Dyneema sleeve to protect the snubber

[Sojourn2]

I agree 100% with Dockhead.
There should be no chaff on a snubbed.
Very large U bolt through the stem with a decent backing plate is the best attachment point for a snubbed. Leave it attached to the U bolt and either use a rolling hitch or special chain shackle to attach to the chain.

All sorted.

[waterman46]

Not exactly to your subject, but you mentioned having difficulty setting a long snubber that required acrobatics over the bow. I use the chain hook to attach the snubber line just forward of the bow roller. No acrobatics. Pull firmly on snubber line and attach it to a bow cleat. Slack out on anchor chain a few feet more than desired snubber length, say 12' or so. Now all anchor tension is on short snubber, so carefully ease out snubber line by keeping a turn on the cleat as you do it, letting out about 10' in this example.

[gauvins]

Originally Posted by Dockhead

But I'm curious -- why are you doing this before setting the anchor? The snubber attenuates the connection to the boat and makes it much harder to feel how the anchor is setting.

We have a Rocna (quick set as you certainly know). On all chain. Typically we drop 3:1, secure the chain to our Samson post on 1M of rope to relieve the windlass. Engine in reverse mid to full throttle depending on the circumstances. (Mostly mid). The anchor sets. We wait a bit until the boat gets into position. Then release more chain. Up to 5:1 or so.

Typically we keep track using our chart plotter. If the boat makes forward progress when the engine goes into neutral, it means that the anchor was properly set. No feeling involved.

For now, we free the rope from the Samson while releasing more chain. Then reattach such that eventual surges will not impact the windlass. (We do not have a proper chain stopper).

The plan is (in a few days) to let go of a snubber while we add 10M of chain. Normally in shallow waters, we wouldn't have to change the point where the snubber is secured to the chain.

Do I make sense?

---

Maybe more context. We've spent nights with high winds (50kn) with no problem whatsoever. But now, unusual circumstances have us anchored in a bay where occasionally there will be 1M+ swell and no real alternative - we have to endure. It doesn't last more than a day and if it were to become barely tenable we could always go to the nearest port.

[fxykty]

Originally Posted by gauvins

We have a Rocna (quick set as you certainly know). On all chain. Typically we drop 3:1, secure the chain to our Samson post on 1M of rope to relieve the windlass. Engine in reverse mid to full throttle depending on the circumstances. (Mostly mid). The anchor sets. We wait a bit until the boat gets into position. Then release more chain. Up to 5:1 or so.



Typically we keep track using our chart plotter. If the boat makes forward progress when the engine goes into neutral, it means that the anchor was properly set. No feeling involved.



For now, we free the rope from the Samson while releasing more chain. Then reattach such that eventual surges will not impact the windlass. (We do not have a proper chain stopper).



The plan is (in a few days) to let go of a snubber while we add 10M of chain. Normally in shallow waters, we wouldn't have to change the point where the snubber is secured to the chain.



Do I make sense?



---



Maybe more context. We've spent nights with high winds (50kn) with no problem whatsoever. But now, unusual circumstances have us anchored in a bay where occasionally there will be 1M+ swell and no real alternative - we have to endure. It doesn't last more than a day and if it were to become barely tenable we could always go to the nearest port.

Here's a few ideas that may help you.

Lengthen your snubber and decrease the diameter. You want the snubber to stretch to relieve the shock loads of waves, and to do that you need length and stretchiness. Length not less than 5m and preferably 10-15m. Reduce the diameter as much as possible based on the rope's working load limit so it's about 30% less than the breaking strength of your chain.

Secure the snubber to an aft cleat or winch and lead it forward (using fair leads or LFRs as needed) to your bow roller (a second roller that doesn't have the chain on it is nice, but not necessary). The snubber should be connected to the chain beyond the bow roller, but not too far and certainly not so far that it can drag on the bottom. Securing the snubber aft gives you lots of length and without having the snubber attachment way in front of the boat. This helps in shallow anchorages but also if you ever need to let more scope out - you only have to bring in a little amount of chain to get to the snubber attachment point, release the snubber, then ease more chain for the new scope.

When anchoring, set at 3:1 or whatever (and continue to use a short, strong length of line as a chain stopper, or just engage the winch brake), then once set let out your chain to the desired scope. Attach the snubber to the chain using a rolling hitch, icicle hitch, or dyneema soft shackle at some point between the winch and the bow roller, then let enough chain out so that the snubber takes the load and you have enough chain looped so it doesn't come tight as the snubber lengthens.

