Leaving Your Boat at Anchor on a Windy Day

[endoftheroad]

As I have said in the past I want nothing to do with a danforth style anchor either, other than for use as a lunch or kedge anchor.
When I see a heavy cruising boat with a danforth hanging on the bowsprit I start looking for the captain to be wearing clean fashionable weather gear">foul weather gear and maybe a couple yapping poodles.

I have a fortress 23 that fits well on my pushpit, if it weren't for it's light weight it wouldnt be there.

[colemj]

Originally Posted by Jim Cate

Mark, I don't think that this is correct at all. Once the rode has stretched, if you continue to pull the full load is placed on the anchor... just like with chain. Just one of the reasons that one should back down for an extended period (say a minute or two) rather than just "bounce" on the rode.

Cheers,

Jim

Possibly, but most smaller engines on boats will not be able to hold a nylon rode tight, if they can even overcome the >20% stretch. A 5/8" nylon rode stretched bar tight will be ~1/4" in diameter. They will instead "rubber band" on it and not put much force on the anchor at all. Nylon is fantastic for not transferring full loads to the end fitting - that's why it is used for fall ropes, etc.

Actually, backing down puts less force on anchors than most people think. Even in full reverse on all chain. With two engines in full reverse, I estimate we get the equivalent force of 20-25kt winds on our boat (and we have a high windage catamaran). On the other hand, I think the forces on anchors in windy conditions are much less than most of us think - in 25kts of wind, I can pull our boat forward by just pulling in the chain cantenary in 10' of water and letting it reform. Snatch loads are something else, though.

And I agree with you about backing down slowly, continually and for an extended period.

But I don't think the OP's problem was in setting the anchor.

Mark

[Andrew Troup]

to Caracal:

Listen, buster, kindly don't go saying things like "This is not true" to justify a questionable semantic quibble, when addressing someone of the stature on this forum of GordMay.

(actually there's no-one of the stature of GordMay, he's unique)


He certainly could more completely have described anodising by inserting "electro-" in front of "chemical", but it seems to me his point was that it's not paint.


I frankly don't much enjoy reading many of your posts, even the ones where I agree with you: I'm in no position to ask you to tone it down, but I believe I'm free to tell you what I've told you.

[Caracal]

Originally Posted by Andrew Troup

to Caracal:

Listen, buster, kindly don't go saying things like "This is not true" to justify a questionable semantic quibble, when addressing someone of the stature on this forum of GordMay.

(actually there's no-one of the stature of GordMay, he's unique)


He certainly could more completely have described anodising by inserting "electro-" in front of "chemical", but it seems to me his point was that it's not paint.


I frankly don't much enjoy reading many of your posts, even the ones where I agree with you: I'm in no position to ask you to tone it down, but I believe I'm free to tell you what I've told you.

Wow, just wow. I really don't think anyone is untouchable as you would like them to be. I couldn't give a rat's arse about his "stature", and I care even less about your opinion on this.

I'm sure Gord can defend himself and are man enough to admit he was wrong on this detail without having sycophants declaring his every word off-limits.

Grow up.

Edit:
I actually don't want an "admission" of any kind, I corrected a detail, and I consider it dealt with.

[s/v 'Faith']

Everybody sing with me... "Can't you feel the love tonight... "

Peace,

[sabray]

Jeez Gord was mostly right gaurdisn is the same anchor but not anodized and doesn't have all features of a full fortress.. How we got to listen here and your wrong is beyond me.
As noted by fortress you need to have the right angle and dig the anchor in.
With a lot of chain and Bruce or Manson I can usually rely on a good lay out of rhode will hold. With a fortress I'm going to bury the thing with all the force I can. You'll know if its skipping or dug in usually.

[Caracal]

Originally Posted by sabray

Jeez Gord was mostly right gaurdisn is the same anchor but not anodized and doesn't have all features of a full fortress.. How we got to listen here and your wrong is beyond me.
As noted by fortress you need to have the right angle and dig the anchor in.
With a lot of chain and Bruce or Manson I can usually rely on a good lay out of rhode will hold. With a fortress I'm going to bury the thing with all the force I can. You'll know if its skipping or dug in usually.

FFS, I quoted very precisely what was wrong, yet you people continue on with this nonsense.

[capngeo]

Uh, guys.... Remember the "be nice" rule

[Jim Cate]

Originally Posted by colemj

Possibly, but most smaller engines on boats will not be able to hold a nylon rode tight, if they can even overcome the >20% stretch. A 5/8" nylon rode stretched bar tight will be ~1/4" in diameter. They will instead "rubber band" on it and not put much force on the anchor at all. Nylon is fantastic for not transferring full loads to the end fitting - that's why it is used for fall ropes, etc.

