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Old 19-03-2017, 15:45   #31
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Some of this makes sense, other bits not so much. Specifically:
Quote:
Originally Posted by thinwater View Post
The problem with high grade chain is that the shackles are basically unavailable above grade 43. And it will still be chain, when it comes to dragging on deck. Dyneema is better.
I'm thinking that titanium shackles would be up for the job when paired with higher schedules of chain. And if you're worried about dragging chain on deck, why not cover it with webbing as you're proposing to do with spectra rode.
A a leader, the solution is to cover it with a webbing chafe guard. No problem cleating to handle and break-out, based on experience.
So using a snubber is no longer "fashionable". This, assuming that you have enough chain on the anchor so that it reaches from the sea bed to the deck. Which isn't always the case, especially with short chain leaders.

You only overheat nylon if you are over the WLL. It would fail anyway. Additionally, At least I am proposing Dyneema only for the leader (20'); there will still be nylon. I am only replacing the chain, which ain't easy to cleat either.
I've seen plenty of docklines with melted line fibers where the line met the cleat, & in the course of some weather, the friction of the line moving on the cleat under load melted some of it's fibers. Though in no way was it ever even close to it's WLL. Not even remotely. Nor was there much, if any room for snatching loads on these lines.
Also, the chain cleating thing is a non-issue, for a number of reasons.

No one is going to use rigging wire. It's been discussed for 75 years (old Danforth documents) and no one is going to do it for obvious practical reasons (good luck cleating that for break out).

And no, Dyneema is not chain. I used Dyneema during some anchor testing around rocks, because it was something that needed testing. It didn't do badly, but after you watch rodes wrap around rocks it becomes obvious that chain the the best answer. I only use Dyneema/webbing for sand and mud. I have a 20' piece of chain I can swap.
What happens when the cordage has repeated real estate arguments with rocks & shells embedded in the sand & mud? And how does one know when/if such aren't present. If in fact this is ever actually the case? As few bottoms are homogenous.
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Old 19-03-2017, 20:46   #32
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Quote:
Originally Posted by UNCIVILIZED View Post
Some of this makes sense, other bits not so much. Specifically:
Mostly, I think I can address your points easily.

The problem with high grade chain is that the shackles are basically unavailable above grade 43. And it will still be chain, when it comes to dragging on deck. Dyneema is better.
I'm thinking that titanium shackles would be up for the job when paired with higher schedules of chain. Silly IMO, but that is only my opinion. And if you're worried about dragging chain on deck, why not cover it with webbing as you're proposing to do with spectra rode. Because a fat chain with a cover will not bury as well as a thin Dyneema rode with a cover. Based on testing of wire vs chain, this will probably cost 15-25% in holding capacity in soft mud compared to the Dyneema version. The covered Dyneema has a thinner profile than chain. It is also much lighter.
As a leader, the solution is to cover it with a webbing chafe guard. No problem cleating to handle and break-out, based on experience.
So using a snubber is no longer "fashionable". Sarcasm has made your meaning unclear. The leader is Dyneema and the rode is nylon, so a shock snubber is not needed. Perhaps this is misunderstanding. This, assuming that you have enough chain on the anchor so that it reaches from the sea bed to the deck. Which isn't always the case, especially with short chain leaders. I suggested 20', but that depends on your location. You could easily make it longer. In my world, I anchor in 5-7 feet 98% of the time, so the deck is 10 feet plus tide and an allowance for tide. If the water were deeper, I would be cleating the nylon so still no problem. We are trying to avoid cleating chain or naked Dyneema. Yes, chain can be snubbed with rope to avoid cleating it, but that requires several extra steps, whereas I can simply ahul in by hand as I glide over the anchor, cleat it the moment it is up-and-down in 2 seconds, and break the anchor out as I glide past it. Thus, I do not understand the criticism. Covered Dyneema is easier for breakout, period. I've used both.

You only overheat nylon if you are over the WLL. It would fail anyway. Additionally, At least I am proposing Dyneema only for the leader (20'); there will still be nylon. I am only replacing the chain, which ain't easy to cleat either.
I've seen plenty of docklines with melted line fibers where the line met the cleat, & in the course of some weather, the friction of the line moving on the cleat under load melted some of it's fibers. Though in no way was it ever even close to it's WLL. This is an estimate, not measured fact. I have done a lot of testing with load cells, and suspect that if there was internal melting, the load was over 9% of the breaking strength (that is the WLL for nylon). Alternatively, this is an external chafe problem, not the sort of internal melting that most people understand. Covered Dyneema is by no stretch of the imagination vulnerable to chafe. Not even remotely. Nor was there much, if any room for snatching loads on these lines.
Also, the chain cleating thing is a non-issue, for a number of reasons.

