3 point snubber attachment

Take a look at the three point snubber attachment on the Great Harbout N37 in the Yachtworld link below, and the three point bridle plate in the link below that;

2010 Great Harbor N37 Trawler Power Boat For Sale - www.yachtworld.com

Multihull Bridle Plate System - Colligo Marine - Synthetic Rigging

Interesting set up, no? Reminds me of an equalized anchor system from my climbing days, and would help reduce scope for boats with anchor pulpits high above the water. Discuss?

Looks similar to the one I want to build, only I want something a little longer.

Crusty Chief said:

Looks similar to the one I want to build, only I want something a little longer.

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Without knowing for sure and just guestimating the physics involved...wouldn't a three point system allow a shorter snubber because the forces are divided by three?

That 3 shackle plate is what I've seen used to setup 3 anchor mooring systems. For permanent or storm moorings.

For day to day anchoring it looks a bit overly complicated and unnecessary. Plus you always have those two lines hanging off your bow.

I've also wondered if lowering the point of pull of your anchor rode by only 6' or so significantly changes the holding power of your anchor much over a normal snubber setup. I wonder if anybody has done that in an anchor test?

As always YMMV

From everything that I've read and researched, once a strain is on the snubber the attachment point at the chain is supposed to be below the water. Don't think it really effects the scope length, but is supposed to take the strain off the Pulpit.

MurrayM said:

Without knowing for sure and just guestimating the physics involved...wouldn't a three point system allow a shorter snubber because the forces are divided by three?

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With an anchor snubber it's all about stretch. Longer line equals more.

While interesting, I'm not such a great fan of that setup.

First, it creates something load bearing right at the water line.
Second, it creates a situation where I would be worried about that line tied to my bow while under way.

I like the concept of using the two forward cleats as snubber attachment points. That gives me the opportunity to use it when conditions warrant and yes, not all anchoring in my opinion warrants the use of a snubber. It also removes strain from the pulpit, which again when conditions warrant is important.

In practice I do not use a snubber much of the time. If it's calm, there is really not much if any force on the chain and my windlass other than weight. When it gets breezy I deploy the snubber.

ksanders said:

While interesting, I'm not such a great fan of that setup.

First, it creates something load bearing right at the water line.
Second, it creates a situation where I would be worried about that line tied to my bow while under way.

I like the concept of using the two forward cleats as snubber attachment points. That gives me the opportunity to use it when conditions warrant and yes, not all anchoring in my opinion warrants the use of a snubber. It also removes strain from the pulpit, which again when conditions warrant is important.

In practice I do not use a snubber much of the time. If it's calm, there is really not much if any force on the chain and my windlass other than weight. When it gets breezy I deploy the snubber.

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With a snubber attached at the bottom of the bow, how would you cut the anchor loose in an emergency? I can undo a snubber attached at the cleats.

Howard

hmason said:

With a snubber attached at the bottom of the bow, how would you cut the anchor loose in an emergency? ...........
Howard

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A V (two line) snubber is sufficient and simpler when using a chain rode.



(Earlier in the day when wind was stronger, there was more strain on the snubber.)

With a snubber attached at the bottom of the bow, how would you cut the anchor loose in an emergency? I can undo a snubber attached at the cleats.

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Does said emergence involve the windlass being inoperable and the crew for whatever reason not able to raise enough chain manually to dis-engage? That's the only circumstance I can think of offhand where the question is a concern. Pretty remote circumstance. Typically the chain hook is only a couple of feet underwater, so even on a high freeboard boat like the Hatteras, allowing for some angle, you're talking maybe 12 or 15 feet of chain to haul in.

I kind of like the close to the water line set up, because indeed it cuts down on the scope required, in my case by 40 feet +/-, though I never bothered to do the retro fit.
You would sure want to be very certain those eyebolts and the backing plates were very very hefty.

I also think a three point is over kill. A dual works nice; in reality the boat lays to one side of the bridle at a time until things get very sporty.

Is a snubber used on a combination rode? If so how?

I ask because the reason stated for using one in the first place is to take the weight/tension off the pulpit.

CPseudonym said:

Is a snubber used on a combination rode? If so how?

I ask because the reason stated for using one in the first place is to take the weight/tension off the pulpit.

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Yes and No.

More importantly than the pulpit is the windlass.
My first month before i got the 400' chain, I had combo rode.

I took extra slack out of the chain locker and then secure the rode thru the bow hawse pipe and cleat. That way the windlass was not being used as a brake.

Ya, what Richard said. That's what I ment to say.

I guess I am missing something, where is the third point?

CPseudonym said:

Is a snubber used on a combination rode? If so how?

I ask because the reason stated for using one in the first place is to take the weight/tension off the pulpit.

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The purpose of the snubber is to put a bit of elasticity in the rode. If you've got a nylon rode, that's already accomplished. If worried about the strength of the windlass, tie the nylon rode to a secure cleat. More likely to get strong jerks on a chain rode, so a snubber is often desired.

markpierce said:

The purpose of the snubber is to put a bit of elasticity in the rode. If you've got a nylon rode, that's already accomplished. If worried about the strength of the windlass, tie the nylon rode to a secure cleat. More likely to get strong jerks on a chain rode, so a snubber is often desired.

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Exactly right.

