Obsessed with anchor snubbers

[patagoniadave]

Originally Posted by GordMay

It’s called an anchor sentinel, or kellet.
Most authorities discount their usefulness.
Eg ➥ https://www.petersmith.net.nz/boat-anchors/kellets.php

Cool read, thank you for the link!

Next I will do a deep dive on double anchors......

[thinwater]

Originally Posted by GordMay

It’s called an anchor sentinel, or kellet.
Most authorities discount their usefulness.
Eg ➥ https://www.petersmith.net.nz/boat-anchors/kellets.php

Particularly on chain rode, where simply using 20-30 feet more chain will have the same weight, be more effective, and easier to handle. More work for less effect.



They do have uses on rope rode, mostly for keeping the rope below the keel, and reducing yawing relative to boats with chain. But not on a chain rode.

[patagoniadave]

Originally Posted by thinwater

Particularly on chain rode, where simply using 20-30 feet more chain will have the same weight, be more effective, and easier to handle. More work for less effect.

Makes sense. After reading the pdf on the reply above, I am guessing that the reason there is a kettle in the stern locker, is to be used in conjunction with the second anchor back there for stern anchoring.

[thinwater]

Originally Posted by patagoniadave

Cool read, thank you for the link!

Next I will do a deep dive on double anchors......

In many ways they are similar to kellets; special purpose and not applicable 95% of the time. There are some uses for V-twin and anchors, and a very few specialized uses for in-line tandems.


For example, see if you can find an image showing BOTH anchors in an in-line tandem properly set, in a real world setting where the boat yaws in the wind (oil platforms don't count). I don't think you will. The only images are staged on beaches, and they are not, in fact, fully set.

[patagoniadave]

Originally Posted by thinwater

In many ways they are similar to kellets; special purpose and not applicable 95% of the time. There are some uses for V-twin and anchors, and a very few specialized uses for in-line tandems.


For example, see if you can find an image showing BOTH anchors in an in-line tandem properly set, in a real world setting where the boat yaws in the wind (oil platforms don't count). I don't think you will. The only images are staged on beaches, and they are not, in fact, fully set.

I did see a post about in line double anchors yesterday when I was researching snubbers, but what I was talking about is anchoring with two anchors, on different ends of the boat. Seams I read something about that somewhere, and am now curious.

[davefromoregon]

I have an 11,000 lbs 35’ sailboat with 130’ of chain, 140’ of rope, and a 20kg anchor. If I’m not using all of the chain, it is because it is relatively shallow and there isn’t a lot of wind.

If I’m using all of the chain and some amount of rope it is because it is deeper and there is a fair amount of wind. In that case, do I need a snubber?

[rslifkin]

Originally Posted by davefromoregon

I have an 11,000 lbs 35’ sailboat with 130’ of chain, 140’ of rope, and a 20kg anchor. If I’m not using all of the chain, it is because it is relatively shallow and there isn’t a lot of wind.

If I’m using all of the chain and some amount of rope it is because it is deeper and there is a fair amount of wind. In that case, do I need a snubber?

With a mixed rode (rope spliced to chain) I generally figure that as long as you've got at least 20, preferably 30 feet of rope deployed, there's no need for a snubber, as the rope provides stretch.

[Sailbaum]

I'm curious whether anyone has tried tow recovery rope for a snubber - designed for high stretch. I believe they are usually 20-30% stretch and available in set lengths with an eye at each end. Too stretchy?

[leecea]

With a mixed rode (rope spliced to chain) I generally figure that as long as you've got at least 20, preferably 30 feet of rope deployed, there's no need for a snubber, as the rope provides stretch.

You could add a snubber as a backup, even if it isn't needed for stretch. On one occasion we had a buddy boat who lost their anchor in the night when the nylon section of their rode parted. It was a very bouncy anchorage and we don't know why their rode snapped, but I always wonder if a "snubber" attached with a rolling hitch would have saved the day. At least they might have felt the primary rode snap and jerk the boat as the snubber came under tension. Maybe it wouldn't have held but we have always added a second line because of this.

[Benz]

Originally Posted by davefromoregon

I have an 11,000 lbs 35’ sailboat with 130’ of chain, 140’ of rope, and a 20kg anchor. If I’m not using all of the chain, it is because it is relatively shallow and there isn’t a lot of wind.

If I’m using all of the chain and some amount of rope it is because it is deeper and there is a fair amount of wind. In that case, do I need a snubber?

