yield a different outcome. We generally anchored the 3/8” all chain rode at 3:1 scope going to 5-6:1 in heavy winds. We did not like binding of high end swivel at times so stayed with an alloy shackel.

My thoughts on Vulcan center on be one’s roller and foredeck which will require some dutiful watching. We always retrieved from the bow to insure mud is removed and anchor shank is prepared for the final up an over. This is usually NOT a button push from the far away helm area so you’ll need bow controls as you watch the rode and anchor retrieve. The anchor could easily pull up 50 lbs of wet mud as it digs so hard. That weight makes the final up and over touchy due to weight imbalance so we always washed it off as it’s hanging there.

 

[Bmarler]

This is good information. I am right at the point of buying one or the other anchor. Size is still an issue for me. 25kg or 33kg. only 5/16 chain. Present 20 kg Bruce won't hold past 20-25 knots

For your size of boat I would think you’d have 30kg or bigger.

 

[PierreR]

For your size of boat I would think you’d have 30kg or bigger.

Chart says 33kg but 33kg is suppose to have 3/8" chain. My windlass appears to be strong enough and I use a snubber. 25kg looks okay, 5/16" chain but Rocna says for boats just a little smaller. I'm kinda in between. Not a high windage boat at about 20 ton.

 

[rslifkin]

I agree, definitely go for at least the 33kg for a Hatteras 42 LRC. I've got a 33kg Vulcan on my boat (38' LOD, 14' beam, 27.5k lbs loaded) and have been happy with it. Rocna recommended a 25kg model for my boat, but I went up a step as it would be the same effort to fit it on the bow. A 42 LRC is heavier than my boat and likely slightly higher windage as well.

As Sunchaser mentioned, in some bottoms it will bring up an impressive amount of muck. It also won't dock in the roller properly if it comes up completely backwards for any reason, but a nudge with a boat hook fixes that (once it's rotated a bit it'll spin into place as it hits the roller). Those with an all chain rode and no swivel likely won't have that problem, as it should always come up in the same orientation.

 

[Southern Boater]

We use a Lofrans 24 V 1700 W anchor winch and that is connected to the house bank so won't run out of power………

You certainly won’t with the energy your vessel produces, enough to power a small town

 

[Bmarler]

Chart says 33kg but 33kg is suppose to have 3/8" chain. My windlass appears to be strong enough and I use a snubber. 25kg looks okay, 5/16" chain but Rocna says for boats just a little smaller. I'm kinda in between. Not a high windage boat at about 20 ton.

I don’t think I’d worry about your chain being 5/16, I’d do the 33kg anyway.
I know the 3/8 gives better catenary, and that could be a factor, but probably not enough to matter. Maybe someone more knowledgeable in that area could shed more light.
I thought a 42 LRC had a fair amount of windage. I should look one up to refresh my memory.

 

[rslifkin]

I've got 5/16" G43 chain on my boat with the 33kg Vulcan. I'd consider it adequate for a 42LRC as well. Chain sizing is based on the expected load based on the boat, not based on the theoretical best case holding of the anchor.

 

[PierreR]

I've got 5/16" G43 chain on my boat with the 33kg Vulcan. I'd consider it adequate for a 42LRC as well. Chain sizing is based on the expected load based on the boat, not based on the theoretical best case holding of the anchor.

Well I will go to Rocna's site and download the full size pattern for the 33kg Vulcan and go to Staples or some place and have it printed out. Then I can cut of a wood pattern and try it in the roller for sizing on Wednesday.

 

[Nomad Willy]

mncruiser,
Re your #1 post it seems your problem is setting. I’ve said on TF for many years setting is the most important aspect of anchor performance.

An old school Danforth w forged shank and flukes is excellent. You’d need to find one used tho and most Danforth anchors used are the cheaper types using sheet metal/plate for flukes and shank. If you find one cheap or free that’s not bent try it. You’ll frequently find cheap used old anchors on CL. The cheaper Danforths may show you the capabilities generally of the Danforth in sand. If you have weed in your anchorages don’t bother w any Danforth.

Another excellent setting anchor is the Super Sarca. You can bolt off the slot but I’d recommend using it. I don’t know if you can do better for setting w any other anchor. This is my go to anchor when I don’t know what’s down there too.

For really good holding power and good setting the Fortress is super. It’s basically a Danforth design made of aluminum. If it dos’nt fit on your bow pulpit storing it flat on the fwd deck is a tried and proven solution. If you bend it straighten it and use it. But if bent quite a bit straighten it and buy a new one and keep the old straightened one as a spare.

A tip .. Basically a good sand anchor has a large fluke area. The Manson Boss may be a good one. Large fluke area for their weight. I spoke w a skipper in Sitka Ak. that has had lengthly experience w the Boss and has good reports.

 

[Hippocampus]

mncruiser,
Re your #1 post it seems your problem is setting. I’ve said on TF for many years setting is the most important aspect of anchor performance.