Regarding knowing whether the anchor is setting properly you need to be on the bow and feeling the chain. If it bounces or jerks or scrapes then your anchor is moving. If the chain becomes still and quiet and the boat stops reversing then it's probably set (if the boat keeps reversing on a quiet chain then you're probably dragging through sand or mud and the anchor might be fouled - lift it up to check).

Hope this helps.

[Dockhead]

Originally Posted by gauvins

We have a Rocna (quick set as you certainly know). On all chain. Typically we drop 3:1, secure the chain to our Samson post on 1M of rope to relieve the windlass. Engine in reverse mid to full throttle depending on the circumstances. (Mostly mid). The anchor sets. We wait a bit until the boat gets into position. Then release more chain. Up to 5:1 or so.

Typically we keep track using our chart plotter. If the boat makes forward progress when the engine goes into neutral, it means that the anchor was properly set. No feeling involved.

For now, we free the rope from the Samson while releasing more chain. Then reattach such that eventual surges will not impact the windlass. (We do not have a proper chain stopper).

The plan is (in a few days) to let go of a snubber while we add 10M of chain. Normally in shallow waters, we wouldn't have to change the point where the snubber is secured to the chain.

Do I make sense?

---

Maybe more context. We've spent nights with high winds (50kn) with no problem whatsoever. But now, unusual circumstances have us anchored in a bay where occasionally there will be 1M+ swell and no real alternative - we have to endure. It doesn't last more than a day and if it were to become barely tenable we could always go to the nearest port.

OK, that makes perfect sense. Sorry for jumping to the wrong conclusions and being a pedant.



I envy you your samson post. I would give a lot for one of those. Few modern boats, unfortunately have them.

[gauvins]

Thanks for your suggestions.

A couple of posts suggest tying the snubber to (u-bolt/winch/cleat set amidship or further back). While it may work on some boats, it will not in our case. The bow rollers are mounted on two half-inch thick stainless plates designed to contain lateral motion (including a 3/4 inch rod to secure the anchor when we're under way, or the chain when at anchor. (Which is excellent, btw).

Now, this setup makes it impractical to send the snubber behind the windlass. It would chafe on the steel plates, or require blocks and whatnot to avoid them.

At the minimum, we can drop 8M of snubber (2 on deck, 2 to the water surface, 4 under the waterline). That will do.

[gauvins]

Originally Posted by Dockhead

OK, that makes perfect sense. Sorry for jumping to the wrong conclusions.



I envy you your samson post. I would give a lot for one of those. Few modern boats, unfortunately have them.

Nothing to be sorry about.

Wrt Samson post - yes, great. And right, we're talking 30 year-old steel boat. If you really really really want a Samson and currently own an almost new boat, feel free to PM me so we can discuss a swap

[Cpt Mark]

I envy you your samson post. I would give a lot for one of those. Few modern boats, unfortunately have them.[/QUOTE]

Might look a bit weird but you could add one if you like.

[thinwater]

Not so fast on the rolling hitch.


Testing shows that a rolling hitch, like any knot, is only about 58% of the rope strength... when it does not slip. Thus, it is not like a splice.



Testing shows that it slips ~ 80-90% of the time at about 17-20% of the rope breaking strength. In fact, there are reports from a number of well-know world cruisers of rolling hitches slipping (no name dropping) and they have gone to either soft shackles, two rolling hitches, or prusik hitches. Many cruisers can go a lifetime without noticing this, since this will only happen in gale conditions. That data says they slip at high load, the result of line shrinkage and the chain links moving.


Personally, I like either a soft shackle or prusik. Both can be strong as the chain if made from Dyneema.

[gauvins]

Thank for the data. Interestingly, I was also considering the Prusik (could be faster/easier to set compared to a soft shackle)

[conachair]

Originally Posted by gauvins

Thank for the data. Interestingly, I was also considering the Prusik (could be faster/easier to set compared to a soft shackle)

I actually find a big long soft shackle easier, might be worth trying both methods.

[thinwater]

Originally Posted by conachair

I actually find a big long soft shackle easier, might be worth trying both methods.

An extra long soft shackle is a help.

[gauvins]

Yes... I made a shackle out of lifelines leftovers. Longer than standard but not long enough to run a Prusik over the chain. On a dead calm, by day, when there's nothing to do but consider things like these, yup, pretty easy to thread. (I've added a string of a couple of inches that I can grab to pull the shackle's small end through the chain. Does help)

[waterman46]

Can anyone tell me why so many of you seem to use complicated and possibly slippery knots instead of the simple chain hook? Don't tell me the hook will slip off, of course it will, if tension is not kept on the snubber. Never been a problem as far as I can remember.

[gauvins]

Maybe reading the OP would help...