Hand vs electric winch: solo travelling

Tank, all your experience and all you write is absolutely correct for situations you are writing about. Eg The bosuns chair self lift thing. Sit in harness at one end of the rope, round a single pulley, pull the other end. No MA at all. Disadvantage only.

A situation we shall here call "apples".

The rig that is set up when a typical winch equipped vehicle runs cable out to a remote snatch block and back to the vehicle is not - apples. It's oranges.

The difference between these apples and oranges, is the that the apples bosuns chair set up has one pulley - the oranges setup has TWO pulleys in the system even if it's not obvious. The winch drum itself is the second pulley. A power driven pulley, not passive, both providing the "pull" and supporting a share of the load.

A bosuns chair arrangement that equates to "oranges" (vehicle mounted winch recovery incorporating a single snatch lock) is this:
Nice sit harness attached to a rope,
the rope passed around a remote pulley, back to ANOTHER pulley attached to the sit harness. The passenger/load pulling (awkwardly!) by extending his arms away from his body.

Everyone seems to love their tirfor winches.
I have a high lift jack and a jack-mate block to replace the base. With the addition of a few lengths of chain to my existing rigging, this can be used as a (slow) winching device.

What's peoples thoughts on this?

My reasoning for this route might be along the lines of the ability to lift vertically with the hi lift as well as horizontally. Electric winch is also available.

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Originally Posted by ramblingboy42

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I just could not see the point in large run-up engine screaming , kangaroo hopping up a more difficult track , and that's what the others were doing.

So , with me it's not so much skillful driving and vehicle preparation. just chicken ****!

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Seems to me more like a case of a "mechanicals sympathetic" driving style.

A bit like you where, whilst I like testing limits and knowing capabilities and taking on a challenge, if it's likely to mean work afterwards - I'll prefer the easier path. So for me it's more a case of laziness than the more dignified "mechanically sympathetic".

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Originally Posted by tact

Tank, all your experience and all you write is absolutely correct for situations you are writing about. Eg The bosuns chair self lift thing. Sit in harness at one end of the rope, round a single pulley, pull the other end. No MA at all. Disadvantage only.

A situation we shall here call "apples".

The rig that is set up when a typical winch equipped vehicle runs cable out to a remote snatch block and back to the vehicle is not - apples. It's oranges.

The difference between these apples and oranges, is the that the apples bosuns chair set up has one pulley - the oranges setup has TWO pulleys in the system even if it's not obvious. The winch drum itself is the second pulley. A power driven pulley, not passive, both providing the "pull" and supporting a share of the load.

A bosuns chair arrangement that equates to "oranges" (vehicle mounted winch recovery incorporating a single snatch lock) is this:
Nice sit harness attached to a rope,
the rope passed around a remote pulley, back to ANOTHER pulley attached to the sit harness. The passenger/load pulling (awkwardly!) by extending his arms away from his body.

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careful with your wording...

if you are sitting in the in the harness and pulling the rope, you're rigged to advantage......

if the setup you're talking about is...
rope attached to an elevated point, the pully is supporting the chair and someone else pulls the other end of the rope thats rigged to advantage

if the setup is...

pully attached to a high point, you sit in the harness and someone else pulls the rope, thats disadvantage.

https://www.aulro.com/afvb/images/im...015/10/941.jpg
...with a defender for extra cool points.

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Originally Posted by Blknight.aus

careful with your wording...

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Watching wording indeed please. I never referred to "rigged to (dis)advantage" - the term with a specific technical meaning. Tried keeping all I wrote non-technical. Unless apples and oranges are in the riggers handbook too - then my apologies.

I wrote "no MA at all. disadvantage only." The disadvantage being frictional losses added to the load burden with no mechanical advantage to mitigate.

Neil, if someone else is pulling on the rope, what you have said about no MA is true.

If the person sitting in the chair is doing the pulling, then it is exactly the same as a 4WD with a rope going from the winch, around a pulley and back to the vehicle. In that case there is a theoretical MA of 2 with some small loss caused by the pulley.

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Originally Posted by vnx205

Neil, if someone else is pulling on the rope, what you have said about no MA is true.

If the person sitting in the chair is doing the pulling, then it is exactly the same as a 4WD with a rope going from the winch, around a pulley and back to the vehicle. In that case there is a theoretical MA of 2 with some small loss caused by the pulley.

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You are sitting in the chair. Rope up and over a pully back to your hands. You pull 1M of rope. How much higher off the ground is your bum in the chair? (1M)

You are sitting in the chair. Same chair. Same rope. Your mate standing behind you pulls in 1M of rope. How much higher is your bum in the chair now off the ground? (1M)

(All "apples")

Now it's time for oranges. You in the same chair. Same rope up and over the same single pulley. Difference this time, you feed the rope around a pulley attached to your harness/chair ... And you or your mate pull up towards the first pulley (above you). You pull in 1M of rope. Your bum goes up how far? (1/2M)

Oranges example is what you have in a normal 4x4 vehicle equipped with a winch and rope is passed through a remote snatch block and back to the vehicle. (Wind 1M of winch rope onto the drum and car moves forward 1/2m)

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Originally Posted by tact

You are sitting in the chair. Rope up and over a pully back to your hands. You pull 1M of rope. How much higher off the ground is your bum in the chair? (1M) Wrong

You are sitting in the chair. Same chair. Same rope. Your mate standing behind you pulls in 1M of rope. How much higher is your bum in the chair now off the ground? (1M) Right

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Have you ever tried this? I can't believe how few people seem to have actually tried it. As a young teenager I used to regularly do it and the rope didn't pass through a pulley at the top. It just went over a wooden rafter. I had to overcome the friction of the rope passing over a square hardwood rafter and I could still manage it.

In the diagram below, the total length of the rope (ignoring the little bit around the pulley) is 2 metres.

If the person in the chair pulls in 1 metre of rope as in the right hand part of the diagram, how long would X and Y be? So how much closer to the top pulley is the chair?