Knots

[Gordon Maney]

Various sources will have various numbers, but for 5/8" nylon line the min. breaking strength is plus or minus 8900 lbft and the [B]safe load[B] is plus or minus 740 lbft.
DavidGB

The rope I am buying has a breaking strength of just over 18,000 lb.

[DavidGB]

knots

Sorry I was so slow to understand what was being asked,
DavidGB

[Clint Dixon]

If I understand correctly, the scenario outlined was created with the following constraints: The tractor for whatever reason is available as an anchor only (can't be moved to prestress line.) The line is just short of being able to go from the tractor to the tree and back to the tractor. I will also assume that there are no pulleys available.
Therefore the line must have one end first attached to the tree. (I agree that a bowline would be a good choice for that.) I would then create a loop in the line about 20' short of the tractor by tying a figure eight knot with a bend in the line (the first part of the "truckers hitch" mentioned in an earlier post.) After passing the bitter end around a suitable turning point on the tractor I would then bring it back to the loop and pull it through that. You now have a 2 to 1 advantage. You can gain more purchase by repeating legs of this cycle but with out pulleys friction becomes an increasing issue. This is like a large scale "truckers hitch" and I would finish it with a "slip" hitch knot.
I think this discussion is interesting in light of its' taking place in a Forum dedicated to trucks known for often having powerful PTO driven winches.
DavidGB

I really don't know anything about knots, let alone their names, but the technique you just described is what I have been doing for years. I use this method on everything from stringing a clothesline to tying down cargo in a pickup bed or on a trailer. I think it works really well. You can really tension a rope, it is easily adjustable as the rope stretches, and very easy to untie. Thanks for providing some terminology for it.

[Clint Dixon]

You really need a set of these Gordon

With all of the swap meets, flea markets, and farm auctions in your area, you should not have much trouble finding some of these rope hooks. I think they were used in barns and maybe with some other rigging applications. They work nice when erecting windmills, that's for sure!

The rope in the image is 3/4" diameter and is probably older than both you and I combined. It was made back when ropes were made out of what ropes should be made out of.

[Clint Dixon]

Knot started

The first hook is pretty simple. It relies upon friction to hold itself to the rope. It can be positioned anywhere along the rope and is easily moved. The loose end of the rope can then be tied back to the line under tension for some extra insurance.

[Clint Dixon]

Knot finished

Note that it has not been pulled tight yet

[Clint Dixon]

Knot started

This style is my favorite. It has some sort of sexy curves to it, don't you think?

[Clint Dixon]

Knot finished

This one was designed to work perfectly with the natural way a rope wants to lay through a knot.

[Clint Dixon]

I think these are called "Choker Hooks", at least that is what I use them for. They were designed for wire ripe (cable) but work equally as well with fiber rope as there are no sharp edges on either the hook or the eye. The large one accepts 1" diameter rope, the smaller accepts 3/8" diameter.

One of the best publications I have ever found detailing wire rope, fiber rope, knots, rigging, rope splicing, etc. is TM 5-225 - Rigging and Engineer Hand Tools. It was issued December 12, 1942. I have consulted various newer publications at times as a cross-reference, but I have found everything I needed to know right there in that 3/8" thick war department technical manual.

[Ron in Indiana]

Excellent pictures and equipment as always Clint. Finding a good old school hemp rope is a major score nowadays. Keep them dry and out of the weather they will last a long time. Choker hooks are fine for their intended purpose but have a tendency to kink or give a wire rope a "memory" on a heavy lift. I learned to tie knots in Scouts and use them often at work. I like a sheep shank knot to shorten a rope and because it was the one knot Fred McMurry couldn't tie in Follow Me Boys. I love that movie made by Disney because it reminds me of my dad who was a scoutmaster for 22 years before his death in 1988.

[Bruce]

Knots

By rementioning that the line is 150' long and the distance from the tree to the tractor is 80' it now occurs to me that you may be concerned with the fact that you have more line than you need. I don't see that as a problem. When securing to the tractor, instead of using the bitter end, just grab a "bight" (doubled over line) and make the bowline using that. Then coil up the tail and hang it on the tractor. When fastening to the tree and the tractor the more turns of line around the tree and the securing point on the tractor the less force is transmitted to tightening the knot.
DavidGB

This is called a "Bowline in a Bight" isn't it? I bet those Choker Hooks are as rare as hens teeth?

[DavidGB]

knots

Re: Bowline on a bight
What I meant to be describing is slightly different in that I would use the doubled over section of line as if it was the bitter end. In a bowline on a bight the final step involves flipping the loop, that is the end you created when doubling over the line to begin with, over the body of the knot before tightening it. You can't do that when creating a bowline around something. This is another way of creating a loop in aline.
DavidGB