Thread: Rope for extension straps.

All good frank
But it does amuse me that you flame someone for using the wrong size pulley block or a shackle oriented vertically instead of horizontally however you are more than happy to run your sacred do not kink or twist me wire rope around car bodies to the crush them?

I'm sure if I am ever in the situation of needing to do some demolition work I'll come up with a plan

I thought we were discussing recovery? Oh and yeah I have moved a few dumped vehicles from trails (using dynema) but I didn't see the point in crushing them?

S

Originally Posted by roverrescue

All good frank
But it does amuse me that you flame someone for using the wrong size pulley block or a shackle oriented vertically instead of horizontally however you are more than happy to run your sacred do not kink or twist me wire rope around car bodies to the crush them?

I'm sure if I am ever in the situation of needing to do some demolition work I'll come up with a plan

I thought we were discussing recovery? Oh and yeah I have moved a few dumped vehicles from trails (using dynema) but I didn't see the point in crushing them?

S

The 16mm wire rope on the scrap truck is not used for recovery (it's too slow) and it has no kinks or broken wires even though it has a hard life.
My point is there are no situations in recovery that I would hesitate to use my Disco winch wire rope for, but there are many I wouldn't/couldn't use Dyneema type rope.
As far as shackles having the pin Vertical so as the shackle can align itself with the line of pull, well that's just commonsense, I've seen what damage a shackle can do if it is not used as designed, people have died, as far as using Dyneema rope, no problems, just not for me. you seem to have success with it, I'm not telling anyone to not use it, but it does help to know it's limitations, Regards Frank.

Originally Posted by Tank

I have never used Dyneema rope before, but I can imagine that a Bowline or any other Knot (bend or sheet) designed for natural fibre rope would slip and fuse under the friction of slipping.
Nylon ropes are banned in the Rigging industry for that reason as well as stretch and rebound (not Dyneema), esp, in blocks and tackles, most rigging knots, which were developed for sailing ships and Hemp and Sisal type ropes rely on the fact that their surfaces offer a lot of friction and use that fact to work properly.
Heat generated by friction is a killer for Nylon and Dyneema type ropes, I have busted Nylon rope when used in a truckies hitch, you will notice when you tie a truckies hitch with Nylon that you need 2 sheep shanks to stop the loop slipping and unravelling.
When I was head rigger at Cockatoo Island in Sydney I used to build my own specialist slings and we had an accredited test facility, so I have loaded and broken many wire slings, there really is not much flyback as stretch is minimal, usually the wires in the outer strands snap, gradually (Gives a warning unlike chain or nylon), and when individual strands break they unwind (each strand consists of a number of individual wires), they do not fly back to anchor points they unwind and not at a speed that requires a high speed camera to see, all this happens slowly compared to Dyneema that parts with no visible or audible sounds, (except for the tails of the break breaking the sound barrier, you know that loud crack) and springs back to each end, I know this stuff is light and it won't cut you in half, neither will wire rope unless you are stupid enough to be straddling it and are deaf and blind. My point is that wire rope is not as dangerous as some of these experts in 4WD magazines are making out and that wire rope is much more versatile and physically surface area strong.
I have recovered vehicles in areas where Dyneema rope either would not have done the job or survived intact after the job, whereas wire rope comes through to fight another day.
I have used the 15 ton hydraulic winch on my truck to crush 4 cars (2 bottom and 2 top) down to the height of one car, with no apparent damage to the wire cable.
Point is Dyneema is ok if you nurse it and maintain it (that's if you want it to last) and only occaisonly use it, I have an inbuilt mistrust of Nylon type ropes, Dyneema included and I can't see a scenario where I would use it over conventional rigging gear, to each his own, Regards Frank.

Sisal type???? we never used sisal under any load. Manila you meant I assume.

I use Synthetic on my winch and have a spare for an extension now. Much longer and much lighter than the straps I have. I splice all my ropes to my copy of The Admiralty Manual of Seamanship which does have some synthetic knots and splices.
Not me but a splice example you might like[ame="https://www.youtube.com/watch?v=pTM_BTq0qXY"]https://www.youtube.com/watch?v=pTM_BTq0qXY[/ame]

Originally Posted by NavyDiver

Sisal type???? we never used sisal under any load. Manila you meant I assume.

