An unlucky Vulcan

[ThereAndBack]

So... my confidence in my "sorta new" Rocna Vulcan 33 anchor is shaken.

I replaced a Rocna 40kg (88lbs) anchor late last year after it was irretrievably fouled. I replaced it with a Rocna Vulcan 33kg (73lbs) as this was the only suitably sized anchor available to me where I was at the time. I had considered trying this anchor anyway so it seemed good fate that the one I wanted to try was the one available. Anyway...

Down the ICW from Charleston to Key Biscayne I had no problems at all with it and I was pleased with the anchor. It was still the "getting to know you" phase but things were going well.

After I crossed Mackie shoal in the Bahamas I decided to anchor out in 15ft of water and dropped the anchor in clear white sand but did not back down, it seemed to have set. A squall blew in that night (25ish kts) and we were just dragging constantly at about a .2-.3kts and the anchor was not (re)setting. I was a little put off by this but chalked it up to pour technique on my part by not properly setting in the first place. That said, I'm convinced my previous anchor would have plowed in once we started to move that much.

Next I anchored at Bird Cay for a while and it was light grass with sand over coral/rock. Not the greatest conditions. While the anchor did "ok", it never buried itself at all. Once again, I forgave it. I said, "this is tough for any anchor".

Next I anchored at Allen Cay in clear white deep sand. IDEAL anchoring bottom. I dropped and the hook almost immediately went deep, buried up to the shank. And I thought, now, I can see this anchor in real action. Well... Last night the winds got up above 20kts and the tide shifted a few times and we drug some 100ft before we stopped. It did hold after the dragging.

This morning I re-anchored to get into a better spot and when I lifted the anchor there was a big ball of twine or small line around it that I had to get off with a gaff.

Now each time the anchor has failed my expectations, there has been some circumstance I can lay blame to that isn't the anchor itself. However, I've NEVER had this many back to back bad experiences with any of my previous anchors. ( Previous anchors both same sort, classic roll bar Rocna and Manson Supreme). This is the first time I've used an anchor like the Vulcan (similar to a Spade).

Am I doing something wrong? Does anyone have a lot of faith in their Vulcan? Is this just bad luck?

I'm considering going straight to a Mantus when I get back stateside but I wanted a sanity check with the communal mind here first. Thanks for your feedback.


Appendix:
43 ft Catamaran, 12.5T, low windage for a cat
All chain - 8mm HT, 15 foot oversized bridle
Normal procedure is to drop anchor until bottom, deploy some small amount of chain, begin backing down gently while paying out chain then stop paying chain and feel the boat "hook". Once it has hooked we again go into reverse and pay out. Once 5:1 scope (or better) is reached, we snub the anchor. Once snubbed I usually back down fairly hard for around 60-120 seconds while taking sights or watching GPS to detect drag. Fairly hard for us means 80% power. I have two 29hp motors. It isn't a lot of force compared to boats with big motors but it is enough to pull the bridle all the way up out of the water and hold it there when we back down.

[boatman61]

To my mind your not using enough chain.. you have a 43ft boat yet only lay out 50ft of chain.
I operate on the principle of 3 x boat length of chain so if my boat is 30ft I lay out 90ft of chain plus depth in 5 metres depth and sit in my cockpit watching the short rodes drag past me when the wind picks up.
I know I'm set for flak and being called selfish but.. you wanna risk your boat on a short rode in an over crowded anchorage that's your call but don't expect me to.

[ThereAndBack]

Originally Posted by boatman61

To my mind your not using enough chain.. you have a 43ft boat yet only lay out 50ft of chain.
I operate on the principle of 3 x boat length of chain so if my boat is 30ft I lay out 90ft of chain plus depth in 5 metres depth and sit in my cockpit watching the short rodes drag past me when the wind picks up.
I know I'm set for flak and being called selfish but.. you wanna risk your boat on a short rode in an over crowded anchorage that's your call but don't expect me to.

Thank you for the feedback and indeed, I may want to experiment with adding more scope for this type of anchor, but I'm curious where you got the "only lay out 50ft of chain"?

