What is this and what do I use it for?

[Muaddib1116]

I bought my boat from a European who was in a hurry to get back to Europe, so he left the boat with a TON of stuff in it, which is great, but there's so much stuff that I'm trying to go through and organize. I just found these and I'm not really sure what they're for or how to use them. I assume it's some sort of setup for relieving shock loads on docklines in rough weather? There are two lengths of chain, probably 7/16" (I didn't measure) and the two large springs, and two ~15' lengths of 1" 3 strand, and a few shackles. All the hardware looks to be 316 SS. The two lengths of line seem a little short for docklines, especially for 1" 3 strand. I was thinking maybe the chain is supposed to go around a industrial style dock bollard?

[Olly75]

Yes seen a similar set up for docklines. They are used once you are docked, I'm guessing that somewhere on the boat will be a set of longer lines to get used for the actual docking procedure . I've not seen them used with chains, probably be very noisy when wrapped round a bollard or through a cleat.

You don't want to be trying to set those up until you are stable, or come to that, throw them to someone on the dock as you are coming in!

[Muaddib1116]

Haha, yeah, they are pretty big and hefty. Are these just a heavier duty version of those rubber dockline snubbers?

[wayne.b]

Originally Posted by Muaddib1116

Haha, yeah, they are pretty big and hefty. Are these just a heavier duty version of those rubber dockline snubbers?

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That would be my guess. That kind of arrangement is common in marinas that are exposed to ocean swells. Typically the chain will go around the dock cleat and over the edge of the dock to prevent chafe. One end of the spring is attached to the chain, dock lines to the other end leading to the boat.

[Dogscout]

Chains go around the cleats on the pontoon (dock) then the springs, then the lines to your stern cleats.

Very common with stern to mooring. Aka med mooring

[Muaddib1116]

Thanks, that makes sense, since the boat spent most of it's life in the Med, and this was buried at the bottom of the lazarette.

[Noisykate]

Yes, dock lines for surge conditions. We have the same. Chain round the cleat (not noisy). Reduces squeak at fairleads, and reduces shocks on lines. We still moor up using ordinary (lighter!) Lines, and swap the heavy lines in if we need them.

[meirriba]

See attached sample.
Chain is a safety measure for the spring (if spring fails).
On the picture there are two chains on each spring ad I made the chains initially too long and than added shorter pieces but left the other chains connected.
If you use a chain as the loop over a bollard/cleat you may want to protect the bollard against chafe by covering chain with a plastic or heavy duty cloth pipe, it will also eliminate noise.

[Peter1949]

Great picture of the set up

[sepharad]

I first saw and experienced them in Fethiye Turkey. They worked brilliantly

[Clivevon]

As Meirriba says. This is exactly how I had my boat set up in Mallorca. Good scheme if you are leaving boat unattended for any length of time. NB: safety chains on springs as shown.

[Muaddib1116]

Thanks for the responses guys. Now that I know how it's used, I'm still a little unsure of why it's used. I have zero experience with this type of docking/mooring. My understanding is that there is a bow mooring pendant, or they use a bow anchor, and the boat is tensioned between that and the dock at the stern. Is the spring setup so that you can maintain good tension with the bow line, while still allowing for the tide? I noticed that there are two additional stern lines that cross the stern, but those are slack and not setup with springs. Why not just have taut stern lines, if on a floating dock. Even on a fixed dock, I don't see how those springs have enough travel to allow for the tide.

[Clivevon]

This gear is used in the Mediterranean - there is no tide. Sea level changes due to air pressure differences but that tends usually to be just a foot or two - no problem. The docks are solid concrete - not floating pontoons. You moor stern to, close(ish) to the dock so you can get on & off the boat easily, but hopefully the bowline tension means the boat cannot hit the dock. Rig fenders anyway. The springs are there for unattended long term stays (maybe you are back at work) to cushion snatching due to whatever - strong winds, thoughtless traffic, surges from earthquakes far away (happened to me, I kid you not). Normally the bow is secured via a line to a heavy ground chain running down the middle of the marina aisle (the line is picked up by a "lazyline" attached to the dock). The crossed stern lines are an extra precaution to help stabilise the boat within its chosen mooring bollards (strong side winds & less careful boat owners can mean the whole line of boats is pushed sideways).

[Muaddib1116]

Thanks, that's a great explanation. I'll hold onto them in case I ever make it to Europe.

[Mike Banks]

Yes. The chain goes around the bollard, the springs go to the chain, and the rope goes to your mooring cleats.

They are only used for marina type moorings though--or maybe in a river. With ocean tides you need very long bow, stern and long crossed springers.