Anchor setup for serious crusing - anchor size for 25 foot, 2 tons (4500 pounds) yachts

[Neeves]

If my boat was veering or yawing (other descriptions are available) all over the place, and exerting shock loads on my bow roller, instead of worrying whether my anchor was the most fashionable, or expensive available, I would be doing something to prevent the veering or yawing. I accept, of course, that this is more difficult for those with lightweight boats, maybe particularly multihulls, which tend to skitter about in puffs of wind. I am the fortunate owner of a relatively heavy ketch, with more windage aft than the equivalent size of sloop. I'm also prepared to rig a riding sail, if the conditions merit its use.

Some times veering has nothing to do with the yacht - but a lot to do with topography and wind stability

You only need to look at aircraft coming into land and see them veering to appreciate wind instability - the average wind direction might stay stable but the wind can still veer. I don't think the pilot or auto-pilot are at fault - they are trying to keep and aircraft on the straight and narrow -sometimes without too much success.

When sea based wind farms are chosen one of the characteristics examined and measured is the susceptibility of the location of the wind farm to variation of the wind from the average - veering.

https://www.nrel.gov/docs/fy20osti/78107.pdf

In many anchorages because of gaps in tree coverage or valleys and gullies directing the wind you can have variation - and there is nothing you can do about it

Except evaluate where the majority of gusts are coming from and set 2 anchors (in a 'V' aka 'Fork') to cover the two dominant gust directions

If your yacht does yaw, for whatever reason - these are the implications for your anchor

Yawing and Anchor Holding - Practical Sailor

Jonathan

 

[[194497]]

This is probably just stating the obvious but worth remembering that lightweight anchors are good because anchor holding relates to anchor area, so an aluminium anchor, if well made, is likely to hold better than a steel one of the same weight.

 

[zoidberg]

I'm just idly wondering if, in the bad old days before internet, broadcast radio/TV, even fairly universal reading literacy..... the sailors with their horny hands, tarred pigtails, and homemade peajackets gathered in quayside alehouses debating endlessly the merits of respective anchors...?

Or were they more likely focussed on the next jug of rum, and the barmaids?

 

[vyv_cox]

I'm just idly wondering if, in the bad old days before internet, broadcast radio/TV, even fairly universal reading literacy..... the sailors with their horny hands, tarred pigtails, and homemade peajackets gathered in quayside alehouses debating endlessly the merits of respective anchors...?

Or were they more likely focussed on the next jug of rum, and the barmaids?

In those days anchoring was a considerably less reliable activity than it is today and anchors themselves fell apart fairly frequently so my guess is that it was often discussed.

 

[doug748]

Not my experience of my Rocna.

Indeed, I have a Rocna it works very well. Little bit tight in my anchor well but most newer anchors are. Hence for the past season I have been using an Epsilon which has also been ok but fits much better.

To drift the thread.
My one niggle with new anchor designs is the grossly inflated prices. The Delta is excellent value and one of the better constructed anchors retailing at 10Kg c £110, so why are some similarly constructed, simple steel fabrications, sub contracted from China 3 times the price?
We all suspect that the ex factory price of all of them is about 50 quid.

.

 

[vyv_cox]

To drift the thread.
My one niggle with new anchor designs is the grossly inflated prices. The Delta is excellent value and one of the better constructed anchors retailing at 10Kg c £110, so why are some similarly constructed, simple steel fabrications, sub contracted from China 3 times the price?
We all suspect that the ex factory price of all of them is about 50 quid.

.

In my book Metals in Boats there is a series of photographs provided by a forum member detailing the construction of a concave anchor. It is surprisingly complex, comprising many component parts. While I agree that the cost of anchors is higher than it might be, I doubt that £50 would cover their construction.

 

[NormanS]

Some times veering has nothing to do with the yacht - but a lot to do with topography and wind stability

You only need to look at aircraft coming into land and see them veering to appreciate wind instability - the average wind direction might stay stable but the wind can still veer. I don't think the pilot or auto-pilot are at fault - they are trying to keep and aircraft on the straight and narrow -sometimes without too much success.

When sea based wind farms are chosen one of the characteristics examined and measured is the susceptibility of the location of the wind farm to variation of the wind from the average - veering.

https://www.nrel.gov/docs/fy20osti/78107.pdf

In many anchorages because of gaps in tree coverage or valleys and gullies directing the wind you can have variation - and there is nothing you can do about it

Except evaluate where the majority of gusts are coming from and set 2 anchors (in a 'V' aka 'Fork') to cover the two dominant gust directions

If your yacht does yaw, for whatever reason - these are the implications for your anchor

Yawing and Anchor Holding - Practical Sailor

Jonathan

When you say that there is nothing you can do about it, I disagree (as you would probably expect).
I also study the topography, and use it to my advantage. If I expect severe wind strengths, I try to avoid anchoring behind high and/or steep ground, where gusts will be generated. If at all possible, I'll anchor behind low flattish land, where although the wind will be strong, it will be steadier, both in strength and direction. That's just one of the many items in my quiver of strategies, to reduce yawing, and shock loads. Granted, that's not always possible, but it's still a worthwhile policy.

