Making ropes take up catenary curves.

Smithy

Smithy

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When a rope is hanging loosely but supported at both ends it takes up a U shaped curve called a catenary.

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Here are some examples from the instructions to the Vanguard Models Alert (1777).

All of my rigging lines are both too light and too stiff to take up that shape naturally. Pulling them tight into straight lines is, of course, an option but is there a way to make nice smooth curves through the air like that?
 
Y.T. said:
May be soaking ropes in diluted PVA and hanging them loosely and letting them dry would provide this effect?
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Yes I've thought of that. I don't want to try it unless I know that it works, It would be very messy with drips onto the deck etc. I think it would be likely to stick to all the rigging that's already in place too. It would have to be done on the model to get all the parts of the line to line up. I would have a go if I saw a successful example though.
 
Can you tie an extra line as a test. Once in place wet it with artist's matte medium with your fingers or a brush but keep some paper towels on the deck. If a little drips it dries clear, but better it is caught on the way down to the deck. It is water soluble so easy to wipe up. This material is one of the major ingredients I was taught to use when making silk span sails rather than using glue as it dries clear, acts like glue, and is not expensive. One popular good quality brand is below.

Allan
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AllanKP69 said:
Can you tie an extra line as a test. Once in place wet it with artist's matte medium with your fingers or a brush but keep some paper towels on the deck. If a little drips it dries clear, but better it is caught on the way down to the deck. It is water soluble so easy to wipe up. This material is one of the major ingredients I was taught to use when making silk span sails rather than using glue as it dries clear, acts like glue, and is not expensive.

Allan
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Paper towels? Paper towels! Paper towels, why didn't I think of that?

I like the sound of matte medium rather than glue. Have you used it for this purpose yourself Allan?
 
I have used it on rope to seal a seizing but never put in drooping line which makes a lot of sense. Then again, other than schooners, it has been a very long time since I rigged a square rigger. If I ever finish the hull on my current build, Litchfield, (50) 1695, I plan to rig her.
 
Smithy said:
When a rope is hanging loosely but supported at both ends it takes up a U shaped curve called a catenary.

View attachment 495025

Here are some examples from the instructions to the Vanguard Models Alert (1777).

All of my rigging lines are both too light and too stiff to take up that shape naturally. Pulling them tight into straight lines is, of course, an option but is there a way to make nice smooth curves through the air like that?
Click to expand...
Are you sure they are meant to have that curve? Peterson shows curves like that for demonstration, which are hauled taut in reality.
Steel says (whether appropriate in this case or not?)
BOWLINES are fastened on and near the middle of the leech of square sails, by two or three subordinate parts, called bridles; and are used to brace sideways, or close-haul to the wind, the weather, or windward, leeches of the sails forward; which are kept steady by the tension of the bowline.

I interpret that as being taut. Boil me in oil if I'm wrong. :cool:
 
Masters Mate said:
Are you sure they are meant to have that curve? Peterson shows curves like that for demonstration, which are hauled taut in reality.
Steel says (whether appropriate in this case or not?)
BOWLINES are fastened on and near the middle of the leech of square sails, by two or three subordinate parts, called bridles; and are used to brace sideways, or close-haul to the wind, the weather, or windward, leeches of the sails forward; which are kept steady by the tension of the bowline.

I interpret that as being taut. Boil me in oil if I'm wrong. :cool:
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I don’t have sails so the ropes would be hanging slack, loosely tied to wherever they will be needed when the new sails arrive.
 
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If it is polyester rope, you can try to heat it a little bit up with a hairdryer.

And cotton rope, just wet it and let it dry in position.
 
Smithy said:
Have you actually used these methods in these circumstances? I ask because neither of them work for me.
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just guessing, because I make my own rope and when heating up polyester rope (baking in the oven) when it is turned, makes it very flexible when hot. I heat the rope in an oven to 175 degrees Celcius for about 1,5 to 5 minutes. But I think reheating it 1 minute could be enough.

And cotton takes up water and makes it heavy, that could be helping to hang it in a curve.

The problem with rope from a seller like amati, billing boats etc. is that it is stiff rope, when you make rope for yourself from lock yarn there is a choice you can make about the stiffness of you rope. You can make rope that is turned a lot (the 10% rule) to make it stiff and you can turn it less to make it flexible.
 
Steef66 said:
just guessing,
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I thought so. If I followed all of the guesses people have offered as answers my flat would be looking as singed as LA right now. ROTF

No worries, I’ll continue to experiment. Beeswax is looking good so far. Old school but still good stuff.



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Beeswax on Occre cotton thread. Neat!
 
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If you use Beeswax you will have a dust problem without a glass case to cover your model because it is essentially sticky. If yu like the method, I suggest that you wipe any surplus off with a hot towel before you use it on your model. I case of any difficulty, I bet there's a Turkish barber shop nearby who can advise.
 
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