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poiu · 28-07-2014, 10:22

How about 12 strand dyneema? It is very light, especially because you can down-size, easy to splice a loop on the end, fairly chafe resistant, soft to handle.

It is slippy, but too slippy?

It doesn't stretch much, but too much stretch isn't good either.

I've not tried it, but it's good enough for oil tankers...

appick · 28-07-2014, 10:40

Agreed, that's why I like 3 strand for my dock lines lots of stretch to the line. I might also like it because it's usually the cheapest, but I'll stick to the bit about stretch.

I've wondered why some of my dock lines, whether it's 3 strand or double braid, stay pliable after years of use and others would be suitable for a jury rigged mast! It can't be salt because we're in the Great Lakes. I could buy the soot/ dirt from rain ect. I've soaked my lines in TSP substitute before and have been amazed at what you can get out.

appick · 28-07-2014, 10:41

... maybe I'm just using too march starch after I wash them!

lol

cwyckham · 28-07-2014, 11:28

Quote:

Originally Posted by poiu

How about 12 strand dyneema? It is very light, especially because you can down-size, easy to splice a loop on the end, fairly chafe resistant, soft to handle.

It is slippy, but too slippy?

It doesn't stretch much, but too much stretch isn't good either.

I've not tried it, but it's good enough for oil tankers...

This is just about the worst case scenario. Docklines need to be large enough to handle easily and have good stretch. Dyneema is more money for a less suitable product. It may also slip on the cleats.

Sandero · 28-07-2014, 11:46

I have some NE ropes or Samson and can't remember how old they are... they are fine... BUT I don't spend a lot of time tied to docks either..

Stumble · 28-07-2014, 12:39

Quote:

Originally Posted by poiu

How about 12 strand dyneema? It is very light, especially because you can down-size, easy to splice a loop on the end, fairly chafe resistant, soft to handle.

It is slippy, but too slippy?

It doesn't stretch much, but too much stretch isn't good either.

I've not tried it, but it's good enough for oil tankers...

While I love dyneema and use it everywhere it is wholy unsuited for use as docklines for a small boat. The lack of stretch means that it will shock load the boat on every passing swell.

Oil tankers and other large ships use it because they have very different issues. The next best option is 6" steal hawsers which also don't stretch, but do weigh tons. Litterly tons. Cargo vessels also want to be held as still and as close to the dock as possible in order to make loading and unloading possible. So they not only tie up, they also winch the lines in to press the side of the boat up against the dock. This keeps them in position for cranes and whatnot, but it isn't a practice that is reasonable for recreational vessels.

Of course dyneema chaff sleaves are amazing. And are worlds better than anything else on the market.

thinwater · 28-07-2014, 13:31

^^ what Rubin said re. Dyneema.

The one exception is that while 4-corner lines and breast lines need some stretch, polyester halyards (not Dyneema) can be just right for long spring lines. They are longer and thus still have enough stretch, where nylon can have a bit too much stretch in long lengths..

**a64pilot** · 28-07-2014, 14:28

Quote:

Originally Posted by savoir

Mega yachts are not a fair comparison. So long as the product looks sexy and does the job they are there. Price doesn't matter.

You mean highly polished SS anchors, don't hold better?

poiu · 28-07-2014, 18:10

Quote:

Originally Posted by thinwater

^^ what Rubin said re. Dyneema.

The one exception is that while 4-corner lines and breast lines need some stretch, polyester halyards (not Dyneema) can be just right for long spring lines. They are longer and thus still have enough stretch, where nylon can have a bit too much stretch in long lengths..

Polyester makes more sense to me than nylon in long lengths, but I wonder if dyneema really would be so bad as you and Rubin believe. I found this where dyneema seemed to work:

SetSailÂ» Blog Archive Â» Dock Lines For A Bouncy Harbor

Randyonr3 · 29-07-2014, 12:57

Quote:

Originally Posted by LakeSuperior

Docklines and halyards/sheets serve opposed functions. Using halyards for docklines is generally considered to be poor seamanship. Ideal halyards have zero stretch.

Docklines are designed to stretch in order to reduce peak acceleration impulses transmitted to the boat. No stretch docklines will transmit shock impulses through every piece of hardware attached to the hull and deck. You are putting unnecessary wear and tear on the whole boat. This is a bad idea.

Halyards "sta-set-x" works great for dock lines as long as you use rubber snubbers which should be used on your boat anyway..
and the "poor seamanship" remark... **** dude, you must be a dock cop..

LakeSuperior · 29-07-2014, 13:08

Quote:

Originally Posted by Randyonr3

Halyards "sta-set-x" works great for dock lines as long as you use rubber snubbers which should be used on your boat anyway..
and the "poor seamanship" remark... **** dude, you must be a dock cop..

The bottom line for me is when I see halyards being used as docklines one thought always and instantly comes to mind...clueless!

Rubber snubbers unless precisely sized for max loads (loads depend on the boat mass and the boat speed as function of slack in the dock lines) don't solve the problem. The boat will reach the slack limit of the snubber and then be jerked to an abrupt stop.

thinwater · 29-07-2014, 13:22

"Dock cop." I like that.

Like most things, tie-ups vary, boats vary, and thus we have a range of good answers. IMHO, one of the smartest things you can do is sleep on the boat a few nights, through the tides, weather changes and wakes, and see how she moves. Adjust accordingly. Every boat I've owned has been tied up a bit differently, to suit the size, weight, and motion. I'm pretty sure I could make most materials work, though I'd be hesitant about HMPE lines. Give them to someone with a smaller boat, where they will make great genoa sheets.

Stumble · 29-07-2014, 15:13

Quote:

Originally Posted by poiu

Polyester makes more sense to me than nylon in long lengths, but I wonder if dyneema really would be so bad as you and Rubin believe. I found this where dyneema seemed to work:

SetSailÂ» Blog Archive Â» Dock Lines For A Bouncy Harbor

I am aware of what Dashew does, and I normally wouldn't argue with him. But there are major differences here.

1) his boat is much bigger and heavier than what we are talking about here.
2) he used dyneema in conjunction with other constructions to manage docking. He is actually using dyneema, polyester, and nylon for various reasons. Most of us aren't willing or able to carry three sets of dock lines of different material. And pull the ideal line for that purpose.
3) he mentioned how uncomfortable the dyneema is in this application.
4) take a look at the bollard cleats he has. He is using 3" schedule 40 pipe thru welded into the bowels of the ship. These are orders of magnitude stronger than any hard point on most vessels. Shock loads he can absorb would rip the cleats off most boats.
5) where he is using dyneema is very short runs where the stretch of nylon wouldn't matter much.

Just like with very large ships Dashew has designed a system that meets his needs. Those needs are just very different than what the average cruiser needs. For instance he uses the dyneema initially to get fast control over the boat. Which is a great idea when your regular set of docklines may weigh a couple of hundred pounds.

The reason he uses polyester for his spring lines btw is because his springs may approach 100' in leingth. Which given the size of the boat means that 1" nylon may stretch too much. Again this is the result of a near 80' boat that weighs in at 80,000lbs. Not really what most of us need to deal with.