 

[zoidberg]

I also study the topography, and use it to my advantage. If I expect severe wind strengths, I try to avoid anchoring behind high and/or steep ground, where gusts will be generated. .

It's not everyone who manages to think that way. I recollect a friend anchoring his 8m. Dragonfly 800 trimaran in the pool at Lock Scavaig - which has the steep rock faces of the Black Cuillin Ridge rising to over 3000 feet close adjacent - being most surprised when his boat simply got airborne in the violent downdrafts/'williwaws' that blasted downslope, lifting the surface water in sheets, underneath his woven-mesh fabric side decks - and flipping his 1100kg trimaran inverted in a couple of seconds.

This fellow developed a reputation for flipping larger multis - one very expensive 50' example in the Atlantic a day north of the Azores. They had the big racing screecher up and - temporarily, then permanently - no-one on the sheet and helm.

Edit: His anchor held. It was a steel Danforth....

 

[NormanS]

It's not everyone who manages to think that way. I recollect a friend anchoring his 8m. Dragonfly 800 trimaran in the pool at Lock Scavaig - which has the steep rock faces of the Black Cuillin Ridge rising to over 3000 feet close adjacent - being most surprised when his boat simply got airborne in the violent downdrafts/'williwaws' that blasted downslope, lifting the surface water in sheets, underneath his woven-mesh fabric side decks - and flipping his 1100kg trimaran inverted in a couple of seconds.

This fellow developed a reputation for flipping larger multis - one very expensive example in the Atlantic a day north of the Azores. They had the big racing screecher up and - temporarily, then permanently - no-one on the sheet and helm.

.

Yes, Loch na Cuilce, the name of that inner pool in Loch Scavaig, is an excellent example. It's perfectly sheltered from any sea, has mainly a clean mud bottom, but is one of the last places on this Earth to anchor in heavy weather. In a F6 from the SWly, quite common in the area, the wind in the anchorage becomes a gusty F8 SEly.
In any fresh or stronger winds from the Nly quadrant, severe gusts come down vertically. It is then very much better to go a mile to the east, and anchor off the east end of the beach at Camusunary. There the wind will still be strong but steady in both strength and direction. I could give innumerable similar examples in the NW. It's not rocket science, merely applied common sense.

 

[noelex]

When you say that there is nothing you can do about it, I disagree (as you would probably expect).
I also study the topography, and use it to my advantage. If I expect severe wind strengths, I try to avoid anchoring behind high and/or steep ground, where gusts will be generated. If at all possible, I'll anchor behind low flattish land, where although the wind will be strong, it will be steadier, both in strength and direction. That's just one of the many items in my quiver of strategies, to reduce yawing, and shock loads. Granted, that's not always possible, but it's still a worthwhile policy.

This is a good point that is often overlooked when selecting an anchorage. Anchorages surrounded by high hills are also sometimes small, giving limited room if you do drag.

Another consideration is whether or not you may be safer in a less protected, but less crowded location. When bad weather is forecast often the more protected anchorages become crowded even in Scotland. I aways consider the biggest risk is other boats dragging into our vessel so if you have good anchoring gear a less protected anchorage or location within the anchorage may sometimes be the better choice.

 

[geem]

This is a good point that is often overlooked when selecting an anchorage. Anchorages surrounded by high hills are also sometimes small, giving limited room if you do drag.

Another consideration is whether or not you may be safer in a less protected, but less crowded location. When bad weather is forecast often the more protected anchorages become crowded even in Scotland. I aways consider the biggest risk is other boats dragging into our vessel so if you have good anchoring gear a less protected anchorage or location within the anchorage may sometimes be the better choice.

So many times we have anchored in a large bay on our own and then had another boat come in and anchor right next to us.

 

[NormanS]

So many times we have anchored in a large bay on our own and then had another boat come in and anchor right next to us.

Yes, I remember being anchored in one of the outer bays in West Loch Tarbert, Jura. We were climbing the three "Paps of Jura", and watched from the hill as boat come into the large, wide, unobstructed bay, and anchored within spitting distance of us. ?
I suppose you could take it as a sort of a compliment, in that they must have thought that we knew what we were doing. ?
We left them to their solitary splendour, as we were going further in to better shelter for overnight.

 

[zoidberg]

So many times we have anchored in a large bay on our own and then had another boat come in and anchor right next to us.

Boatys' 'flocking behaviour'....? Squeezing together for fear of marauding Hielan' 'anchor fees' collectors?

