Association Forum - Dockline Thickness

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

General Sailing Forum

Dockline Thickness

New Topic

Topic Locked

Printer Friendly

Author

Topic

Page: of 2

cat1951
Admiral

Member Avatar

USA
636 Posts

Initially Posted - 02/08/2007 : 13:44:42

I have a 1985 C25 sr/fk and am planning to get new docklines. Our arrangement is that we have a dock finger on each side, so springlines are not necessary, or at least we do not use them. We have each of the port and starboard sides tied down forward and aft. The question that I have is how thick the lines should be. 3/8", 1/2", or 5/8". We are on a lake in a very protected cove, so we do not have direct exposure to wind, waves, or tide levels.

Mike
Grand Lake, OK
N.O. Catalina 25 #4849
In my opinion 75% of the earth is water for a reason. That's why I sail.

Edited by - on

dlucier
Master Marine Consultant

Members Avatar

Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 02/08/2007 : 13:59:56

Inland lake, protected harbor, no tides...I'd use 3/8" line. If you like bigger, you can go to 7/16", but 1/2" might be a bit much.

Edited by - on

Heartbeat
Navigator

Members Avatar

USA
161 Posts

Response Posted - 02/08/2007 : 14:23:36

I am of two minds on dock line thickness.

First is the cheap approach: 3/8" twisted. Affordable, easy, light, and functional.

Second is the overkill approach. When I lived in Tampa, my club (Tampa Sailing Squadron) required two 1/2" lines (and chafe protection) from each of the four corners (total of 8) of the slip to the boat during Hurricane season. The setup (I still use it here in Detorit) works very well, and I have solid piece of mind in case of a storm.

Determine what you are willing to spend, and go with it. 3/8" will definately hold the boat.

Matt Q.

Edited by - on

Justin
Admiral

Members Avatar

502 Posts

Response Posted - 02/08/2007 : 14:24:06

I was wondering this exact same question because I got the email from West Marine about their Rope Sale. Lots of lines on sale at what look like nice prices through the weekend. Maybe this should go in a separate thread, but what is the recommended nylon anchor rode thickness? I might buy some new docklines and anchor rode.

Thanks,

Edited by - on

Nautiduck
Master Marine Consultant

Members Avatar

USA
3704 Posts

Response Posted - 02/08/2007 : 14:24:27

Since we intend to use our boat cruising as well as in the lake we went with 5/8". West Marine is having a good anchor and dock line sale right now. I just bought a 300' anchor rode (1/2") and several of the 5/8" dock lines.

Bruce anchors recommends 3/8 rode for a 25-30 foot boat. I always go up one size.

Edited by - Nautiduck on 02/08/2007 14:26:06

cat1951
Admiral

Members Avatar

USA
636 Posts

Response Posted - 02/08/2007 : 14:39:33

Looks like I am not the only one that saw the WM sale. We have new docklines on the stern, but need two for the bow. I think the 3/8" will be sufficient here in OK, but wanted other opinions. If the marina/cove gets hit by a tornado, we will have more problems than just docklines to deal with.

Edited by - cat1951 on 02/08/2007 14:40:05

ilnadi
Captain

Members Avatar

452 Posts

Response Posted - 02/08/2007 : 14:47:03

We got smaller lines so they are easier to use. We own about 2.5 sets with the extra 1.5 in a bucket for when we cruise. When hurricanes come through, we break out the bucket and tie everything on. That way you don't leave everything in the sun and salt.

Edited by - on

Frank Hopper
Past Commodore

Members Avatar

Pitcairn Island
6776 Posts

Response Posted - 02/08/2007 : 14:59:26

I use 4 25' 1/2" Goldenbraid and cross them fore and aft.

Edited by - on

dlucier
Master Marine Consultant

Members Avatar

Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 02/08/2007 : 15:08:12

From the West Advisor...

Dock Lines

Diameter

We recommend 1/8" of line diameter for every 9' of boat length. Larger lines will wear longer but stretch less.

Boat Length Dock Line Dia.