In my book, the purpose of the snubber is to take the load off the windlass. It's not designed for jerking, heavy loads in one direction and you will eventually bend the shaft of the windlass with loads like that. Then you get to pull the whole thing in by hand or cut the rode.

I almost forgot, the subject anchor thing is trouble waiting to happen. I can also see the boat hitting something with that through-hull and basically can-opening that hull.

motion30 said:

I guess I am missing something, where is the third point?

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Good point. I was assuming there would be a third line coming from the pulpit, but that isn't necessarily so.

I have a combo rode with 120 ft of chain. In shallow waters, I'm using all chain to anchor and use a Shockles snubber on a nylon line to the cleat to provide elasticity to the rode for shock load reduction and to unload the windlass.

In deeper water, I will deploy 30 or more feet of line rode and secure the line to a cleat on my pulpit to unload my windlass. I'm not worried about my pulpit loads...just don't want the windlass clutch relied upon for anchoring security.

"With an anchor snubber it's all about stretch. Longer line equals more."

TRUE , but the snubber line should never be long enough to reach the prop, should it wander overboard while underway.

Simplest is a 3/8 line with a bowline into a chain link.

Remember the bow eye mounting backing plate must be strong enough to take the breaking strength of the snubber line.

A 4 inch hole at the water line would tax even an engine driven 3 inch pump.

Simplest is a 3/8 line with a bowline into a chain link.

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That's OK for holding the anchor into the roller in lieu of a chain stopper, but incorrect for a snubber for a deployed chain anchor rode. The snubber line should be the same size as what you would use for a rope rode for the boat in question. For a long time I used to just take a 3 strand line of the proper size and attach it to the chain with a rolling hitch; it held very well on numerous occasions when the chain was fully tight for sustained periods of time. I eventually acquired my snubber bridle as a gift from a friend who was getting out of big-boat boating.

Yes I use a snubber. But I've often wondered how many windlasses are damaged by not using one. Is this a red herring topic? The deck mounted drums on the front of most commercial fishing boats are snubber free from my observations. How about the enormous strains imposed on sailing winches?

I anchored for years on the Mississippi with an all rope rode and windlass holding all the current induced strain. Never had an issue. Guess that Trojan woodie was just stouter than our FRP vessels today.

I had a friend that damaged a bow pulpit when they had to anchor in rough seas due to a failed shaft seal. We used to use a chain hook on a nylon line and tie it to the Sampson post to take the load off the windlass. That setup still put pressure on the bow pulpit through the roller. I put together a snubber harness that connects to the bow cleats and takes all the load off the weaker components.
As a side note our pulpit is reinforced with a 1/4" stainless plate. We have 100 feet 3/8 chain and 100 feet rope.

Capt.Bill11 said:

That 3 shackle plate is what I've seen used to setup 3 anchor mooring systems. For permanent or storm moorings.

For day to day anchoring it looks a bit overly complicated and unnecessary. Plus you always have those two lines hanging off your bow.

I've also wondered if lowering the point of pull of your anchor rode by only 6' or so significantly changes the holding power of your anchor much over a normal snubber setup. I wonder if anybody has done that in an anchor test?

As always YMMV

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In theory, lowering the pull point 6' should allow scope to be shortened by 30'. Worthwhile in a crowded anchorage situation. I too worry about being able to "cut free" easily if needed.

I like that idea

sunchaser said:

Yes I use a snubber. But I've often wondered how many windlasses are damaged by not using one. Is this a red herring topic? The deck mounted drums on the front of most commercial fishing boats are snubber free from my observations. How about the enormous strains imposed on sailing winches?

I anchored for years on the Mississippi with an all rope rode and windlass holding all the current induced strain. Never had an issue. Guess that Trojan woodie was just stouter than our FRP vessels today.

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Yes Tom I agree 100% with you on this.

I have a great snubber. Two point attach, shock absorbers, Mantus chain grab. Built it before I actually anchor'd using out all chain rode, at our normal depth of about 100'

Then I noticed that the chain never even gets tight like my nylon rode did. The chain hangs straight down almost all the time.

That tells me that there is in most instances not enough force on the boat to even lift the chain.

So I don't use the snubber much. I break it out in a storm, but day to day anchoring, the snubber isn't needed.

As far as force on my pulpit, well thats's just another case where the often disparaged Bayliner shines. My pulpit isn't just a pulpit, it's a freaking observation platform. Easily room for two, and stout as can be. It looks like a surfboard bolted to my bow, but it's a great place for a deck chair.

sunchaser said:

How about the enormous strains imposed on sailing winches?

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Correct, and the force is at 90 degrees to the winch mount, and they do take jerking strains.

I've run aground with a 36' sail (12,000 lb) and ran my anchor out in tender and winched myself off.

As long as mounting bolts held there was never damage to bearing surfaces within.

Having said that, I did take them apart every year and clean/lube them.

Re Murray's original post ...

I always use the longest and best snubber of all .. a nylon rode.
And I use only anchors that are good short scope performers.

But in addition to a Kellet one could rig a bow eye (kind of like used on small boats) and attach a quick clip to the anchor line and it to the bow eye. That would lower the angle of the rode and definitely enhance short scope performance. And if one was bent on doing this gett'in into the dinghy would work if no other method of attachment could be found. For safety though a way to release the attachment from the deck above would seem necessary.