 

[Farmer Piles]

In reference to shifting winds:
We were on holiday in New Zealand a few years back and we did an overnight on Doubtful Sound on a 65ft aluminium mobo. It is a narrow sound and the mountains tower thousands of feet almost vertically. It was a single engined boat, and when we got back to the jetty the skipper told the crew, a 17 year old lad, to put on a stern rope and then just put the boat on full lock with the engine in forward gear. We were ashore when a gust swirled around around, took the bow off the jetty and swung the boat out in an arc like a ball on a string. The stern line was taught and the skipper failed to react in time. In seconds the stern line was cutting through the superstructure of a 35ft sports fisher moored behind. The lad grabbed a machete and chopped the line as the mobo was about to hit the sports cruiser, the rope had cut nearly half way through the superstructure. All in less than 30 seconds.
It was pretty dramatic watching it all from a vantage point ashore.
Swirling, shifting winds and complacency.

 

[Neil_Y]

There is no discrimination between a single deck powerboat or a sailing vessel. Is a sailing vessel unusually high windage. We have two masts but flush decks. Are we unusually high windage? Really open to interpretation.we aren't a square rigger?

The Blue code is for sailing vessels not motor vessels

 

[Neeves]

To drift the thread.
My one niggle with new anchor designs is the grossly inflated prices. The Delta is excellent value and one of the better constructed anchors retailing at 10Kg c £110, so why are some similarly constructed, simple steel fabrications, sub contracted from China 3 times the price?
We all suspect that the ex factory price of all of them is about 50 quid.

.

Delta, Rocna, Vulcan, Epsilon and Kobra etc are all cast (and made in China). There is still some welding and galvanising. I'd guess that most of the Chinese fabricators also have their own galvanising (but my guess maybe way out).

I do agree a simple cast fluke welded to a bit of steel (for the shank) should not cost too much.

Excel is made from a number of steel plates welded together by hand and the ballast is cast steel, off site,l into the ballast chamber. The anchors are made in Australia from Australian steel. Supreme is made in NZ from component parts rolled, for the fluke, using one of 3 rollers. Manson are a big maritime fabricator and may galvanise on site. Knox is made from pieces of steel plate, welded, in Scotland and I assume uses UK steel. Galvanised off site. Spade is fabricated in Tunisia from component parts, welded by hand and the lead cast into the ballast chamber. It is unusual for an anchor maker to have in-house galvanising and the fabricated anchors need to be sent to an independent galvaniser, prior to the addition of any ballast. Viking are made in Ukraine using high tensile steel from Scandinavia, welded by hand. They are then delivered with some difficulty to the 'free' world. Fortress is made from USA aluminium extruded using custom made dies, anodised in a local sub contractor and finished off by hand in Florida. Shipping of anchors round the world is expensive

None of this is very efficient - but the volumes are small - you pay for all the offsite production in addition to the anchors effectively being hand and custom made.

If you are concerned at value for money - maybe support those who do make by hand.

Excel, Fortress, Spade etc, you need to check the complete list, have been certificated by a Classification Society for performance, commonly Super High Holding Power, this needs to be verified on a regular basis to keep the Certification valid. Anchors used on commercial vessels in survey will need a valid and up to date certificaion. Validity is unnecessary for leisure anchors but appears to be deemed a good marketing wheeze - though the certificated may no longer be valid.

It all costs money.

Jonathan

 

[doug748]

" Delta, Rocna, Vulcan, Epsilon and Kobra etc are all cast (and made in China). There is still some welding and galvanising. I'd guess that most of the Chinese fabricators also have their own galvanising (but my guess maybe way out). "


You got to sort this out, its misleading. The only one piece, cast anchor design I can think of is the excellent original Bruce and the multitude of orrid copies. I'm sure they are others and some that use cast components but that list is very dodgy.

.

 

[zoidberg]

.....Viking are made in Ukraine using high tensile steel from Scandinavia, welded by hand. They are then delivered with some difficulty to the 'free' world....

While idly exploring the Viking gallery, did I spot the far-famed catamaran 'Josephine' - or did I imagine it? And some other bits and bobs with an Antipodean flavour to them...?

 

[roaringgirl]

Our boat is a 12T 42ft ketch. Our main anchor is a 25kg Rocna with 80m of 10mm chain. It has done remarkably well - its biggest challenge was in Fatu Hiva. The anchorage is 25m deep, so our scope was a little over 3:1. We had 55kt catabatic winds from 3 directions and she held just fine.

I am switching to an aluminium Excel before we depart NZ for the UK as it's hard to take the Rocna off the bow roller to stow in the locker for long passages and it has destroyed several large steel pins as it slams into the waves.

 

[vyv_cox]

" Delta, Rocna, Vulcan, Epsilon and Kobra etc are all cast (and made in China). There is still some welding and galvanising. I'd guess that most of the Chinese fabricators also have their own galvanising (but my guess maybe way out). "


You got to sort this out, its misleading. The only one piece, cast anchor design I can think of is the excellent original Bruce and the multitude of orrid copies. I'm sure they are others and some that use cast components but that list is very dodgy.

.

I don't think Jonathan said any of them are one-piece castings. The fluke of a Rocna is a casting, subsequently welded. I assume the toe of the Delta fluke is a casting, not sure about the others.