Up to 27' - 3/8"
28'-31' - 7/16"
32'-36' - 1/2"
37'-45' - 5/8"
46'-54' - 3/4"

Edited by - on

Leon Sisson
Master Marine Consultant

Members Avatar

USA
1893 Posts

Response Posted - 02/08/2007 : 15:57:36

For C-25 dock lines, I use four 3/8" nylon double braid. My boat is tied one side only (outside of dock) in a medium exposed location, less than 200' from the mouth of a canal which is exposed to maybe 5 mile NNW fetch across open water. (My canal is in the SE corner of the open water, so wave action is 'funneled' towards my dock.) My dock lines last 5 to 10 years. I also carry a complete spare set aboard, protected from the weather. For anchor rode I use one each 3/8" and 7/16" nylon double braid, each with about a boat length of chain.

When selecting dockline and anchor rode, bigger is not always better. These lines need to stretch in order to do their job. Too large a line will transfer more shock load to cleats, anchor, and dock. I also use rubber snubbers on all four docklines at my home dock. These may seem expensive if you haven't tried them, but the reduction in shock load is well worth the price to me.

-- Leon Sisson

Edited by - on

At Ease
Admiral

Members Avatar

672 Posts

Response Posted - 02/08/2007 : 17:36:11

3/8" is perfect for a C25/250.

Edited by - on

Nautiduck
Master Marine Consultant

Members Avatar

USA
3704 Posts

Response Posted - 02/08/2007 : 17:52:59

I use rubber snubbers to provide the shock absorbing. Our club requires them.

Edited by - Nautiduck on 02/08/2007 17:53:22

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 02/08/2007 : 19:57:28

We have a huge surge problem in our basin which recommends an extra 1/8th over the norm We go with 9 lines on the boat all 1/2 inch. One on each corner doubled up and one spring line. Doubled up lines allow for someone to snug them up without untying the boat. Something that the yard or a passerby might do if the boat is a little loose in a good blow. The fifth line is to pull the boat in or let it out from the dock as we don't use fenders.

I don't recommend the snubbers, if the snubber breaks, you now have a dockline that is too long for the situation. Plus they cause undo wear in the wrong portion of the line. Docklines have more than enough give.

Edited by - Champipple on 02/08/2007 19:58:54

Dave Bristle
Master Marine Consultant

Members Avatar

Djibouti
10005 Posts

Response Posted - 02/08/2007 : 21:51:39

Well, to add to the opinions, here are mine, for what they're worth (roughly what you're paying for them)...

1/2" is a little big for a 25-footer, and 5/8" is way too big--in part because of stretch and in part because it doesn't fit securely on the rather small cleats on the C-25. The loop should be crossed over or run through the cleat--not just laid over it. Double-braid stretches considerably less than twisted nylon--therefore nylon is the preferred anchor rode used by most cruisers for its shock absorbtion, which is important for keeping an anchor set in a blow. 1/2" is plenty for the rode.

Now, about springlines... If you have a main dock off the bow or stern, you should definitely have at least one springline from a point aft on the finger dock. The issue is that if you have the bow and stern lines tight enough to keep the boat from moving fore-and-aft, they're probably too tight, and their angles could be such that any substantial force pushing the boat toward the main dock (such as another boat) could put undue stresses on the cleats. The bow and stern lines should position the boat side-to-side only, and be slack when there's no current or wind (which is why they shouldn't just lie over the cleat). If you have tidal issues, this becomes even more critical--the longer and looser the line, the less the rise and fall will affect the position of the boat. This also raises another argument for smaller (3/8") lines--you might need to have two lines on one cleat. (I had midship cleats on my genoa track for springlines. For major storms, I'd run springlines all the way to the bow and stern cleats.)

Stepping down off the soapbox...

Edited by - Dave Bristle on 02/08/2007 21:53:45

aeckhart
Master Marine Consultant

Members Avatar

USA
1709 Posts

Response Posted - 02/09/2007 : 06:36:01

Interesting topic. I've been using 1/2" dock lines since day one (18 yrs) only because I got a good deal on a 500' reel of the stuff and made an anchor road and five dock lines out of it. Since I use a mooring rather than a dock/pier, a good mooring road is most important. I've been using and all-chain road with a 5/8" nylon painter. I plan to replace the painter this year with 1/2" line. The 5/8" line has been in use for six years.

