Snubber question

[C lectric]

At anchor I have , as described above, used these rubber anchor snubbers and under some circumstances I have seen mine stretch enough that it is definitely working.

I first used them when we overstayed our weather welcome, 20-25 yrs ago, at a marina in Howe Sound.

The Northerly winds picked up overnight to about 50-60 K and we were being slammed around. THere was no way I was leaving the dock as I would have been slammed into other boats. The shock loads were enough the boat was leaning smartly and jerking HARD as the line stopped it from any further movement.
The day before I had seen the snubbers at the chandlery at the dock head so I went and bought one and installed it on a spare line which I could then secure the boat with.
As soon as that snubber came into play it smoothed out the snatch and no more jerking.

I went and purchased the other snubber.

THere have been other times they have come into play to take the snatch out of the lines coming up hard at the dock.

And mine are Taylor. I looked when I was at the boat.

 

[mvweebles]

I'm an awful fisherman so my numbers may be off, but I recall that very large fish- 300 lbs - have been landed on 50-lb line. I don't think using a coil spring that provides 18-inches of resistance (the rubber inline gizmo) brings the same level of elasticity that 20-feet of 3-braid does. Only a hunch.

Peter

 

[SteveK]

I'm an awful fisherman so my numbers may be off, but I recall that very large fish- 300 lbs - have been landed on 50-lb line. I don't think using a coil spring that provides 18-inches of resistance (the rubber inline gizmo) brings the same level of elasticity that 20-feet of 3-braid does. Only a hunch.

Peter

Peter, the trick is not to go over 50lbs, you release line, fish tires, reel in. eventually you have a tired fish in the net or gaffed.

with anchor, you have a fixed point. Suppose you could let anchor out on surg and take it in. NAW, use a snubber.

The snubber only needs to take the hit so the windlass, the pulpit etc do not have to. If it breaks start over, the boat is still attached to the anchor.

 

[Simi 60]

1/2 inch 3 strand nylon as a bridle is plenty.
Has anyone ever broken a snubber or bridle?
I don't bother with splicing, a bowline with duct tape on the tail is all you need.View attachment 137700

Yes, more than once
And on 20mm nylon , a bit over 3/4 inch

 

[psneeld]

Snubbers are consumables...their function is basically sacrificial based on what some have said...stretch is good, but shortens life.

Using one size fits all because worry of breaking makes no sense to me. If you want stretch, you have to size to expected conditions (wind/wave/surge). You do have to minimize chafe as that could prematurely weaken breaking strength too much.

If it breaks, tie/shackle on another and let out some chain. If conditions change THAT much overnight, you will probably wake up and can upsize your snubber.

As the saying goes.... "it ain't rocket science".......

 

[ranger58sb]

Greetings,
Where does this fit into the equation, if at all?

We've used those a couple times, when securing at the dock for hurricane-force winds.

I think there's a "sweet spot" number of wraps, which varies depending on reason for use. Without a lot of dock space in a 4-way slip, for instance, fewer wraps might keep the boat from bouncing off the timber.

Ditto, maybe the number of wraps might vary if used in an anchor snubber or bridle... offering some choice about what line (e.g., smaller cheaper; 3-strand cheaper) and how much stretch you need in your system.

Maybe.

-Chris

 

[jleonard]

I always used a single 1/2 inch 3 strand snubber. Was perfect, in my opinion, for my 40 ft Albin.
Used one for many years, never broke it.
I did carry a 5/8 one and used it once or twice, but it didn't have enough stretch.

 

[Bacchus]

I've used those for dock lines in high surge areas. Personally, I think they are a bit too elastic for use as a snubber, though fewer wraps around the rubber core results in less shock absorbancy so maybe there is a happy medium. But maybe someone has used one for a snubber and has a different perspective.

Peter

I have had a fair amount of experience w these on dock lines. Before our marina was rebuilt some of the slips experienced uncomfortable surges and most used 6 on the dock lines. You can "adjust" the flex (spring constant) but it's a trade off...
Fewer wraps less flex - harder on cleats & lines but easier on the snubber
More wraps more flex - easier on cleats & lines but harder on the snubber
I used to see an avg of 1 / season break under severe surges.

Marina rebuild solved the problem rather well and snobbery not req'd. [emoji16]

 

[rslifkin]

Snubbers are consumables...their function is basically sacrificial based on what some have said...stretch is good, but shortens life.