An old school Danforth w forged shank and flukes is excellent. You’d need to find one used tho and most Danforth anchors used are the cheaper types using sheet metal/plate for flukes and shank. If you find one cheap or free that’s not bent try it. You’ll frequently find cheap used old anchors on CL. The cheaper Danforths may show you the capabilities generally of the Danforth in sand. If you have weed in your anchorages don’t bother w any Danforth.

Another excellent setting anchor is the Super Sarca. You can bolt off the slot but I’d recommend using it. I don’t know if you can do better for setting w any other anchor. This is my go to anchor when I don’t know what’s down there too.

For really good holding power and good setting the Fortress is super. It’s basically a Danforth design made of aluminum. If it dos’nt fit on your bow pulpit storing it flat on the fwd deck is a tried and proven solution. If you bend it straighten it and use it. But if bent quite a bit straighten it and buy a new one and keep the old straightened one as a spare.

A tip .. Basically a good sand anchor has a large fluke area. The Manson Boss may be a good one. Large fluke area for their weight. I spoke w a skipper in Sitka Ak. that has had lengthly experience w the Boss and has good reports.

Currently using a fortress and a Vulcan. Other than very loose mud soup the fortress has stayed in the bag. Folded up it’s easy to store. Only problem is it’s better to assemble it and attach it before getting to the anchorage. We only have one roller so getting the Vulcan off is a PIA. When I get some boat bucks want to rework that set up to have two rollers, then will hang the fortress off the pulpit and will only have to connect it and drop it to anchor.

 

[Mac G]

And to add to what has already been said...
When determining scope it is water depth plus height of bow off water plus height until high tide!
So if you are only in Lake Superior, where there is no tide per se, then disregard.
But if ever in a tidal area that additional math is critical if you anchor at low tide and then experience a 10 foot increase (or more) later.
If windy I rarely use engines to back down but instead let the windage of the boat work on stretching the scope out.
Don't start dropping until you are dead stopped and starting to get blown backward.
Then pay out as boat drifts back on its own.
Once you think you are set, take bearings off fixed points on land and sit back and relax and check those later to confirm if you are firm.
And speaking of water depth and tide again, my understanding of the Great Lakes is while there might not be tide per se you can get wind driven water level fluctuations, right?
So if the forecast calls for a wind shift in the middle of the night that may push more water your direction then consider that additional scope too.

 

[PierreR]

I downloaded the the full size patterns for the Vulcan 33KG and Rocna 33kg and cut out wood patterns. Going to the boat tomorrow to try them.

 

[ronobrien]

I haven't followed the entire thread, but the comments on the Danforth design are right on. I had a Fortress storm anchor some years back (Wish I kept it when I sold the boat). The holding power of a Danforth design is great, especially in sand over that of a plow design.

 

[PierreR]

Vulcan it is, the Rocna MKii won't fit.

 

[jclays]

I have a 1997 Mainship 350. Same boat as yours. I use a genuine Bruce 44lb anchor. I have 100ft of 5/16 chain and 300ft of 5/8 three strand Nylon rode. The Bruce usually sets in one anchor length. I usually drop my anchor in reverse for a few seconds during the drop so that the anchor chain doesn't bunch. The slow reverse drift sets the anchor right away letting out the scope I am choosing and bring the boat to a gentle stop. I let is sit for about 10 minutes to let it settle in and set then I use reverse throttle to do the finial set starting at low and slowly increasing the throttle till I feel that the anchor is set. usually my wife has her foot on the road feeling for anchor bounce indicating that the anchor is dragging and not set. Really never a problem for a genuine Bruce of this size with our boat.

FYI the Bruce fits our bow roller perfectly and self launches.

 

[Delfin]

I have a 1997 Mainship 350. Same boat as yours. I use a genuine Bruce 44lb anchor. I have 100ft of 5/16 chain and 300ft of 5/8 three strand Nylon rode. The Bruce usually sets in one anchor length. I usually drop my anchor in reverse for a few seconds during the drop so that the anchor chain doesn't bunch. The slow reverse drift sets the anchor right away letting out the scope I am choosing and bring the boat to a gentle stop. I let is sit for about 10 minutes to let it settle in and set then I use reverse throttle to do the finial set starting at low and slowly increasing the throttle till I feel that the anchor is set. usually my wife has her foot on the road feeling for anchor bounce indicating that the anchor is dragging and not set. Really never a problem for a genuine Bruce of this size with our boat.

FYI the Bruce fits our bow roller perfectly and self launches.

We carried the same anchor on our 36' sailboat for 20 years. It dragged twice, once in Hospital Bay (mud) and once off Lahaina (sand). The problem with lighter weight Bruce anchors IMO is that they don't really keep digging into the seabed. They seem to reach a point of penetration, and after that, act like a plow if pulled on hard enough. That was certainly the case in Hawaii, as there was deep sand, and I could see the anchor just below the surface merrily scooting along as the boat dragged downwind.


A true 'diving' anchor, again IMO, like an Ultra, Excel or Danforth style will keep digging until the boat stops. I spoke with a Coast Guard cutter who had to cut their Fortress loose off the south end of San Juan Island because it had dug itself so far in even their powerful windlass couldn't raise it.

