dock line advice

[CapnRon47]

We bought our first boat and (motor)sailed it from Ct to NC, where it will stay at our second home there. We are down at the house one week every few months so I need to tie the boat off to weather whatever. I have diligent and helpful neighbors, but hey its my boat. I will admit it I am anal as they come (a nearly retired engineer) and the fact is I enjoy thinking about things and figuring out a better way through my effort or others. So I am having fun and looking for advice.

Here is the situation:

our dock faces slight north of east out into the Neuse river. the Neuse is 5 miles wide at this point and flows north into Pamllico sound. I am not trying to weather a hurricane here, there are better places up the creek or out of the water for that. But I would hope it would be safe through other storms. The main issue is water rise and fall from wind tide. As you can see I will only get breaking waves from one rather specific direction. But when the river kicks up the creeks do get waves rippling in. So I have the boat pointed out and a spider work of dock lines.



Under normal (storm) conditions, the water can rise and fall here 3-4 ft. When the wind blows north the bay is pushed north and the water here falls, and vice versa for winds to the south. In a hurricane the water level is probably over the pilings, so this is not the best spot to be. I have bow, stern and spring lines. However, if my lines are tied to the top of pilings, they will be slack when the water is high and if I tie them to base of pilings they are slack when the water is low. So I have done both as shown here with the bow lines.



I have not figured out what to do on the outside pilings yet. I could tie the lines at the same level or perhaps go with one of the arrangments that ride up and down the piling (any comments on their effectiveness and which to get?). On the bow of the boat I have criss crossed the lines as I think this presents less of a sharp angle to the line coming from the cleat.



I could run the line over the rub rail top as I have here for one bow line, but I am not sure I like that arrangement (comments on that?). In any event I need to provide some chafe protection as I noticed some wear on the brand new (black) 3 strand nylon lines for the bow over the past 4 weeks. So I recently added what came with the boat to the side that is showing the wear. I need to do something about chafe and I read that poly line wears better for chafe and I am thinking of making some short sections of poly line that will go from the cleat through the chock and then tie off to the nylon line. Has anyone tried this or have any comment on what works best for chafe through these chocks?

So there are a few specific questions and a general request for advice or comments on what others might suggest.

[erps]

Does the dock float, or is it fixed to the pilings? If it floats, it would simplify dealing with the varying water levels (at least on one side) by fixing cleats to the dock. Pretty boat. Is it a C&C?

[CapnRon47]

Ray,
The dock is not floating. It is concrete dock attached to pilings and is meant not to float so that the pilings do not get beat up during storms.

The boat was built by Holby Marine in 1990, its their Clearwater model and has a swing keel, which I need for the aforementioned rise and fall of water level in the creek.

thanks,
Ron

[sailingdog]

Given the tidal range you're talking about, it would probably be wise to cross the stern lines. That will help keep the boat centered yet allow it to move up and down with the tides better. Using longer docklines, like leading the aft spring line to the aft cleat, rather than to a mid-ships cleat will help with the boat in coping with the tidal range.

IMHO, you should be tying the docklines a bit above center...not at the top or bottom of the range. If you tie to the top, you have to have more slack to make sure you can go all the way down.. if you tie at the bottom, you have to have more slack to make sure you can go all the way up... tying in the middle or just a bit above it will minimize the amount of slack you need to put in the lines.

You should also be using synthetic chafe protection sleeves. They're made by a bunch of different companies. Some are designed to slip over the end of the line and tie into place, others will open via a velcro flap and then can be put over the line and tied into place using a thin cord. The ones I have are by Taylor Made.

Rubber or plastic hose and leather wraps make lousy chafe guards since one thing they've found on nylon dock lines is that a majority of the failures aren't due to chafe, but due to the line failing from overheating due to internal friction, and leather, rubber or plastic chafe guards hasten this process by preventing water from getting to the rope and lubricating and cooling it. The synthetic chafe guards I mention allow the rope to get wet and cool down quite a bit better.

