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Rat line tension tool


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...I worked bottom to top. I found that it worked best for me because with the knots on top it was

easy to see what I was doing and I could tap the knot down into the space between the boards

wth my tweezers to kind of set it in position and tighten it.

 

JMS

 

Which is in fact the best way to do it. After knotting the first ratline just put the planks on top of it - correct the level when necessary and knot the second ratline. Correct the level again by tapping the knot a bit down or up - white glue over it (you can do this in the end as well) and proceed to the top.

 

Another fact almost no one knows: due to shrinking of the rope the ratlines always had some more length than the space between the shrouds, they always hung a bit loose. So don't knot them as tight as possible - and the hourglass effect will not occur as well.

 

Nowadays, with other qualities of rope it is different of course.

Hans   

 

Owner of Kolderstok Models - 17th century Dutch ships.

 

Please visit www.kolderstok.com for an overview of the model kits available   

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  • 2 weeks later...

Good idea for a simple tool to make a difficult task easier !  But the title of the post is misleading or even wrong: ratlines don't actually need to be 'tensioned', in reality they are slightly sagging due to their own weight. This uniform sagging is rather difficult to reproduce, as the catena-shape changes as you proceed upward.

 

I would modify the tool a bit and drill two holes in the ends for a couple of machine screws with wing-nuts. But take caution not to squeeze the shrouds flat ...

Edited by wefalck

wefalck

 

panta rhei - Everything is in flux

 

 

M-et-M-72.jpg  Banner-AKHS-72.jpg  Banner-AAMM-72.jpg  ImagoOrbis-72.jpg
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  • 2 weeks later...

What a great idea.

I use a strip of rigid clear plastic as a spacer and guide.

But that does not stop what you call the hourglass effect which is always a problem.

The twin strips and sandpaper will sort that out a treat.

So I will be stealing this if you don't mind.

Nice one!!!

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John, thanks for the tip and the pictures. In my old age tying the rat lines is a real pita. My Benjamin W Latham was my first dealing with rat lines and I said I would never build another one that had rat lines. I'm about to start on my 3rd build which will be either the Model Shipways Niagra or the Rattlesnake, so this will be very helpful.

 

Thank you, Eddie

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Found a nice free wood provider for this idea, go into a starbucks and grab a few of the wood stirring sticks, nice size and a plentiful supply. :

 

Here in the States, one can go to the Dollar Store and pick up a nice size bag of them for a dollar.   I find a variety of uses for them.

 

My problem with going to Starbucks is, I hate their coffee. :)

Edited by mtaylor

Mark
"The shipwright is slow, but the wood is patient." - me

Current Build:                                                                                             
Past Builds:
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  • 2 weeks later...

I would like to thank every one for their comments and I am happy that this idea was received so positively.

It truly was a great help to me.

 

An interesting thing has happened to me and it brings to mind the old saying "practice makes perfect".

 

As I continued to tie the fair amount of rat lines on my project I felt as though my skills were improving.

I am nearing the end and almost at the top of the mast's now and it became a little cumbersome to use 

the guide so I started to try to tie the rat lines without it. I found out I do not need the guide anymore and can tie

a good rat line by eye. Maybe being at the top where there are fewer knots per line is somewhat easier but I 

believe I might not need the stretcher for the next project. 

 

I also found that by putting a very small drop of CA on each knot it wicks into the line by the knot slightly and

with some gentle downward force with my tweezers on each line between the knots I can achieve a nice gentle

and consistent droop to mimic the way an actual rat line looks. I really like the results and will continue this method

of finishing off the standing rigging.

 

JMS

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  • 3 months later...
On ‎12‎/‎12‎/‎2016 at 10:21 PM, Johnnymike said:

Allan

 

Yes, this is a model, the Prins Willem @100:1 scale so some things are not in exact scale. 

 

you might meant 1:100. otherwise, i don't think you have been building a boat. more like a city... just a pun...

 

Pavol stands for Paul, Pablo, Paolo etc. Please do not try to pronounce it, just call me Pav...

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  • 7 months later...

IMO,

A thick rope has heavy weight and that weight causes the shroud to hang due to gravity. The problem is at the first shroud (the closest to the mast). It must also have a sag but as same direction of the farthermost shroud (not like a hour glass). Actually full straight shrouds lines are not realistic.

