Question RE Making your own rigging rope

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My question is as follows:
"In making your own thread, is there a way to predict final rope diameter based on initial thread thickness and number of threads in rope?"
 
Great question. Your question is one of the reasons I have not yet tried making anything other than anchor rope which took a few guesses and tries to get to the right size.
I found an article that is very informative, except, I see no chart or information on calculating rope circumferences (or diameters). I tried measuring some miniature rope that I have on hand and came up the following. This is a tiny sampling so not nearly as indicative as a larger sampling would be. I did multiple wraps around a dowel so my measurements should be pretty close, at least I hope so. Hopefully someone here at SoS has additional, and more accurate, information.

Four strands
Overall diameter 0.072"
Each of the four strands 0.036

Overall 0.035"
Each strand 0.15"

The ratio seems to be about 2 to one for four strand


Three strands
Overall diameter .035"
Each strand 0.017"

The ratio seems to be about 2 to one for three strand as well.

I would guess that if a series of at least a dozen different size miniature ropes with various number of strands would yield a ratio that could be useful. The tightness of the rope mght also be a factor as well as the material.

Allan
 

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Great question. Your question is one of the reasons I have not yet tried making anything other than anchor rope which took a few guesses and tries to get to the right size.
I found an article that is very informative, except, I see no chart or information on calculating rope circumferences (or diameters). I tried measuring some miniature rope that I have on hand and came up the following. This is a tiny sampling so not nearly as indicative as a larger sampling would be. I did multiple wraps around a dowel so my measurements should be pretty close, at least I hope so. Hopefully someone here at SoS has additional, and more accurate, information.

Four strands
Overall diameter 0.072"
Each of the four strands 0.036

Overall 0.035"
Each strand 0.15"

The ratio seems to be about 2 to one for four strand


Three strands
Overall diameter .035"
Each strand 0.017"

The ratio seems to be about 2 to one for three strand as well.

I would guess that if a series of at least a dozen different size miniature ropes with various number of strands would yield a ratio that could be useful. The tightness of the rope mght also be a factor as well as the material.

Allan
thanks for the response. :)
 
Great question. Your question is one of the reasons I have not yet tried making anything other than anchor rope which took a few guesses and tries to get to the right size.
I found an article that is very informative, except, I see no chart or information on calculating rope circumferences (or diameters). I tried measuring some miniature rope that I have on hand and came up the following. This is a tiny sampling so not nearly as indicative as a larger sampling would be. I did multiple wraps around a dowel so my measurements should be pretty close, at least I hope so. Hopefully someone here at SoS has additional, and more accurate, information.

Four strands
Overall diameter 0.072"
Each of the four strands 0.036

Overall 0.035"
Each strand 0.15"

The ratio seems to be about 2 to one for four strand


Three strands
Overall diameter .035"
Each strand 0.017"

The ratio seems to be about 2 to one for three strand as well.

I would guess that if a series of at least a dozen different size miniature ropes with various number of strands would yield a ratio that could be useful. The tightness of the rope mght also be a factor as well as the material.

Allan
Thanks for a link to the PDF. It will be helpful.
 
Great question. Your question is one of the reasons I have not yet tried making anything other than anchor rope which took a few guesses and tries to get to the right size.
I found an article that is very informative, except, I see no chart or information on calculating rope circumferences (or diameters). I tried measuring some miniature rope that I have on hand and came up the following. This is a tiny sampling so not nearly as indicative as a larger sampling would be. I did multiple wraps around a dowel so my measurements should be pretty close, at least I hope so. Hopefully someone here at SoS has additional, and more accurate, information.

Four strands
Overall diameter 0.072"
Each of the four strands 0.036

Overall 0.035"
Each strand 0.15"

The ratio seems to be about 2 to one for four strand


Three strands
Overall diameter .035"
Each strand 0.017"

The ratio seems to be about 2 to one for three strand as well.

I would guess that if a series of at least a dozen different size miniature ropes with various number of strands would yield a ratio that could be useful. The tightness of the rope mght also be a factor as well as the material.

Allan
i have a planetary gear type rope making machine. I have yet to use it as I have not needed to make rope until now. The kit I purchased sadly doesn`t have enough rope to complete all the rigging, and I was thinking of using the machine. I was trying to put some science towards making ropes. I think I`ll have to set up some sort of experimental design of experiments and see what I get, which is ok. I don`t mind this sort of stuff because I am in no hurry.
 
There is no way to accurately predict final rope diameter for unknown threads / yarns but making tests. For known thread brands and models there could be charts. I use only the attached ones. I experiment with different rope constructions as I go. For example I made 1 x 4 constructions with some yarns to get rope diameters that are not in the chart.

1746018330182.png

1746018345719.png
 
There is no way to accurately predict final rope diameter for unknown threads / yarns but making tests. For known thread brands and models there could be charts. I use only the attached ones. I experiment with different rope constructions as I go. For example I made 1 x 4 constructions with some yarns to get rope diameters that are not in the chart.

View attachment 516700

View attachment 516701
ok. thanks for the info. I have different size threads so I can play around a little before actually making what I need.
 
Hi Allan, but the basis of all the rigging reasoning, you have to know the various diameters of the individual lines and then reproduce to scale
Franco
From the chart above I did a quick search for diameter of Skala 240 thread and got the following:
The Guerman Gutermann Skala 240 thread, with a Tex of 12 (denier weight of 108), has a diameter of approximately 0.12mm.

In this case 0.12mm three ply Gutermnan yields 0.22mm rope according to line 2 in the chart above, which is about double the individual thread diameter just as in the quick test I did earlier.

So if I want 0.22mm rope I can use 0.12 mm thread. Correct?

Allan
 
i have a planetary gear type rope making machine. I have yet to use it as I have not needed to make rope until now. The kit I purchased sadly doesn`t have enough rope to complete all the rigging, and I was thinking of using the machine. I was trying to put some science towards making ropes. I think I`ll have to set up some sort of experimental design of experiments and see what I get, which is ok. I don`t mind this sort of stuff because I am in no hurry.
There are multiple you tube videos describing different rope walking machines and how they work. There are also numerous articles on SOS and other sites.

Rob
 
There is a great tutorial here on SOS with a lot of explanation why and how.

 
Franco
From the chart above I did a quick search for diameter of Skala 240 thread and got the following:
The Guerman Gutermann Skala 240 thread, with a Tex of 12 (denier weight of 108), has a diameter of approximately 0.12mm.

In this case 0.12mm three ply Gutermnan yields 0.22mm rope according to line 2 in the chart above, which is about double the individual thread diameter just as in the quick test I did earlier.

So if I want 0.22mm rope I can use 0.12 mm thread. Correct?

Allan
Sorry Allan, there is a translation problem, this is not what I was explaining.Frank
 
There is a great tutorial here on SOS with a lot of explanation why and how.

great information. thanks
 
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