Generally speaking I put out a 5 to 1 scope as measured by:
Depth x 5 + tide + 3ft (which is the height of the attachment points for bridle above the waterline).

In rougher weather I usually deploy 7 to 1 or more if it isn't crowded.

If I'm reading what you're saying, you drop the depth + 3 times boat length? For me that would mean paying out 40m of chain when anchoring in 2m depths?

[Chotu]

I also don’t like the deployment technique.

You said you had a big ball of string or small line knotted around the anchor the last time? Well, the way you drop it sounds like you drag it across the bottom quite a bit before you set it. That could be what caused that problem at least.

If you are dropping it somewhere, then you are backing down while you are slowly increasing the scope, it’s going to drag and move across the bottom and even “fly” underwater as you are doing that. Before it can get a bite. Because the scope is too short still and you’re moving.

Maybe you should try just dropping it, moving back just a couple feet, putting it in neutral, and then dumping out as much chain as you think you need, and then either drifting or slowly motoring the boat back until it can set. And it will set HARD doing this and at the right angle.

If you picture this in your mind’s eye, you can see that when you have the full scope out during the set, the anchor will set into the sea bed at a better angle than it would if you are doing it the way you do typically. And it would set immediately rather than dragging along for a bit until the scope gets long enough for it to actually set properly.

As an added bonus, you won’t be dragging it along picking up whatever crud there is along the sea bed.

Note: before building the boat, I had spent more nights living at anchor than I have on land in my lifetime. I have never dragged before. Ever. Even with bad old CQR anchors from back in the day. I’m 10:1 scope at low tide. In places like Maine, I am 10 to one at half tide. I don’t care what anyone in the Anchorage thinks about that. They should be on longer scope also. Then again, I don’t really go into the super crowded anchorages because they are not my style. Or if I do, I look for a big open spot and take it.

[ThereAndBack]

Originally Posted by Chotu

I also don’t like the deployment technique.

You said you had a big ball of string or small line knotted around the anchor the last time? Well, the way you drop it sounds like you drag it across the bottom quite a bit before you set it. That could be what caused that problem at least.

If you are dropping it somewhere, then you are backing down while you are slowly increasing the scope, it’s going to drag and move across the bottom and even “fly” underwater as you are doing that. Before it can get a bite. Because the scope is too short still and you’re moving.

Maybe you should try just dropping it, moving back just a couple feet, putting it in neutral, and then dumping out as much chain as you think you need, and then either drifting or slowly motoring the boat back until it can set. And it will set HARD doing this and at the right angle.

If you picture this in your mind’s eye, you can see that when you have the full scope out during the set, the anchor will set into the sea bed at a better angle than it would if you are doing it the way you do typically. And it would set immediately rather than dragging along for a bit until the scope gets long enough for it to actually set properly.

As an added bonus, you won’t be dragging it along picking up whatever crud there is along the sea bed.

An interesting point. I guess I never thought of this as the previous anchors would let me know immediately even short scoped if they'd hooked up and I sort of depend on that. I can try paying out full scope before trying to set and see how that goes.

As far as the ball of string incident, I don't think it was related to the setting technique. As when I dropped the hook in this anchorage I didn't have time to stop paying out or back up at all before the anchor immediately buried itself in the sand. I could see this due to the water clarity in this anchorage. It hit the bottom and immediately plowed in.

[ThereAndBack]

Originally Posted by Chotu

Note: before building the boat, I had spent more nights living at anchor than I have on land in my lifetime. I have never dragged before. Ever. Even with bad old CQR anchors from back in the day. I’m 10:1 scope at low tide. In places like Maine, I am 10 to one at half tide. I don’t care what anyone in the Anchorage thinks about that. They should be on longer scope also. Then again, I don’t really go into the super crowded anchorages because they are not my style. Or if I do, I look for a big open spot and take it.

For reference, I'm not as experienced as it sounds that you are, however, I'm also not "new" to the game. I've cruised for 7 years total and I'm very rare to stay at a dock. With the exception of one year parked during the covid times. I estimate my total nights at anchor somewhere north of 1000+ nights. I've also anchored up and down the east coast US, gulf coast US, and the entire Caribe in all weathers in multiple types of boats.