Using one size fits all because worry of breaking makes no sense to me. If you want stretch, you have to size to expected conditions (wind/wave/surge). You do have to minimize chafe as that could prematurely weaken breaking strength too much.

If it breaks, tie/shackle on another and let out some chain. If conditions change THAT much overnight, you will probably wake up and can upsize your snubber.

As the saying goes.... "it ain't rocket science".......

Agreed, 2 sizes of snubber makes sense in my mind. Shorter / thinner for good weather, thicker / longer for rough weather.

 

[Hippocampus]

I’m reminded of the events that occurred near Pete some years ago. A collection of boats both power and sail were lost. Even more dragged.
Several boats had snubbers attached to the forward cleats but also multiple snubbers attached elsewhere. Either they broke or their attachment points broke. Some even had their entire bow pulpit torn away.
My understanding was its was much like when you fall while rock climbing. One snubber or attainment point falls and the sudden loading of the next one causes it to fail as the force is much greater as the boat surges backwards.
Some suggest if their snubber(s) fail they will replace them and let out more chain. Well you’re a better man than me Gunga Din. There’s no chance I’m going to go up on a foredeck in those conditions and do anything useful other than putting myself at risk of injury or death. Also if your attachment points have pulled out +/or the bow of the boat has been destroyed think you’re sh-te out of luck.
My windlass has a lock we use it so there’s no force on the gearing. It has decent backing plate but with repetitive loading I guess the the deck could fail. Same with my cleats. I’d rather my snubbers be a wee bit weaker than my cleats. My chain a bit stronger. Can do much to beef up my windlass other than buying a new one.
Think some of this discussion doesn’t account for failure points in extreme conditions. Think it’s important to pick your anchorages very carefully. They say a chain is as strong as its weakest link . Think that teaching needs to be extended to your entire ground tackle and its attachments. Putting on a super strong snubber when the cleat will fail first makes no sense. Running a snubber over the roller in the pulpit or sprit unless it’s super strong makes no sense. My flexes if we have a reall stuck anchor. Think it would fail in a sustained 50-60kt blow with a snubber across it.

Need to think about the whole shebang. Not just the snubbers. Don’t think for many boats you can prevent disaster without major rebuild of your boat.

 

[cafesport]

1/2 inch 3 strand nylon as a bridle is plenty.
Has anyone ever broken a snubber or bridle?
I don't bother with splicing, a bowline with duct tape on the tail is all you need.View attachment 137700

I have broken, worn out and otherwise destroyed a number of snubbers, that’s how I learned what doesn’t work.

Fwiw using bowline loop instead of a proper splice will significantly reduce your line’s strength. This happens because knots lock the fibers from moving inside of the knot. This is made worse when the lines get wet. Nylon is hydrophilic so it’s dimensions change as it absorbs water. When you lock the strands from movement the load is transferred to the outermost fibers on the one strand that can move the most. When the strand fails, its next strand up. Go to your rope manufacturers website they usually show splice strength and wetted strength specs. For most 3 strand it’s about 90 percent of max breaking strength for plait it’s actually stronger than the line itself.

As hippo mentioned all chain rode means having a proper chain stopper that is not a snubber. Most boats these days mount windlasses too far forward to fit one so if you can’t install one you’ll want to improvise one in addition to a snubber. When we anchor up expecting strong winds, we use multiple snubbers, multiple points of attachment and an actual chain stopper.

 

[motion30]

Something to consider while you're buying line. if it's three strand or eight plat it's not going to last forever. I find regular replacement about every 2 years is common. It chafes on the chain it chafes against the deck and one good storm can require a replacement. Nothing wrong with three strands and it is more economical. Of course it's your choice. To qualify my comment I live aboard full-time on the hook

 

[GoneFarrell]

Motion,
Besides inspection for chafe and wear as you suggest is there a way to measure stretch of 3 strand as a percent of length, would that be relevant? I am used to measure roller chain stretch/wear on motorcycles and industrial drives, but not lines.

I am going to build a bridle for my boat, having been through the chain snatch/anchor reset lesson in 40 knots at night, no fun!

 

[DDW]

After stretching under load, nylon line returns more or less to the same length. The wear isn't like wear on a roller chain which is a permanent change to dimension. Rather is it friction between the strands chafing them (melting them, in extreme cases) resulting in a loss of ultimate strength. Dacron and high tech lines suffer much less from this, because the stretch is much lower - but that also makes them less desirable as a snubber.