After 18 years, my dock lines are about due for replacement as well. Based on your discussion, I'd say that 3/8" line would be adequate for normal conditions and 1/2" spares for worst case situations.

Edited by - on

cat1951
Admiral

Members Avatar

USA
636 Posts

Response Posted - 02/09/2007 : 08:04:52

WOW... And here I thought this would be a short thread. I figured there were different sizes for moorings, protected slip, docked to one side, or anchored. Who knew...

Well I bought the 3/8" x 15' blue docklines. Got em for $12.59 each...so I figure it is cheap insurance for where we keep ours.

I did have kind of an interesting experience though. I had them set aside the lines for pick up after I got off work. The kid in the store started to say they couldn't match the internet special. That is until the store manager said something to him from the back room. I was fully prepared to go home and order them online if they would not have matched. Shipping would about equal the taxes.

Edited by - on

John Russell
Master Marine Consultant

Members Avatar

USA
3444 Posts

Response Posted - 02/09/2007 : 08:59:32

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Dave Bristle
 Well, to add to the opinions, here are mine, for what they're worth (roughly what you're paying for them)...

... Stepping down off the soapbox...

<hr height="1" noshade id="quote"></blockquote id="quote">

Dave, the difference between intelligence and wisdom is experience. (I used to say age but now that my beard is mostly gray......) The reason I value this forum is because I want to take advantage of the WISDOM that is here. Jump up on your soapbox whenever you feel the need.

Edited by - on

Frank Hopper
Past Commodore

Members Avatar

Pitcairn Island
6776 Posts

Response Posted - 02/09/2007 : 09:52:45

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by John Russell
 <blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Dave Bristle
 Well, to add to the opinions, here are mine, for what they're worth (roughly what you're paying for them)...

... Stepping down off the soapbox...

<hr height="1" noshade id="quote"></blockquote id="quote">
So how do you deal with the fact that I don't agree with most of what Dave said?

(psst, go with Dave.)

Edited by - on

John Russell
Master Marine Consultant

Members Avatar

USA
3444 Posts

Response Posted - 02/09/2007 : 10:11:48

All of your collective experiences go into the equation. The challenge for me is to choose which of the experiences are the most applicable to the issue I'm trying to resolve. Some of it boils down to who can make the most compelling case based on my own set of (often tangential) experiences. Nonetheless, it is the dialogue that contributes to the body of knowledge.

Better get off my soapbox.........

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 02/09/2007 : 10:32:22

I found some more stuff to add. First, I started thinking why I have ¾ line on the bow when I really only need half inch. (especially when the evil empire recommends 3/8 for a boat our size) Primarily it was a cost factor, as I received the line brand new for free. Secondarily however was that when it comes to weight, we are way on the other side of the curve. If you are not on an inland lake, or better stated if you can fall victim to storm surge, seche(sp?) or tidal fluctuations please consider the larger diameter lint.

My second thought was I don’t tie my lines on my boat with a Lark’s head knot (slip through the center back over the cleat) If you leave your lines at the dock , that knot can be a PITA – I thought I remembered reading about improper loading of the cleat when you do that, but I couldn’t find it.

Third – in my search for some of this information I ran into this story which has some interesting things – I didn’t read the entire thing and therefore don’t endorse anything in it – http://www.sailingbreezes.com/Sailing_Breezes_Current/Articles/may03/lines.htm

Also – along the same topic check out the piece in our club newsletter (commodores corner) located here: http://www.eycweb.com/motor_mast/pdfs/mm_2005_06_jun.pdf

Edited by - on

dlucier
Master Marine Consultant

Members Avatar

Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 02/09/2007 : 12:30:01

Duane,

After reading the piece concerning docklines in your yacht club's newsletter, I wonder how they concluded that the minimum dockline be 5/8" regardless of boat size?