And ratlines also have to sag due to gravity and after many usage from the crew...

Edited by Ferit KUTLU

Best Regards…

Ferit KUTLU

 

Under construction: Frigate Berlin (Brandenburg Navy)

Hope: Frigate Wappen Von Hamburg (Brandenburg Navy)

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You are right in principle, but achieving a uniform catenary as it were for all the shrouds, stays and back stays would be difficult to achieve. In practical terms I would go for uniform straight standing rigging. If you don’t get the catenary right, the model will look messy and poorly executed.

wefalck

 

panta rhei - Everything is in flux

 

 

M-et-M-72.jpg  Banner-AKHS-72.jpg  Banner-AAMM-72.jpg  ImagoOrbis-72.jpg
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Hi Ferit, wasn't the purpose of the lanyards (apart from providing an elastic/flexible interface) to enable a purchase to pull the catenary/sag out of the shrouds and then use the lanyards to hold that tension?  

 

cheers

 

Pat

If at first you do not suceed, try, and then try again!
Current build: HMCSS Victoria (Scratch)

Next build: HMAS Vampire (3D printed resin, scratch 1:350)

Built:          Battle Station (Scratch) and HM Bark Endeavour 1768 (kit 1:64)

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The purpose of the lanyards was to be able to adjust the shrouds as needed.  There are occasions were additional tension was applied to counteract forces on the mast.  The foremost shroud was occasionally slacked off to allow for bracing the yard up more sharply.  Also, no matter how well set up the mast would 'work' or move to some extent.  There would always be some adjustment of the shrouds necessary at some point.  Conversely, shrouds set up too tightly might cause a mast to be sprung because it was too stiff and could not work. 

 

Lanyards (with deadeyes or hearts) are employed because in a block and tackle the enormous forces involved would be concentrated on two points; the pins of the sheaves of the blocks.  Lanyards and deadeyes allow you to spread that load over six solid points not susceptible to breakage like a sheave pin.

Regards,

Edited by popeye2sea

Henry

 

Laissez le bon temps rouler ! 

 

 

Current Build:  Le Soleil Royal

Completed Build Amerigo Vespucci

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Actually, I wanted to express the final appearance  of the shrouds that the rules of physics obliged more than the working principle of all that rigging system as wefalck says at his last topic; "Given their size and weight, it would be impossible to put so much tension on them that they were completely straight. There is always a slight catenary in them."

Best Regards…

Ferit KUTLU

 

Under construction: Frigate Berlin (Brandenburg Navy)

Hope: Frigate Wappen Von Hamburg (Brandenburg Navy)

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On a model getting that slight catenary on the shrouds to look right would be difficult. They are like the rest of the rigging, in real life all the rigging sagged some, even under load. On a model, assuming the thread did not curl, or misshape itself when not under load, getting that sag would be very difficult. You also have to consider the audience  Others looking at your sagging rigging will just think you did a poor job.

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"Others looking at your sagging rigging will just think you did a poor job." - quite likely so ... same problem when reproducing a roughly built prototype ...

 

On running rigging, where loose and sagging looks more plausible even to uniniated bystanders, I have tried to reproduce the sag by wetting the line with fast-drying varnish and running a piece of wire along the line to maintain the catena (+/-) until the varnish has dried.

Edited by wefalck

wefalck

 

panta rhei - Everything is in flux

 

 

M-et-M-72.jpg  Banner-AKHS-72.jpg  Banner-AAMM-72.jpg  ImagoOrbis-72.jpg
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Shrouds are as tight as the crew can get them, all the time. Any slight bit of catinary can be measured in low single-digit inches on an actual ship and only very slightly noticeable if one sights along the shroud.  I’m all for realistic catinary in the rigging, but if you’ve got visible catinary on your small scale model then you’re representing a shroud that is unrealistically absolutely slack. Underway, the leeward shrouds will be looser than the windward ones due to the effect of the wind but it’s the kind of thing you could only notice by putting your hand on the shroud and giving it a tug. On ships with natural fiber rigging, keeping the shrouds tight is a constant chore as this material expands and contracts with the weather, but keep them tight they did as if they did not the masts would work and pump.

  

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