This is the first time I've had "trouble" anchoring repeatedly.

[boatman61]

Scope is a term I only came across when I joined CF and from my understanding it works in 10's so 7:1 = 70ft.
Now I would only anchor in 2m at lw in very sheltered spots as an onshore wind would likely have me bottoming if there was wave action at an open anchorage like a bay.
But then unlike many I don't like getting as close as possible to the beach or dinghy Dock for convienience.

QUOTE from Anchor Caddie..
The general rule I always hear is what is called a scope of 7:1, which means if you are in 1 foot of water, you would use 7 foot of anchor line, 10 foot of water = 70 foot of anchor line, etc.

Now this 7:1 scope is meant to cover everything up to extreme conditions where you are anchored in overnight or extreme conditions, such as major current, tide or weather conditions.

[Chotu]

Originally Posted by ThereAndBack

For reference, I'm not as experienced as it sounds that you are, however, I'm also not "new" to the game. I've cruised for 7 years total and I'm very rare to stay at a dock. With the exception of one year parked during the covid times. I estimate my total nights at anchor somewhere north of 1000+ nights. I've also anchored up and down the east coast US, gulf coast US, and the entire Caribe in all weathers in multiple types of boats.

This is the first time I've had "trouble" anchoring repeatedly.

Sorry. That wasn’t about you. May be a little out of context.

That was a preemptive strike on the haters. Ha ha.

No, seriously I said that so that you would know that my technique has worked for thousands of times at anchor. And in my opinion, setting it on the long scope is really important because the angle of the dig is correct in that case. Also just using more scope is important in my opinion as well. That’s the only reason I was stating how much time I have spent not dragging at anchor. Just so that it puts it into some context.

Because anyone can come on here and have some theories. But I wanted to show that over decades of living at anchor, these techniques have worked for me. Even with old “state of the art” CQRs.

So that wasn’t really aimed at questioning your experience. Apologies if it sounded like that.

When you put it that way though, who knows? Maybe that anchor isn’t doing very well for you. I certainly wouldn’t feel confident in it either based on your long history of anchoring and your stories of the fails. I really loved my Manson supreme. But my Rocna is now doing about the same. It’s the rollbar Rocna. I haven’t really noticed a difference between them yet.

I don’t think I’ll ever change from these anchors. They have been doing me really well.

[ThereAndBack]

Correct, the scope being defined as (Depth X Scope). So 5ft depth at 5:1 scope would mean paying out 25ft of rode if the rode was attached at the waterline and you were already at high tide.

Generally I abide by:
Normal conditions: 5:1 scope
Breezy/stormy/tidal shifts: 7:1 scope
Storm: 10:1 scope
Tropical storm: Everything you've got.

[ThereAndBack]

Originally Posted by Chotu

Sorry. That wasn’t about you. May be a little out of context.

That was a preemptive strike on the haters. Ha ha.

No, seriously I said that so that you would know that my technique has worked for thousands of times at anchor. And in my opinion, setting it on the long scope is really important because the angle of the dig is correct in that case. Also just using more scope is important in my opinion as well. That’s the only reason I was stating how much time I have spent not dragging at anchor. Just so that it puts it into some context.

Because anyone can come on here and have some theories. But I wanted to show that over decades of living at anchor, these techniques have worked for me. Even with old “state of the art” CQRs.

So that wasn’t really aimed at questioning your experience. Apologies if it sounded like that.

When you put it that way though, who knows? Maybe that anchor isn’t doing very well for you. I certainly wouldn’t feel confident in it either based on your long history of anchoring and your stories of the fails. I really loved my Manson supreme. But my Rocna is now doing about the same. It’s the rollbar Rocna. I haven’t really noticed a difference between them yet.

I don’t think I’ll ever change from these anchors. They have been doing me really well.

I didn't take it that way. I considered it as context setting and so I in turn also gave context. I'm sure this would be a very different discussion if I was someone that had never spent a night on the hook, etc.

[carstenb]

We have a motto on our boat:

In Mantus we trust.

