Docklines: Tight or Loose

[ad_astra]

So this is going to sound like a dumb question.... but which option is best?

In particular, I'm thinking of with respect to storms and wind and such. I'm thinking that tight is the answer, because the looser the lines, the less the line can chafe since it has a smaller possible range of motion (at least with a floating dock where the boat stays at the same height relative to the dock). Yet most pictures of docklines I see, people have them much looser than me. Am I doing something wrong? Or, like with so many other questions on this forum, is there no single right answer?

[Weyalan]

IMO, it depends on whether you are on a fixed or a floating marina. If fixed you need to allow for tide. If loating, not so much. I also think it is important to use a line that is plenty strong, but that does have a decent amount of stretch, which is kinder on the attachement points (both on the dock and, more importantly, on the boat). I I think, if possible, it is good to have the lines loose enough that the boat has a little freedom of movement in the pen, but not enough for any part of the boat to touch any part of the marina

[ad_astra]

But is there any penalty for making it tight if the docks are floating? My boat only has enough slack to move about 6 inches in any direction.....

[dacust]

My thought is that in a storm, the tighter it is, the less room it has to accelerate and snap something. As Weyalan says, stretchy helps, too.

-dan

[sabray]

I snug up the longer spring lines. And leave some play on the others unless they are long leads. Cross the transom lines may help if you think the lead is short. Longer line more stretch. Watch out for chafe points though some boats don't do the transom cross thing well.

[klem]

There are two schools of thought on this, one says leave a lot of slack and one says leave dock lines tight if you are on a floating dock. If you look at how most fishing boats tie up, they tend to tie up pretty loose but they are steel and don't use fenders. The advantage of doing it this way is that the boat tends not to jerk around as much and it often finds an angle that it is happiest to lie to. Leaving slack is a requirement for people tying to fixed objects when storm surge is expected. The difference between a yacht and a fishing boat is that you don't want to leave enough slack that you can rub against the dock.

The other school of thought says keep them as tight as possible. The idea here is that the boat cannot gain momentum and shock load a line. In addition, if you rely on fenders, you can control where you contact.

One thing that is always true is that longer leads are better. This will keep the shock loading in the lines lower. Whether you keep them taut or slack depends on your specific situation and your preferences.

[Dreaming Yachtsman]

I prefer to keep my mooring lines tight to limit the motion of the boat to the minimum. Last year in El Cid Marina in Puerto Moreles, Mexico, (about 20 miles south of Cancun) winds and surge were so strong that even with taught lines, the boat moved around enough to flatten 4 of my fenders. Fortunately, Honda Marine in Cancun had replacements.

This is one of those preferences that seems to be personal, much like what is the best anchor and whether to sail one, two, or three hulls. Perhaps it would be better answered with a poll?

[maxingout]

For me it always depends which line you are talking about. I will keep a spring line taught that keeps my bow off the dock. Other lines are variable in tightness depending on tides when I am at fixed docks. Fenders are just as important as lines because they keep the boat off the dock. I don't skimp on fenders and fenderboards.

I was in a tropical storm in the caribbean, and my westsail 32 pulled the cleats out of the dock. That's a different sort of a problem. I had preplaced a stern anchor which saved the boat from hitting the bulkhead.

I avoid being at the docks in storms. There is too much potential for problems. I would rather be anchored out.

[hummingway]

Snug springs but loose enough on the stern and bow to allow the wave action without jerking the lines. I went through some serious storm action last winter and worked this out in 70 knot winds in the middle of the night. The spring lines and a mid line will prevent the boat movning from the dock as well as ease hobbyhorsing. The bow and stern lines can then prevent any radical pivoting but won't be tight at the top of each rocking motion.

I got this one down so that I was sleeping through gales despite being at the end of a pier where the waves and wind were pretty ferocious.

[Pelagic]

It is a great question ad astra, but as other have said, it depends on your tie up points on a floating dock.

Here in Subic with Typhoon winds happening 3 to 4 times a year I have seen heavy lines and dock cleats let go because the owner left too much slack and the momentum generated by +60knot wind…. just broke things.

The secret is to keep your lines as tight as you can, but also as long as you can.

I have a 70 ft dock on either side of me, so I am able to tie up both sides in such a way that my 38 ton boat is held away from the boarding side and I do not need fenders.

My individual breast lines are actually fairly long, fore and aft, short springs that harness the boat to that side, with some stretch, but still tight. So 8 lines are used for the 4 breast line purpose.

Then 2 long springs each side are kept very tight in Typhoon readiness, so that some give is there, but not enough to set up harmonics with opposing lines.

Then when it looks really nasty, I have very heavy lines that go around the cement pilings.

But this is because we can get extreme weather.

If you are tied to a single dock, as Maxi said, you can use your spring lines to torque yourself off the dock, but if I am tied up to a single dock and expecting a typhoon I have laid out a couple of spare anchors fore and aft to keep the pressure off the fenders.

[Roaring Girl]

If you are experiencing significant movement/shock loads on your fittings then add some springs to your lines. There are lots on the market - eg rubber stretchers you wrap the line around, or big concertina like objects that expand like a bull-roarer. These will seriously protect your fittings, your lines and your sleep.

On tight vs loose it is absolutely a product of place and weather.

[Black Diamond]

The real problem is not the snapping back and forth, but chafe. No matter how well you protect against chafe, you should expect that your lines can chafe thru in a storm. Hurricane Gloria did a number on us in RI a few years back. Most boats didn't break their lines from sheering force or shock loads. It was from hours of constant chafe as the storm raged for hours and hours.

What I usually do (and did during todays' Earl) is have 2 lines set up at each point, one a bit more slack than the other. Should the first chafe thru or break, the second will pick it up and be relatively healthy when it does. It won't have contracted down to half its size from the first 3 hours of storm.

To the original point, on docks I would tend to keep the lines tight, but that's not so much for the line as it is respect for the fact that boats have gotten beamier in the last 10 years and there isn't much room for sloshing around anymore. Two 15' beam boats next to each other makes for one heck of an egg cracking contest.

Rick
S/V Black Diamond
Hylas 49 #057
Portsmouth, RI.

[capngeo]

Another thing to keep in mind when double tying..... Stagger your cleats, as they fail too.

By stagger I mean (for instance) on bow lines I double the lines leaving one slightly slack as mentioned above... BUT instead of going to one cleat, I cross the deck to what would be the leeward cleat in a blow. This way if the windward cleat OR line fails, the bow will still be held.

[Healer52]

Originally Posted by capngeo

Another thing to keep in mind when double tying..... Stagger your cleats, as they fail too.

By stagger I mean (for instance) on bow lines I double the lines leaving one slightly slack as mentioned above... BUT instead of going to one cleat, I cross the deck to what would be the leeward cleat in a blow. This way if the windward cleat OR line fails, the bow will still be held.

Very good idea - I like that better than using extra cleats on the same side....if one failed and did structural damage a nearby cleat may be nonfunctional as well.

[gettinthere]

lines stretch more when wet which happens often when the wind picks up. I'm in a tight slip so I keep the lines tight.