You want a sacrificial snubber--doesn't have to be all stretchy--just to save your rope rode from chafe. When I'm riding on a long rope rode on my storm anchor, I take the strain off the rode with an old dockline tied with a rolling hitch. The dockline can chafe all day, if it wants, and the rode remains in good nick. If the snubber parts, the primary rode is still in place.
I've parted a snubber in a blow, but never one on a rope rode--it was in shallow water with a chain bar-tight.

[GordMay]

Originally Posted by Sailbaum

I'm curious whether anyone has tried tow recovery rope for a snubber - designed for high stretch. I believe they are usually 20-30% stretch and available in set lengths with an eye at each end. Too stretchy?

Good question. I don’t know what the ideal stretch ratio, for a snubber, might be.

There’s going to be a trade-off, between the [desirable] shock absorption, at the elastic end of the cycle, and the [undesirable] snatch load, imposed at the recovery end of the cycle.

When on all chain [or very nearly so], I [effectively] used a 3/8" or 7/16" dia. [?] Nylon rope snubber [on 3/8" chain + 5/8" rope], with a stretching ratio of about ± 20%.
IDK how close to ‘ideal’ that might have been.


Snubbers, tow ropes,, and recovery ropes [each] have different purposes, and, hence, different [ideal] charcteristics.

Low stretch [3% ➛ 15% ratio] static tow ropes are safer, than dynamic recovery ropes, because they will not recoil, dangerously, if broken.
High stretch [±30% ratio] dynamic [kinetic] recovery ropes provide a dynamic snatch, aiding in recovery. The ability of a Kinetic Recovery Rope to stretch, is what sets it apart, from a non-elastic tow rope or tow strap.

The snubber is intended to stretch, providing shock absorption; however, on the other end of the stretch-recover cycle, do we want to apply a snatch load, to our anchor?

[carstenb]

Wow. I wonder where some of all you anchor. WE've been over a goodly portion of the world and have anchored perhaps over 2000 nights. We have a 30KG Mantus on 10mm chain and we use a Mantus snubber.

We have only ever dragged once and when we are anchoring, many stop and look at the "industrial strength" snubber we deploy. We have anchored in up to 50 knots of wind and 3-4 meter swells without issue regarding the anchor (it wasn't pleasant).

We sleep soundly at night and really don't worry.

[Pete7]

Originally Posted by carstenb

Wow. I wonder where some of all you anchor.

Oh that's easy . In a 5 Tonne yacht we don't anchor in anything over F4, it's just too bouncy. Instead we seek shelter in a harbour or marina and tie up to something solid, "We sleep soundly at night and really don't worry".

We do deploy a 10m snubber because it stops the chain grinding back and forth on the GRP deck and reduces the jerky motion.

This is what we want

Should I mention the anchor ball

Pete

[Kettlewell]

Wow. I wonder where some of all you anchor. WE've been over a goodly portion of the world and have anchored perhaps over 2000 nights. We have a 30KG Mantus on 10mm chain and we use a Mantus snubber.

Well, there are many different anchorages and many different anchoring situations that require different techniques. For example, here on the East Coast of the USA it is very rare that I anchor in more than 15-20 feet of water south of Maine, and often I am anchored in 10 feet or less. Usually, I can get into a place with 360-degree protection if a blow is to be expected, but OTOH there have been times when it is blowing a gale and the anchorage is getting 3-4 foot or more seas rolling through. No matter how much chain you have out it will straighten out and you will regret it. Put on a long stretchy snubber and you will reduce the loads on your anchor gear tremendously, and improve the comfort onboard. I've been in this situation in the Bahamas where there was no shelter at all, except for the shallow water all around, like on the Bahama banks. Even with a long stretchy snubber things were nasty, but at least the cleats weren't pulling out. I spent many years anchoring with only 50 feet of chain and then nylon and I almost never used a snubber because you can just deploy more nylon if you need more stretch. Despite it not being the cool stuff that people use today I never had a chafe problem using clear PVC tubing over the line where it went over the roller, up to and including hurricane force anchoring.

[OZwingle]

Originally Posted by rslifkin

With a mixed rode (rope spliced to chain) I generally figure that as long as you've got at least 20, preferably 30 feet of rope deployed, there's no need for a snubber, as the rope provides stretch.

)



Even so, I always deployed a snubber onto the 8-plait nylon. Two reasons. 1 Nylon rode is then left engaged in dual chain gypsy, yet load is taken to mooring cleats, off the windlass as recommended. 2 any chafe is taken by snubber, which is easy and cheap to replace, not chafing a spot on 70 meters of expensive 8-plait. Bonus 3 I used a snubber bridle, which seems to reduce swinging and sailing on the anchor.