For a storm, it might also be wise to put out anchors fore and aft...to help keep the boat from moving in the case the docklines fail.

BTW, it was pretty obvious that the docks don't float, since two of the bolts holding it to the pilings are clearly visible in the second photo.

One other thing... don't attach lines like the white one going over the port toe rail to the cleats that way... cleats are strongest when the angle between the line and the axis of the cleat is almost parallel, and weakest when the lines are perpendicular to the cleat. If that line were to become heavily loaded during a storm, it would probably have a good chance of ripping the cleat out of the deck—as it has far more leverage than the black dockline attached to that same cleat.

[sailingfool]

Tie the bow and stern lines to the height suitable for mid-tide on the pilings, with the length so that at mid-tide the bow and stern cannnot quite touch the pilings on either side. That eatra length will allow for the rise and fall.

Ditto arrangement for fore and aft spring lines.

At dead low the boat should be in the middle of the slip space with a little slack left in all lines (ignoring effect of wind and tide) to allow for spring tides.

Your dock lines don't look large enough, hard to say your boat size ( an a nice looking craft it is...) perhpas similar to my 36, for which I believe I have 3/4" or so nylon. Run all lines subject to chafe through 2 foot sections of plastic hose for protection. I avoid using lines with a fixed loop in the end, as they will chafe at the same point, if you come down in a blow and see serious chafe, you have to replace the line versus just making an adjutment.

3-4 feet should be no problem, in Maine it can drop 10-12...

[Delirious]

Your set-up looks pretty darned good. I'd add two things. Our local fire departments perodically toss their hoses. We've begged often enouth that they now drop them off at the marina. You might want to ask yours for the cast-off hoses. They are a thick rubber lined hard woven covering material that makes GREAT chafe coverings for pilings. Lacking that I'd add bought anti-chafe cobverings.

I'd also row the anchor out ahead of the boat 10X the depth and set it (with a float to alert your neighbors) as you're facing the weather. That could help a bunch.

[CapnRon47]

All,
thanks for the responses. I will look into making some of the suggested changes.

the boat came with an assortment of lines, some of which I need to replace. I purchased the two new 1/2" three strand nylon dock lines our last trip, with the thought of doubling up the lines rather than going with 3/4", but I suspect you are right in that if one 1/2 line breaks under load then the other one is likely to break also. Better to go with a higher load line.

I have the fwd spring lines running to the bow cleats , but I also ran them through the outside rollers to keep them in place, so thats why they look like they go to the midship cleat (which I don't have). the aft spring lines run throught the inside rollers to the winches in the cockpit. I did not want the spring lines to end up against a lifeline stanchion so I thought going through the rollers for the jib sheets would be a better arrangement?

I would like to cross the stern lines but the lines rub on the swim ladder and I have not found a position for them to prevent that. Perhaps I should just put the ladder down.

If I tie to the mid piling point I suspect that means I need to add cleats to the pilings to keep the lines from possible slipping down. Or should I expect a 3-4 clove hitchs to stay in place.

[CapnRon47]

forgot to say that it is a 35 footer.

[sailingdog]

You might want to tie a round turn and two half hitches instead. Clove hitches have a nasty tendency of loosening unless under a constant load IMHO. It'll also be faster to untie or tie a round turn and two half-hitches than a series of clove hitches. Finally, have you ever tried to untie a clove hitch when it was under a load—you generally can't. You can pretty much untie a round-turn and two half hitches almost any time at all.

I use 1/2" lines on my boat...and it's a lot smaller and lighter than yours... Go with 3/4" lines. You'll sleep better.

BTW, I wouldn't use the winches to tie the docklines off to. I've seen docklines rip the winches out of the cabintop, or in one case, rip the entire port-side coaming from the boat. Often, they're not really designed to take loads in directions other than what the sheets would apply to them.