What size for snubber?

[Jim Cate]

G'Day all,

Here's an anecdote re putting the anchoring loads onto the windlass.

We were anchored in Skeleton Bay (NE Tasmania) in about 15 metres when we had an unforecast shift from S'ly quadrant to NW, rising quickly to about 25 knots. The boat did a big swing through around 180 degrees, and in the process fouled the chain (10 mm G-3) on a big rock with nearly 1:1 scope. A short choppy sea quickly rose, and very soon our 14 mm octoplait nylon snubber parted (loudly!). The bang was followed by a peculiar whining noise that I couldn't identify. Investigation revealed that it was the windlass being driven backwards by the chain load. I wouldn't have believed it possible since it involves a 56:1 worm drive, but there it was...

We soon discovered that the chain was jammed badly and that we couldn't free it in the extant conditions, so we veered a lot more chain, rigged a new snubber and worried all night. By morning it was calmer and I had a dive to free the chain...NOT! It was inextricably jammed. Recovered the anchor and as much of the chain as I could, left the rest for the fish to admire.

I was pleased to find that despite this gross abuse, the Maxwell 1200 was not damaged, and continued to operate for several more years before dissimilar metal corrosion killed it.

So, I'd say that the windlass manufacturers warnings are a bit overblown... but as always, YMMV.

Cheers,

Jim

PS I now use 16 mm double braid nylon for my snubber...

[gettinthere]

I have a very long, crowded bow pulpit. That makes tieing a line to chain difficult. I have a bridle snubber with a chain hook in the middle. Bridle runs thru hause holes to a pair of cleats. It all works well, except for the chain hook. It keeps falling off. So I'm looking for recommendations for a better chain hook.

[tonytheboat]

If your not worried about looks try wraping your chain around a small used tyre and dump that over the side it stop the chain snapping at the load and wneh its shot just go out and get another tony

[noelex 77]

There is a lot disagreement about the actual loads anchoring imposes on the rode. The ideal snubber has quite a lot of stretch, so getting something reasonably thin is better.
However, I am currently using an 18mm nylon snubber on a 47 foot monohull.

This is thicker than I would like and I am not sure it has enough stretch, but I have found that anything thinner snaps in stronger conditions even when well protected from chafe.

Thinner snubbers break with a tremendous bang and its no fun struggling on deck in 50k trying to attach a new snubber.

I think I will try one of the rubber snatch springs on the snubber for the winter gales.

[Hudson Force]

Originally Posted by gettinthere

............ So I'm looking for recommendations for a better chain hook.

I like this chain hook with the U-shape that allows me to swing it out under my chain and secure an attachment to a link then belay the two snubber lines on my port & starboard bow cleats. After deploying a few feet of additional chain that dips from my hook and back to my bow roller, I never have had the hook disengage. When I take in my chain the hook falls from the chain and is lifted on board with the snubber lines. You'll see the manufacturers stamp "ABI" on the enlarged photo.

[s/vPainkiller]

Originally Posted by cfarrar

Scott,

I also use a chain/rope combo (100' chain). In order to protect the nylon rode where it passes over the anchor roller, I often use a snubber: a dyneema strop on the rode with a kleimheist, then the snubber attached to the strop. Cleat the snubber and the rode. If it's a well-protected anchorage I sometimes just cleat the nylon rode and use some velcro-style chafe gear at the anchor roller, just in case.

Basic questions: what size dyneema do you use for the strop, and what is the knot that makes the loop? Also, how then do you attach the snubber line to the dyneema strop, bowline or some other special-purpose knot? I looked up the klemheist and prussic knots, so I see how they are used. Thanks.

Scott

[noelex 77]

Originally Posted by s/vPainkiller

Basic questions: what size dyneema do you use for the strop, and what is the knot that makes the loop? Also, how then do you attach the snubber line to the dyneema strop, bowline or some other special-purpose knot? I looked up the klemheist and prussic knots, so I see how they are used. Thanks.

Scott

If you want to use a chain hook this looks like a good one.
Mantus Chain Hook | MantusAnchors

Personally I use a Klemheist knot with a short spectra line. This has no stretch but it attached to to the long nylon snubber which provides the stretch.

Very quick to tie and reliable with no slip. It also does not risk chipping the galvanising off the chain.

Spectra is stronger than nylon (but no stretch) and it is doubled which helps distibute the load. The thinner the line the easier it is to tie. I think mine is 15mm and aout 1m long, it has never broken.
It is attached to the snubber with a shackle.

[cfarrar]

The cheapest solution is to attach your nylon snubber with a kleimheist or prussic directly to the chain or nylon rode. Still, it's easier to tie the hitch with a shorter piece of smaller diameter line. We've got 4-5 ft of 9mm Dyneema with a eye spliced into both ends (brummel lockstitch). This goes onto the chain or nylon rode with a kleimheist. Our nylon snubber is spliced to a Wichard #2328 asymetric snap hook. This hooks through both eyes of the Dyneema, using a single snubber, or we can use two snubbers, on hooked onto each side of the Dyneema, to create a bridle. The Wichard hook can also attach to a chain hook or a mooring eye. The Wichard hook and Dyneema both have large WLLs, and the dyneema is very chafe resistant. In the end I think the weak point in the whole system is snubber chafe at the anchor roller or chalks. Note: I plagiarized this setup from a CF member - maybe SailFastTri?