 

[darkside]

Fwiw using bowline loop instead of a proper splice will significantly reduce your line’s strength.

Yes I am aware of the lower breaking strain with a knot. With a 1/2 inch bridle on a boat that weighs around 9,000kg I have so much in reserve it's irrelevant.
On the 46' sail cat we circumnavigated we had a very similar set up and never even thought of it breaking. Love the stretch.
The width of the bridle base on a cat also keeps the boat head to wind very nicely.
None of the yawing all over the place you see on some monohulls.
I wonder if that reduces the shock loading on the bridle?

 

[Capt Ray]

Some pics of our snubber...

We like.

https://shellerina.com/2020/09/21/splicing-8-plait/

I agree that a splice is 100% better than a knot...

 

[CarlF]

A snubber is a consumable that should be replaced every couple of years - or sooner if it’s been through a storm. The nylon weakens after repeated stretching and salt crystals will abrade the internal fibers.

A stretchy snubber will make your anchor less likely to drag by reducing the shock loads. This is especially important if your boat swings at anchor. As it reaches the end of a swing before turning back there is a quick sharp increase in load that can be reduced by the stretch of the snubber. You can observe this loading just by watching the anchor chain straighten at the end of each swing. Of course this load reduction will also reduce the load on cleats and chain.

To get enough stretch to dissipate surge you need to pick a diameter that is not so big that it won’t stretch but not so small that the line breaks. The most important thing is to use a long enough snubber. Most people’s snubbers are far too short - mine is 20ft so that after putting several feet on the cleat there is still 15’ left to do the job.

Really any nylon line is fine but 3 strand is cheaper and that’s good if you are replacing it regularly.

In storms I rig two snubbers with one about a foot looser than the other. This way the first snubber will stretch to a certain point before it gets help from the 2nd snubber.

And don’t forget chafe protection for your snubber if it goes through a chock or rubs against anything.

 

[Hippocampus]

Carl if you have snubbers with equal length deployed they will share the load and spread the load between attachments points. If one’s looser the first will break when overloaded. Then sudden loading will either break the other one as well or pull out its attachment. Also a bridle with both arms loaded will decrease hunting. Hunting increases the loading on the entire ground tackle system including the anchor. Have always adjusted things so both arms are equally loaded. In storm settings have tied an additional snubber to the chain close to the chain hook and brought that to yet a third different attachment point. Have the third share the loading from the get go. Snubbers stretch more in those conditions so don’t worry about getting enough stretch.
As a prior rock climber was taught to put your expansion bolts or other attachments close enough together that they wouldn’t sequentially rip out due to the increase in sudden loading if they were too far apart allowing you to fall more and increase the force involved. Maybe a difference of a foot is a small enough difference with your set up but personally don’t see what you gain.

 

[Bmarler]

Carl if you have snubbers with equal length deployed they will share the load and spread the load between attachments points. If one’s looser the first will break when overloaded. Then sudden loading will either break the other one as well or pull out its attachment. Also a bridle with both arms loaded will decrease hunting. Hunting increases the loading on the entire ground tackle system including the anchor. Have always adjusted things so both arms are equally loaded. In storm settings have tied an additional snubber to the chain close to the chain hook and brought that to yet a third different attachment point. Have the third share the loading from the get go. Snubbers stretch more in those conditions so don’t worry about getting enough stretch.
As a prior rock climber was taught to put your expansion bolts or other attachments close enough together that they wouldn’t sequentially rip out due to the increase in sudden loading if they were too far apart allowing you to fall more and increase the force involved. Maybe a difference of a foot is a small enough difference with your set up but personally don’t see what you gain.

I think it’s the same school of thought as an overload spring on a truck. Sort of a progressive loading concept. The idea would be that the second snubber starts taking load well before the breaking point of the first one.
I haven’t tried this approach, nor do I know if it works in reality, but I understand the concept.
The question would be how to set them for proper loading so the first one doesn’t break before the second one shares the load.

 

[CarlF]

Carl if you have snubbers with equal length deployed they will share the load and spread the load between attachments points.

I’m trying to accomplish something a bit different. The slack snubber is a larger size. Stronger than the breaking strength of the chain. I only use in storm conditions. I like the regular snubber to stretch easily at first to reduce loads in normal weather but at about 50% of breaking strength the bigger snubber comes into play to avoid breaking the first snubber. And if the first snubber should break, the larger 2nd snubber can handle the entire load.