No one is going to use rigging wire. It's been discussed for 75 years (old Danforth documents) and no one is going to do it for obvious practical reasons (good luck cleating that for break out).

And no, Dyneema is not chain. I used Dyneema during some anchor testing around rocks, because it was something that needed testing. It didn't do badly, but after you watch rodes wrap around rocks it becomes obvious that chain the the best answer. I only use Dyneema/webbing for sand and mud. I have a 20' piece of chain I can swap.
What happens when the cordage has repeated real estate arguments with rocks & shells embedded in the sand & mud? And how does one know when/if such aren't present. If in fact this is ever actually the case? As few bottoms are homogenous. First, I have been using this rig for years. There are shells in the bottom, but unless they are fixed in some way, they simply move out of the way. Second, I said "kedge and V only." A kedge is short term and in a straight line, and a V anchor rig does not saw from side to side like a single anchor (which I specifically did NOT recommend--my primary rode is chain). Third, the rode is covered with a floating chafe guard; when it comes across a rock, it slides or rolls--the only motion or friction is between the Dyneema and the inside of the webbing. Finally, It is a simple matter to slide the webbing up once in a while and look. It takes only seconds.

Then there is the value of labor savings. If it is significantly easier to deploy, I save effort and time every time, which is worth money. I am more likely to use the anchor, which may add safety. If I need to move quickly (kedge) it is faster. If the life is shorter than chain... I don't care. I can replce it at the first sigh of wear (which has not yet happened in 2 years) and still be pleasantly ahead.

Thus, you are welcome to lug heavy chain around your deck for arguable increase in security (holding capacity is less, chafe resistance is greater), or you can use a system that is adapted to specific circumstances and anchor more easily. I described not an idea, but rather a system that I have been using successfully for several years. Not guessing--using.
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Old 19-03-2017, 22:56   #33
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Not sure what your definition of kedge is, but it doesn't sound like you mean a stern hook. In my neighborhood I have used a kedge, a small Danforth in my case, even when I was anchored bow and stern, in a small anchorage, to hold the boat away from someone or something. Usually this meant the kedge was in pretty shallow water that might have rocks so I used about 20 feet of chain since most chafe I find happens within that first 20 feet from rocks on the bottom and I usually have the last few feet of the chain up off the bottom. Or I might intentionally set it in rocks. If you know for sure you are over a clean sandy bottom, I don't see that chain is necessary. It is rare I do this but I have it just in case. Since this is something you will likely be deploying from a dinghy, it needs to be easily manageable. And you have to have a good way to pay it out off the dinghy as you return to your boat, you can't just throw it out there. A roller on the dinghy transom is not a bad idea as long as it doesn't interfere with anything. AND, since, at least in my case I have to retrieve it from the dinghy and it may be caught on a rock, I am ready with a trip line and buoy for the kedge. Since it is in shallow water, near shore, this buoy is not generally in water anyone else would be anchoring in. Not sure if this helps in your situation, mine is fairly specific to the local anchorages, but my $.02
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Old 19-03-2017, 23:22   #34
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

The only time I had to kedge off, I found the stretchiness of nylon 3-strand to be an advantage. Yes, there was a lot of energy stored in the stretch. So I winched in as much as I could, cleated it off, and wriggled the boat with motor and tiller while the nylon contracted a few feet. Lather, rinse, repeat.
I couldn't work the winch and the helm at the same time, but the nylon worked on "autopilot" thanks to the stretch.
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Old 20-03-2017, 04:41   #35
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Quote:
Originally Posted by thinwater View Post
The leader is 20' and is covered with 1-inch tubular webbing as a chafe guard.
Thinwater,

What is the 1" tubular webbing made of? Nylon, polyester, Spectra? I notice that on your web page you give a price of $25/ft. If it's Spectra, what was the source?
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Old 20-03-2017, 09:31   #36
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

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Thinwater,

What is the 1" tubular webbing made of? Nylon, polyester, Spectra? I notice that on your web page you give a price of $25/ft. If it's Spectra, what was the source?
$0.25/foot (I will correct the error). Nylon with a very tight weave. I'm not aware of anything in spectra that large that is hollow.

REI or any rock climbing store. New England Ropes Climbspec.
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Old 20-03-2017, 09:36   #37
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

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I'm not sure what you call it when you take an anchor from a halyard to drag yourself off a shoal...but I wouldn't call it kedging.

