How to pull cables over 1,200 feet when pull ropes aren't available in longer lengths?

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Have you ever noticed that a sheet bend and a bowline are the same knot?
I have knot! In fact I have never heard of a sheet bend so I looked it up:

"It is quick and easy to tie, and is considered so essential it is the first knot given in the Ashley Book of Knots.[1] Additionally, it is one of the six knots given in the International Guild of Knot Tyers' Six Knot Challenge, along with the clove hitch, bowline, reef knot (square knot), round turn and two half-hitches, and sheepshank."

Although I have worked with ropes from a young age rock climbing , building rope swings and a fair amount of tree work, I have never really been into knots or found any need for the vast majority of them.
 
A knot wouldn't work as added bulk would likely be prohibitive, and a catch point. You would need to actually weave the ends together making then one. Old time sailors all knew how to tie stranded ship ropes together I've seen ropes as big as 4 inch diameter spliced, I know larger have been done too.
When done a 3/4 inch rope only gains a 1/4 to 3/8 inch of diameter over length of splice and only moderately stiffer than the unspliced sections.
That would not fly in the San Francisco cable car system. The cable has to have uniform slip friction through the pinching grip of a cable car.
When the cable breaks, a field splice is made on the spot 20 or more feet long, and with no cars attached the splice is rotated into the powerhouse where a permanent splice is made overnight. That splice is, I believe, on the order of hundreds of feet long.
One of the powerhouse pulleys is on a long track and is moved out to take up strech in the cable and moved back when a new cable is fitted.
 
I have knot! In fact I have never heard of a sheet bend so I looked it up:
It is a simple way to attach a rope to the corner of a sheet such as a sail, or a tarp with no eyelets, or to join two ropes of different diameters. Bend the thicker part in a U, then tie with the thinner rope.

I have also taught people I see constantly retying their shoes to first reverse the first overhand knot, then finish the bow normally. I then explain the difference between a granny knot and a square knot.
 
How much can we overthink this. I tie ropes together all the time, had zero problems. We did a 700 foot pull two years ago of 250 URD in 2" PVC . Probably had to tie together 6 ropes as we had forgotten our long mule tape.
How come you can tie the rope to the pulling head or grip but can't tie the other end to another rope??? Ridiculous. Yes of course a knot is theoretically the weak point (I like the bowline 99% of the time. A figure 8 is a hair stronger) Yes of course you have to make sure the knot physically fits. Yes there is some common sense involved guys 😉
I hope your knots are listed for the purpose!
 
It is a simple way to attach a rope to the corner of a sheet such as a sail, or a tarp with no eyelets, or to join two ropes of different diameters. Bend the thicker part in a U, then tie with the thinner rope.
I seem to remember that in sailor lingo a "sheet" is a rope.
 
One of the powerhouse pulleys is on a long track and is moved out to take up strech in the cable and moved back when a new cable is fitted.
And it's kinda fun to watch the end sheave move along it's track as the rope stretches and slacks; there's something like a 20 ton weight holding it.

Trivia-
Over about 3/8" it becomes "wire rope" instead of cable and on the Cable Car division the round things are called sheaves, not pulleys. Friend used to be a cable car operator instructor, he was sort of adamant about that :LOL:.
 
Over about 3/8" it becomes "wire rope" instead of cable and on the Cable Car division the round things are called sheaves, not pulleys. Friend used to be a cable car operator instructor, he was sort of adamant about that :LOL:.
Sort of related but made me think of it. Several months ago was working with the POCO line crew on a project. Seems like lineman are always either super cool guys or super grumpy. This one grumpy one was going on and on about how someone called one of their poles a "telephone pole" and how much of an idiot he was because clearly it was a "utility pole". Maybe he took offense to being in any way shape or form associated with a telephone guy, kind of can't blame him 😂
 
One of my friends was an elevator mechanic. He told me an additional purpose of the rope core in wire rope was to act as an oil reservoir.
 
so speaking of ropes and stuff, here is one of me greatest rope creations, and one of my greatest accomplishments in life ;) It took a few painful face plants to get that down.

When I was much younger some friends and I we doing antics like that on a rope swing. I landed awkwardly and blew out my left eardrum; my hearing in that ear never completely recovered.
 
That would not fly in the San Francisco cable car system. The cable has to have uniform slip friction through the pinching grip of a cable car.
When the cable breaks, a field splice is made on the spot 20 or more feet long, and with no cars attached the splice is rotated into the powerhouse where a permanent splice is made overnight. That splice is, I believe, on the order of hundreds of feet long.
One of the powerhouse pulleys is on a long track and is moved out to take up strech in the cable and moved back when a new cable is fitted.
Similar to the cable "haul rope" on a ski lift, the two ends are braided together over a long length and the diameter is the same as the rest of the cable when it's done.
 
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