On my boat I didn’t find that two snubbers substantially reduced yaw. I don’t know why. At each end of the yaw one snubber would be slack and the loaded snubber would carry the full load as the bow snaps around to go the other way. So there wasn’t any “sharing” going on when the load was highest. on a boat design where two snubbers reduced yaw (or that didn’t hunt in the first place) then that would be a good approach.

 

[Hippocampus]

Different boats different folks and differences solutions. Makes sense now.

 

[psneeld]

I’m trying to accomplish something a bit different. The slack snubber is a larger size. Stronger than the breaking strength of the chain. I only use in storm conditions. I like the regular snubber to stretch easily at first to reduce loads in normal weather but at about 50% of breaking strength the bigger snubber comes into play to avoid breaking the first snubber. And if the first snubber should break, the larger 2nd snubber can handle the entire load.

On my boat I didn’t find that two snubbers substantially reduced yaw. I don’t know why. At each end of the yaw one snubber would be slack and the loaded snubber would carry the full load as the bow snaps around to go the other way. So there wasn’t any “sharing” going on when the load was highest. on a boat design where two snubbers reduced yaw (or that didn’t hunt in the first place) then that would be a good approach.

I used to do the same thing with 2 unequal length snubbers for heavier weather. For less than 20 knots one small one was good enough.... then I would add the second then larger as it got windier/rougher.

I never worried about attachment points, only chafe so I generally preferred to run them over the bow roller like any single snubber. My boat wandered the same if not more on a bridle. But that can be different than a lot of boats , but it worked for me.

 

[chanprr]

Lots of good posts on this subject. I have always used a bridle on anchor, but a single line through the roller would make setting a snubber a little easier. The weather is always a consideration in the PNW and a bridle seems a safer way to go.

 

[psneeld]

Lots of good posts on this subject. I have always used a bridle on anchor, but a single line through the roller would make setting a snubber a little easier. The weather is always a consideration in the PNW and a bridle seems a safer way to go.

Safer in what way?

Backup, planning for the weather, etc, etc?

A single with a plan is just as safe.

Mainstream isnt alway the right path... you will develope yours for whatever reason.

And I have found only about 20% of posters here see the difference in what they do and other possibilities that might actually be better. Even that percentage may be lower.

 

[Don L]

Far as chafe goes, I have a section of firehose that my snubber line goes through, The hose is long enough so the the snubber rope does not lie against the chain etc.

 

[mvweebles]

There are two main reasons to use a snubber. Add shock absorbancy to an all-chain rode during hi-load situations; and transfer the load from windlass to cleats/bit. I'd venture a guess that 99% of the anchoring by folks on this forum fall into the latter. Why do these threads always emphasize the former?

Peter

 

[chanprr]

Safer in what way?

Backup, planning for the weather, etc, etc?

A single with a plan is just as safe.

Mainstream isnt alway the right path... you will develope yours for whatever reason.

And I have found only about 20% of posters here see the difference in what they do and other possibilities that might actually be better. Even that percentage may be lower.

Well, good question and comments.
Every skipper has a choice. My view while on the water and overnight anchoring in remote places is to be as safe as possible. So I prefer a conventional (two line) bridle, with the separate lines going to a stout shackle. I tie back to a samson post. The setup was tested severely in 25+ kt winds and current on more than one occasion. So in my mind, a bridle is certainly worth the effort.

 

[Simi 60]

The chafe and breakdown is ALWAYS in the same spot on ours, as it point loads over the bow roller.

Our solution is a short 20mm nylon from "real" Sampson post to about a foot behind the roller with dyneema spliced onto that eye.

The eye on the other end big enough to pass those big galv thimbles and rope through allowing us to change out the rope going to chain - short for up to 25 knots and longer length for storm.

This one finished just now before breakfast ready for tomorrows blow.

 

[psneeld]

Well, good question and comments.
Every skipper has a choice. My view while on the water and overnight anchoring in remote places is to be as safe as possible. So I prefer a conventional (two line) bridle, with the separate lines going to a stout shackle. I tie back to a samson post. The setup was tested severely in 25+ kt winds and current on more than one occasion. So in my mind, a bridle is certainly worth the effort.

It's fine that you prefer that method, but there are no facts to back it up that it is "safer".

 

[Simi 60]

Two line bridle no good for us.
Too much chafe and rope actually crosses bow wearing paint.