After close to 2000 nights at anchor over most of the world, we have dragged exactly once (1).

There is was our own fault

I also might question your technique. We generally leave the engine in idle reverse when we drop the hook - just enough to keep the chain from bunching up on the seabed. When we feel the chain tighten up, we back down until we are at 2500 rpm. If the hasn't dragged then, we know we are in for night.

If there is strong wind or current, we let the wind or current keep the chain form bunching up.

We¨ve been at anchor outside La Paz the past few weeks, the past three nights it ahs been blowing about 25-30 knots, Add to this an up to 3 knot reversing current and you've probably got every anchor manufacturer's nightmare.

WE have not moved an inch - we have 4:1 scope

Disclaimer - I have no interest in Mantus except as a very satisfied customer.

[boatman61]

Re Chotu's post.. my technique is to get to my chosen spot, drop the hook then gradually drift back with windage on main and Hull till I've paid out 10m then hold allowing the bow to swing head to wind then pay out another 10, repeat, then the last 10m by which time the anchor is sufficiently set 90% of the time.. I only use the engine to aid set if there is no wind to speak of.. boat weight is adequate.

[thinwater]

Originally Posted by ThereAndBack

Thank you for the feedback and indeed, I may want to experiment with adding more scope for this type of anchor, but I'm curious where you got the "only lay out 50ft of chain"?

Generally speaking I put out a 5 to 1 scope as measured by:
Depth x 5 + tide + 3ft (which is the height of the attachment points for bridle above the waterline).

In rougher weather I usually deploy 7 to 1 or more if it isn't crowded.

If I'm reading what you're saying, you drop the depth + 3 times boat length? For me that would mean paying out 40m of chain when anchoring in 2m depths?

You meant:


rode = 5 x (depth+tide+3)


In 6 feet of MLW with 3 feet of tide the first is 36, the latter is 60 (including the bridle).


You described this in an early post but didn't write out the math. The math is for others.

[ThereAndBack]

Originally Posted by thinwater

You meant:


rode = 5 x (depth+tide+3)


In 6 feet of MLW with 3 feet of tide the first is 36, the latter is 60 (including the bridle).


You described this in an early post but didn't write out the math. The math is for others.

Thank you for the correction. Yes, this is the correct formula.

[Smokeys Kitchen]

Hi There and Back,

We are a monohull, not a cat, but we also have a Vulcan anchor. We have lived aboard for 6 years now and are in our 2nd season in Mexico, having come from the Seattle area in Fall of 2021. We have been very happy with our anchor and can highly recommend it.

We trust our Vulcan completely and have only really had problems when I failed to properly set the anchor. Once was in Canada over a very rocky bottom and once was over mud in a very crowded anchorage. Both times we were at less than 3:1.

Our boat is a 40' cutter and our current anchor is a 33 kg Vulcan. I had origignally purchased a 25 kg Vulcan for our use, and that is what we had going up to Alaska when we dragged in Canada. Upon returning to the Puget Sound, I discovered my boat was @ 3,000 lbs greater in displacement (weight) than what I thought. It was through a strain gage on the Travel Lift when being hauled out - but it was the only data point I had so I upsized our anchor to the 33 kg one.

We have been pretty conservative when anchoring since then, and are almost always at 4:1 minimum and 5:1 wherever possible. Sometimes we don't like the set and bring the anchor back up and make sure it is clean before we do a re-set. We seem to accumulate a lot of 'fill' in the anchor on occasion and it hinders setting when that occurs.

We drop the anchor and chain to depth + @ 5 - 10 ft then start the backdown, just trying to lay the chain out and not pull on the anchor. We get to our desired length, including snubber, then pull gently on the chain just to straighten it out. Depending on the bottom, we let the anchor 'soak' a bit or just pull back with medium thrust and watch for any movement.

This has worked for us for a while now. We have encountered many (hundreds) of cruisers down here in Mexico and the variety of anchors and techniques is very large, but for the most part, the cruisers who are conscientious and a little conservative do not have setting or dragging issues.

Hope this helps a bit.

Ron
S/V Just Lucky