And I agree with you about backing down slowly, continually and for an extended period.

But I don't think the OP's problem was in setting the anchor.

Mark

Uhh, Mark,

There you are backing down on your rope rode. The 5/8 inch nylon has stretched so much that it is down to 1/4 inch diameter (not bloody likely, BTW). What is that nylon attached to that provides the resistance that you are pulling against? Well, the only thing out there is the anchor, so it must feel the full tension that you are putting on the upper end.

I won't argue about how much pull the average yacht can exert, but if you continue to pull until the rode stops stretching, the anchor will have all that pull exerted on it. It may or may not dig in, but it will have the full load applied.

And I agree that setting was not likely the culprit in the OP's situation.

Cheers,

Jim

[Kenomac]

I learned my lesson with a partial nylon rope rode three years ago on a Hunter 450. I anchored my oversized rocna using 50 feet of chain spliced to 80 ft of nylon rope, the splice was new and the bottom mud/sand. Following just three nights at anchor, when I pulled up the anchor, the splice was all chewed up and chaffed to the point where I would never trust using it again.

I've only used all chain rode since that lesson was learned. All it takes is a sharp rock, choral or some sumerged metal junk along with a moderate wind to cut through rope.

[noelex 77]

Originally Posted by Caracal

That's not true:

This is anodising:
Quote:
Originally Posted by WikiPedia
Anodizing (also spelled "anodising", particularly in the UK) is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts.


Anodizing - Wikipedia, the free encyclopedia

Anodising is commonly referred to as forming a chemical bond as opposed to the mechanical bond produced by paint.

I cannot find any indication in the references you quote to dispute this.

An electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts. Implies to me a chemical bond.

The Wikipedia also says:
Anodization changes the microscopic texture of the surface and changes the crystal structure of the metal near the surface.

Semantics aside, anodising is a great process that is under utilised on boats, I think because it is poorly understood.
One of my previous yachts had an anodised mast and boom, it was a much more practical finish than the painted one on my current boat.
The finish on my Fortress anchor is still in very good shape, its hard to imagine a paint could be anything like as durable, no matter how the finishes achieve their bond with the aluminium.

[Andrew Troup]

Checking my standards documents from Nadcap

(National Aerospace & Defense Contractors Accreditation Program -the body which certifies such contractors for Quality Systems)

the first twelve standards listed under

AC7108 Rev D - Nadcap Audit Criteria for Chemical Processing

all relate to anodizing.


Here's a webpage which has a similar list:

http://www.anoplate.com/nadcap


The specs which these guys patrol are used on space shuttles & stations, satellites, Hubble space telescope, interplanetary probes etc, not just military toys and civilian aircraft, so one would think they would choose their terms with reasonable care.

(even if they struggle with the spelling of Anodising and Aluminium ;-)

[Dockbound2long]

Thanks, Jacob , for fessing up. As a fellow career pilot I realize that you are a pretty darn careful guy or you would have augered in years ago.

Don't be put off by the piling on, some of these guys sound like chief pilots. Anchoring is like landing an airplane, there is a lot to it, and many variables.
The flight attendants used to score my landings by how many overhead bins popped open.

[Caracal]

All nice and well, but a "chemically bonded coating" more than implies that it is something that is put on afterwards (as in painted/rolled/dipped), when that is not the case.

[Kettlewell]

Again, I will repeat, that using a mixed nylon and chain anchor rode in the Chesapeake is perfectly safe and not unusual. In fact, I would argue that it is probably better. Those with all chain will spend a lot of their anchoring lives cleaning thick, black, and very stinky muck off of the chain, themselves, and the boat. One time in Annapolis outer harbor, while using all chain, the anchor was fouled and it took both my wife and myself working hard to get it up. There was no way to wash the chain on its way up because we were both doing other things. When we finally got it up we looked like we had been mud wrestling on the foredeck!

Also, I have used a Fortress numerous times in the Chesapeake deliberately instead of the main anchor, because I needed the extra holding power. Some of the bottoms there are very loose mud, and anchor surface area is your friend. Another trick in some of these places is to let a heavy anchor just sit without backing down first. If the wind is light the anchor will gradually sink through the ooze down to a layer where you might get some holding. If you immediately back down on the thing the anchor will just pull through the ooze and you'll back right out of the harbor.

This ooze also does a number on your scope. Your depth sounder reads 10 feet and you add 5 feet for the bow, so you put out 75 feet of rode to get 5:1. But, that 10-foot reading is just the top of the ooze. The real holding ground is probably another 10 feet down, so to reach that you need to put out 125 feet of rode to maintain your 5:1. The moral of the story is to use a lot of anchor rode in the Chesapeake.