Author Topic: Calculating Rope Needed for Knot  (Read 7221 times)

Lady Bug

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Calculating Rope Needed for Knot
« on: May 03, 2021, 02:49:48 PM »
Newbie here, I?m glad I found your forum. I need a bit of help. I am planning on purchasing a 1.5? manilla rope to hang from the tree in our backyard for the kids to climb. The company I?m ordering from offers a rope eye splice at the top to facilitate hanging, a poly boot at the bottom to prevent fraying, and cuts to custom lengths.
My problem is that I want to tie over hand knots every 1.5 feet to help the children climb into the tree. In order to get the correct length of rope, I need to know how much rope length will be used for each knot. Does anyone know how much rope length I?d need for each knot or know how I can figure this out (without having the rope already in my possession)?

Also, if you have any better knots I should use for my purposes or any additional factors I should consider before purchasing the rope, I?d love to hear them as well. Thank you.

siriuso

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Re: Calculating Rope Needed for Knot
« Reply #1 on: May 03, 2021, 09:26:21 PM »
Lady Bug

1. Made markings just on top and bottom of the knot as shown.
2. Untie the knot, the length of the knot is the distance between the markings.

Happy Knotting
yChan

Lady Bug

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Re: Calculating Rope Needed for Knot
« Reply #2 on: May 04, 2021, 01:12:38 AM »
Yes, but has anyone done this with a 1.5 inch rope? Or is there a formula to extrapolate it from a different thickness of rope? I do not have any rope that thick to test it on.
« Last Edit: May 04, 2021, 01:14:15 AM by Lady Bug »

SS369

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Re: Calculating Rope Needed for Knot
« Reply #3 on: May 04, 2021, 08:04:03 PM »
Good day Lady Bug.

I just went out to my 1.5 inch diameter climbing rope and tied an Overhand knot and reasonably snugged it. I did not add my weight to it because it is wet and I don?t want a permanent knot in it.

A rope of this size will require 20 inches Per Overhand knot.

This will add a lot of length to the whole affair prior to tying all those.

You might consider tying a series of tight knots at the desired intervals, such as Strangle, constrictor, Turks head knots using separate pieces of smaller diameter rope or cord. It just needs to a large enough node to aid them.
 Since the climbers will no doubt not need such huge knots in their future.

I have even thought of opening the strands of the rope and passing a smaller diameter rope through it and tying it off.

Hope this helps.

SS

KC

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Re: Calculating Rope Needed for Knot
« Reply #4 on: May 07, 2021, 09:16:17 PM »
More than I thought!
.
i would consider if really need knots inviting  kids to top at branch or not.
"Nature, to be commanded, must be obeyed" -Sir Francis Bacon
We now return you to the safety of normal thinking peoples.
~ Please excuse the interruption; thanx -the mgmt.~

Lady Bug

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Re: Calculating Rope Needed for Knot
« Reply #5 on: May 07, 2021, 09:39:01 PM »
SS369,
Wow! I?m glad I asked for a bit of help rather than just going for it. That is more than I would have guessed. Thank you for helping me with this.
I do think you?re right though. I will order the rope of the length I need and work on tying on a series of smaller knots for grip when it arrives.
Thank you so much for the advice!