[cfarrar]

Last year I got one of these chain hooks to try out, for $20 at Pride Marine in Canada, recommended by a CF member:
http://www.marineoutfitters.ca/index...e=773692282664
It puts a symmetrical load on the chain, instead of twisting it. It stays on pretty well, yet when you're hoisting anchor it kicks itself off as it passes over the anchor roller. The large bail allows you to splice one or two lines, or attach a snap hook. I don't know about the WLL might be, and in the end I'm sure my Dyneema / kleimheist is stronger.

[rebel heart]

I have a 3/4" snubber (5/16" chain, ~25k pounds of boat, 8 in the keel).

I know it's a little oversized, but here's my deal with it:

- With a bowsprit, I run a block off the crans iron at the end of the sprit. The snubber goes through the block, with one end rolling hitched to the chain and the other back to the samson post.

- On this boat I haven't seen a ton of wind at anchor (happily), certainly not enough to remove the catenary from hundreds of feet of chain.

- The snubber is primarily to safeguard electric winches, not manual. I have a manual with a stout locking latch, much bigger than most chain stoppers I see on production boats. I put the sprit and windlass on the boat (after removing completely and repairing), so I'm fine with load.

- By the time you've straighened out ~200' of chain, you're going to want a strong ass snubber. Skinny snubbers seem weird to me, unless you're doing reduced scope stuff for some really good reason (those reasons do exist in reality).

[rebel heart]

Having a few various 50' lengths of three strand in the 5/16, 1/2, and 3/4 categories seem like a good way to solve this little problem.

[gunnado]

I have been thinking about this for a while and would like to replace my 3 meter 3 strand nylon with chain hook snubber, its never let me down (only have to replace the pvc hose at boat contact point), but i have not had to deal with any extreme conditions in the past year on the anchor. I have a few questions in what to watch out for with the use termination of different materials before trying to make the ultimate snubber? it sounds like noelex 77 has already done it!

my plan and questions

starting at the two bow cleats using spectra static line coming from both cleats with pvc hose coverings for chafe protection where it leaves chain plate or bow roller.
would this eliminate chafing at the boat contact points?

Join the 2 spectra lines from cleats to a 3 strand nylon using splices on a shackle above the waterline.
How strong is this connection any problems here?

Use klemheist knot to join 3 strand nylon to anchor chain or rode depending on the amount of scope i need to let out (FYI i have 50 meters of chain spliced 75 meters of rode on a 60 pound manson supreme on a beneteau 39ft boat).
would the nylon snubber chafe at the klemheist knot on the chain?
would the Klemheist knot chafe the 3 strand nylon rode if i let out all the e chain for longer scope?

Breaking loads and sizes of materials i buy will be slightly stronger than my current chain and rode TBA. Dont hold back if you have already done the math?

ease of use once built? if its not convenient to use then the project is dead and i will keep the snubber i have and wait to hear what they sound like when they break!

[cfarrar]

Gunnado:

The reasons I (and Noelex, I'm guessing) use a short length of spectra or dynemma for the keimheist at the rode, instead of attaching the nylon snubber directly: 1) it's easier to make the hitch if you don't have to pass a long length of nylon through itself, 2) it's easier to hitch small diameter line to a rode, and 3) the spectra / dyneema is chafe resistant, which helps on the galvanized chain. No, the dyneema/spectra will not chafe the nylon rode if attached with a kleimheist, because once it's under load it grips like steel and there's no movement.

If you use a shackle for the nylon-to-spectra/dyneema connection that you describe, watch for chafe. A galvanized shackle would be a problem. If stainless, this could be the weak link in your system. That's one of the reasons I went with the Wichard stainless hooks (3970lb WLL). Plus it's faster than connecting a shackle.

With the system you describe will you be able to adjust the length of your snubber once you attach it to the rode? One of the nice things about a long snubber is being able to ease out another 15-20 ft when you feel like it, or shorten back up, with no hassle.

[gunnado]

fixed length snubber, set and forget, because my boat lives on the anchor and you never know what condition will pop up, or if i will be on the boat when it happens

[noelex 77]

Originally Posted by cfarrar

Gunnado:

The reasons I (and Noelex, I'm guessing) use a short length of spectra or dynemma for the keimheist at the rode, instead of attaching the nylon snubber directly: 1) it's easier to make the hitch if you don't have to pass a long length of nylon through itself, 2) it's easier to hitch small diameter line to a rode, and 3) the spectra / dyneema is chafe resistant, which helps on the galvanized chain. No, the dyneema/spectra will not chafe the nylon rode if attached with a kleimheist, because once it's under load it grips like steel and there's no movement.

If you use a shackle for the nylon-to-spectra/dyneema connection that you describe, watch for chafe. A galvanized shackle would be a problem. If stainless, this could be the weak link in your system. That's one of the reasons I went with the Wichard stainless hooks (3970lb WLL). Plus it's faster than connecting a shackle.

With the system you describe will you be able to adjust the length of your snubber once you attach it to the rode? One of the nice things about a long snubber is being able to ease out another 15-20 ft when you feel like it, or shorten back up, with no hassle.

Most of these comments are spot on.
The shackle between the snubber and the spectra loop can be large so it is not the weak link in the system.

To be effective the snubber needs to be long enough to stretch.
With an increase in wind strength often it is sensible to veer a substantial increase in scope. Generally it is an advantage to extend the length of the snubber in these circumstances.
Having another 20m of nylon line to extend the snubber saves starting the engine and reducing the scope to re-tie the snubber