 

[sealandsky]

9 months after the fact... (In case you did not resolve the setting issue last summer) I was wondering if your Rocna isn't landing on the bottom inverted? Your anchor doesn't have a "roll bar" as some of that type do. You and I drop anchor in the same places and my 45 lb CQR bites hard on the bottom every time and with only a 3 to 1 scope. The water is usually clear enough that you might try getting a visual on the anchor after it lands on the bottom and before trying to set it.

 

[jclays]

I've found a Genuine Danforth that is stamped "Danforth Navy 1941" I has broader Flukes not the long tapered ones. These are more tear dropped or leaf shaped as it goes back from the point . Its a 30 pounder. Should be a nice backup anchor for my 39' Mainship 350. Have you seen these ones? They don't come up to often.

 

[Moonfish]

I've found a Genuine Danforth that is stamped "Danforth Navy 1941" I has broader Flukes not the long tapered ones. These are more tear dropped or leaf shaped as it goes back from the point . Its a 30 pounder. Should be a nice backup anchor for my 39' Mainship 350. Have you seen these ones? They don't come up to often.

A classic! Wonder just how many times that anchor has hit the sea floor in its lifetime...

 

[Snapdragon III]

It's always backing up too fast at the very beginning.

 

[mncruiser]

9 months after the fact... (In case you did not resolve the setting issue last summer) I was wondering if your Rocna isn't landing on the bottom inverted? Your anchor doesn't have a "roll bar" as some of that type do. You and I drop anchor in the same places and my 45 lb CQR bites hard on the bottom every time and with only a 3 to 1 scope. The water is usually clear enough that you might try getting a visual on the anchor after it lands on the bottom and before trying to set it.

Apologies for the late reply, the loss of the mobile app has made my visits here less frequent.

My problem was not enough scope. It was me, all along!

Previous to being back up on Lake Superior I boated on the Mississippi and St. Croix rivers. Smaller boat, shallower water...MUD, made anchoring easy and I thought I was good at it. Turns out I was not!

I think I have the right anchor for most of my anchoring. I was not putting out enough scope, I don't have a good system on the rode to track the emounbt I have out, fixing that this spring.

Thanks all for the discussion and replies.

 

[sealandsky]

One additional detail is how much chain you have. If just a short lead, you may want to consider a longer length of chain.

 

[Hippocampus]

One additional detail is how much chain you have. If just a short lead, you may want to consider a longer length of chain.

Important point. Chain not the anchor is what holds ships in place. Not as bad for boats but it’s still the chain that contributes a significant amount of holding even for boats. The chain should be resting on the sea floor for that effect. Yes a more horizontal vector helps with more scope but also more chain on the floor helps as well. Know from personal experience all chain dramatically increases holding. Especially in mud.

Ships will nearly always put out multiple “shackles “ (90’) of chain regardless of depth for that reason.

 

[rslifkin]

More chain does help holding, but it's been analyzed over on CF and determined that if you're adding more weight, it should be in the anchor. Pound for pound, up-sizing the anchor will add more holding power than more or heavier chain.

Chain weight becomes more useful by the time you get to ship size, as boats usually gain weight faster than windage as they get bigger. So for a ship, you can carry some extremely heavy chain where it will take a heck of a lot of wind to pull all of the useful catenary out of the chain. That's not the case for most recreational boats, particularly in shallower water where catenary is less effective.

 

[ronobrien]

I have heard of an anchor kedge being used, which amplifies the effect of the chain rode. I don't have much detail beyond what I had heard some time back.

 

[Hippocampus]

Both Rs above make good points. Have used a kellet on a friends boat who had chain and line. Seems easier to use with line as it slips down easier. He made the point it’s only effective if the kellet has significant weight. Otherwise you don’t get any real catenary effect. He would place it halfway to three quarters the way down the rode. He used discarded barbell's weights and would group them up until he saw catenary. I did this with him several times. He did it innumerable times so he knew in advance how much weight to use for different wind speeds. He had a big catboat so didn’t want weight in the bow from a lot of chain or big anchor but didn’t mind the stored weight of the barbell weights in the bilge while sailing.
Yes agree chain isn’t as nearly effective on boats as it is for ships. Thought I was clear about that. Still think it definitely helps. Especially in mud if it gets a chance to sink in.
Still a bigger anchor is much more effective than using a kellet. Seems everyone agrees on that. A kellet is only for specific curcumstances in my view. Forced to be on short scope or wanting the least weight possible in the bows.

 

[mncruiser]

One additional detail is how much chain you have. If just a short lead, you may want to consider a longer length of chain.

Thanks, I've pretty much got an all chain rode.

 

[Trawlerdream]

I have the same boat and Vulcan anchor. I have never had any problems setting the anchor. Use all chain and do not try to set until I have 4-5 scope out. When set I can reduce scope if needed.

Actually I think the Vulcan sets as good as the original Rocna I had on my sailboat.