Edited by - on

At Ease
Admiral

Members Avatar

672 Posts

Response Posted - 02/09/2007 : 12:45:59

5/8 is huge line...won't stretch much with a C25/250. I used 5/8 on a 43' 22,000 lbs houseboat.

Edited by - on

tinob
Master Marine Consultant

Members Avatar

USA
1883 Posts

Response Posted - 02/09/2007 : 13:25:30

I use 3/4"line because it's kindlier on arthritic hands. Use it on jibsheets and only 5/8" on mainsheet, when I replaced the mainsheet some years ago The arthritis hadn't gotten to my hands yet and so it stands, same for the haylards. My dock lines at the slip are 3/4" , it's what I had in the rope locker at the time. Anchor lines are 1/2" nylon. Docking lines on the go are 3/4"double braid (old jibsheet lines).

3/8" lines would slip through my hands now-a-days, just can't clamp down on it.

Val on the hard DAGNABIT,#3936,Patchogue, N.Y.

Edited by - on

Dave Bristle
Master Marine Consultant

Members Avatar

Djibouti
10005 Posts

Response Posted - 02/09/2007 : 13:31:13

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by John Russell
 [quote]Originally posted by Dave Bristle
 Dave, the difference between intelligence and wisdom is experience. (I used to say age but now that my beard is mostly gray......)<hr height="1" noshade id="quote"></blockquote id="quote">
They say wisdom comes with age, although sometimes age comes alone.

I agree that feeding a loop through the base of a cleat can be a pain, especially with a 1/2" line (which can barely do that on our boats). My preferred method is to drop the loop over the cleat, give the loop a half twist and slip it over the cleat again. You end up with the line crossed over the top of the cleat and running from its base toward the dock (thereby not improperly loading the cleat, I think). It goes on and off very easily, but cannot fall off, and works with oversized lines.

Edited by - Dave Bristle on 02/09/2007 13:47:56

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 02/09/2007 : 14:18:54

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by dlucier
 Duane,

After reading the piece concerning docklines in your yacht club's newsletter, I wonder how they concluded that the minimum dockline be 5/8" regardless of boat size?
<hr height="1" noshade id="quote"></blockquote id="quote">

Don, I’d attribute it do a number of things – but this is just my opinion.

First – the average boat size is probably about 33 feet. Based on the West Marine Calculation 9 goes into that 3 something so when you round up you get a half inch line. Add the extra 1/8 and you’d have your 5/8ths

Second – We get a huge storm surge when the wind is out of the North. I thought it was the equivalent of Seche (sp?) based on your prior posts but was corrected at a holiday party. It is surge, the old timers call it the bath tub effect. The basin has only a narrow inlet and is just outside of Cleveland’s Breakwall. Water comes in pretty hard but cant get out causing it to surge back and forth. 3 to 5 foot shifts in less than a couple of minutes. Extra is always good in these situations.

Third – our smallest dock is 30 feet, by looking at the dock chart (http://www.itsposted.com/www/DocsFormsApps/dockage/DOCK%20CHART%2011-1-06.pdf) I would guess the average is around 45 feet. Regardless then, you would be tying your 25 foot with 3/8th line a long way to get to the cleats or a really heavy large boat that fits in a 45 foot slip. ( I’m in a 44 foot dock ) If you’ve every tied up with your Jib sheets, you know that the additional length on something that heavy puts some serious looking strain on the line. I can only guess that visible strain translates into load. (as a side note, that main catwalk of A and B docks are almost a quarter mile long)

Fourth – We’ve seen what the surge can do to a guy with the wrong line diameter. Lets just say he’s lucky there is a fiberglass guy or two in town.

Edited by - on

Dave Bristle
Master Marine Consultant

Members Avatar

Djibouti
10005 Posts

Response Posted - 02/09/2007 : 14:40:58

Duane... I don't see how a longer line has more stress on it--I would think less, given that the line stretches a particular amount per unit length. I do know that if you have 3-5' shifts from your bathtub effect, the longer your lines, the less vertical angle they will go through, and therefore the less change in the position of your boat or likelihood that the cleats will be ripped off. Those of us in 7-9' tides have to deal with that every day.

Edited by - on

Page: of 2

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.