And I would want some stretch in that line...otherwise the shock (when force suddenly applied) could damage any of the hardware in between...which is your mast, stays, turnbuckles, cleats, etc.

sorry the proper terminology for removing self from the shelf is KEDGING off a shoal. is easy and fun. especially at night.
you will need a dinghy and or swim with the kedging anchorS and if you are lucky no one will see you as you accomplish this feat of brilliance.
any anchor is good for this, and rope works unless you are a fitness freak and LOVE raising often heavy chain and a heavy anchor. the goal is hull off shoal. easy peasy.

i keep a spool of 3 strand and 3 anchors--danforths and a cqr, expressly for this exact purpose. my boat came with 5 anchors plus cqr. hahahahaha. so far the cqr has worked perfetly for this
i guess the pos did not wish their erroneous anchoring plots visible
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Old 21-03-2017, 14:07   #38
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Quote:
Originally Posted by Factor View Post
You may fall for marketing hype, I don't.

Spectra creeps under prolonged heavy load and Dynemma doesn't, wonder how that is. It may not be relevant in the lower performance end of life, the difference is very noticeable on high performance multis. Thats actual real life experience, not internet truth.

Got a citation for that court proceeding reference?
How about DSM's website?

Designing with HMPE's Creep Property

HMPE fiber is sensitive to long-term static loads and will elongate proportionally with time. This phenomenon is known as creep, and is a process in which the long molecular chains slide along each other. Ever since the commercialization of our HMPE fiber back in the 1990s, DSM Dyneema has recognized the importance of creep in customer applications. It’s something we have focused on closely and the reason we have since run a program to determine how applications made with Dyneema® will behave when placed under long-term static loads.
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Old 22-03-2017, 05:03   #39
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Thanks Thinwater for the very informative posts.

I'm now thinking that there is no big advantage for me to change from 16mm 3 strand to include a dyneema or spectra leader. I could for example put a nylon webbing cover over the 16mm 3 strand and get added chafe protection.

If I did this then the situations where chain had the chafe resistance advantage would be greatly reduced....but not eliminated.

It might also be a good idea for me to go ahead and make a 10m leader of 10mm dyneema, put a webbing cover on it and try it out.

Thanks again
John
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Old 25-03-2017, 00:05   #40
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

There are smart ways to save weight on a boat and there are stupid ways to save weight on a boat. Skimping on ground tackle is stupid. Get a real anchor (not an aluminum tinker-toy held together with stainless steel screws) get a reasonable length of chain and a couple of hundred feet of adaquate nylon rope. Be safe and keep everybody else in the anchorage safe.
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Old 25-03-2017, 02:33   #41
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

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Get a real anchor (not an aluminum tinker-toy held together with stainless steel screws)
Oh-oh, now it's going to start.
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Old 25-03-2017, 03:14   #42
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

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There are smart ways to save weight on a boat and there are stupid ways to save weight on a boat. Skimping on ground tackle is stupid. Get a real anchor (not an aluminum tinker-toy held together with stainless steel screws) get a reasonable length of chain and a couple of hundred feet of adaquate nylon rope. Be safe and keep everybody else in the anchorage safe.


Thankyou Ingrid for you very informative post, I appreciate the time and effort you have put in to reading this thread.

Yes you are right that I should not use some aluminium tinker toy and after all these years of discussion on these forums, it is still not clear to me which one is the best, so I made a decision.....

As I'm a bit of a marina queen, I decided that I do not need any anchors at all, so I removed them. I save a lot of weight and when you think about it, what can really go wrong....

On the rear occasion that I do get caught out with no safe marina, I will sail over to one of you anchor experts safely and responsibly anchored in the bay and hand you my bow line... it's just for one night and I know you did a good job of selecting your ground tackle and setting it.
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Old 25-03-2017, 21:32   #43
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

Fuss, I appreciate your sarcasm, but I remember back in the 1970's when I was in the coast guard working at RCC Long Beach. We received a distress call from a boat which had lost power and was drifting ashore. We advised the skipper to set his anchor. He replied that since he only stayed in marinas, he did not carry an anchor!?! It seems that for a lot of people, the word "seamanship" is just something you see in an old C. S. Forester novel.
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Old 25-03-2017, 23:55   #44
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

If you were in the Coasties, perhaps you might have noted that they use those aluminium tinker toys as bower anchors on many of their vessels.

I guess they should listen to you and get "real anchors" instead... you know, ones that look like the ones embroidered on the funny hats that "real sailors" wear.

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Old 26-03-2017, 02:20   #45
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Re: Kedge Anchor with no chain and Spectra Dyneema rode.

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I guess they should listen to you and get "real anchors" instead... you know, ones that look like the ones embroidered on the funny hats that "real sailors" wear.
Jim
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