I use Synthetic on my winch and have a spare for an extension now. Much longer and much lighter than the straps I have. I splice all my ropes to my copy of The Admiralty Manual of Seamanship which does have some synthetic knots and splices.
Not me but a splice example you might likehttps://www.youtube.com/watch?v=pTM_BTq0qXY

I don't think Frank was suggesting that Sisal rope be used for load bearing. I think he was referring to it's frictional qualities only. I am sure you know full well that that is why it is used so commonly for lashing.

I'd look at how the snatch block was used. Instead of running the extension strap though the block, maybe you could have run the strap between your anchor point and the block. I've done it like this, and I had to run a second strap from the snatch block to a tree off to the side to put the angle of the recovery the way I needed it.

Originally Posted by Not_An_Abba_Fan

I'd look at how the snatch block was used. Instead of running the extension strap though the block, maybe you could have run the strap between your anchor point and the block. I've done it like this, and I had to run a second strap from the snatch block to a tree off to the side to put the angle of the recovery the way I needed it.

Nice drawings, better than mine, but you are not gaining a Mechanical Advantage by what you have sketched, except for the fact that you have twice the length of wire off the drum which gives you more pulling power. As we all know the maximum pull generated by the winch is with only one layer on the drum. with each consecutive layer of rope on the drum the pulling power of the winch diminishes, to the point that a fully loaded winch drum will only be rated at half or below it's advertised pulling capacity.
I would have in that situation, if I was able to get in front of the stuck vehicle, which you may not have been able or possible to do.
Attached the snatch block to the stuck vehicle and winched towards yourself (to advantage) and halving the load on the winch, there is a very interesting Pod Cast on 4x4 Earth on "16 4wd myths busted", part on snatch blocks starts around 37 minutes and goes to around 40 minutes, plenty of other interesting stuff as well, I will post up the Link, Regards Frank.

Link to Pod Cast: http://ec.libsyn.com/p/6/0/4/60415bc...&c_id=12032659

Originally Posted by NavyDiver

Sisal type???? we never used sisal under any load. Manila you meant I assume.

I use Synthetic on my winch and have a spare for an extension now. Much longer and much lighter than the straps I have. I splice all my ropes to my copy of The Admiralty Manual of Seamanship which does have some synthetic knots and splices.
Not me but a splice example you might likehttps://www.youtube.com/watch?v=pTM_BTq0qXY

Sure is a lot easier than splicing 5/8" 7 strand IWRC, couldn't understand why he didn't fit a thimble to the eye, the clevis pins on those hooks are very small and most winch Dyneema ropes that I have seen break, break at that point on the clevis pin. If a thimble is not used I would just make the eye and fit a decent size shackle with a pin with some girth.
My point about synthetic rope is that most of my winching is in recovering broken down or stranded vehicles in the high country behind Moruya, where I live.
Tuesday night I had to drive up to the top of Mericumbene FT to rescue a bloke and his son in a "Holden Captiva", amazed he got so far (almost to Mongamulla turnoff) from the DRY Creek Camping area and FT.
When we got to them we found that he had torn the guts out of all of his bash plates, tore his fuel tank to pieces, tore out the t/shaft centre bearing, the underside of this SUV looked like it had been chromed.
Because it was an Auto and we couldn't get to the front half shafts the front axles were winding up and causing drag, plus that these ****boxes weigh nearly 2 Tonne and he had 1/2 tonne in the back it was a nightmare to tow.
A fair few times I had to winch him up over some Eco Drains and the wire cable was digging grooves 45cm deep through the tops of some of the real steep ones.
Ended up stuffing my winch when the young bloke guiding the cable back onto the drum didn't bother because it was too hard (it really was) and the cable bunched up on one side of the drum and jambed and busted the steel bar cross bars which then jambed the drum against the bent in side plates and broke the driveshaft from the motor to the gearbox, so a new winch is on the way. My point being there is no way that you could have dragged Dyneema rope over them Eco Drains like the wire cable did.
So it's horses for courses, Dyneema got it's place, but not in the hard core stuff I put my winches through, Regards Frank

My suggestion was to avoid running the strap through the snatch block so you wouldn't damage the strap, nothing to do with mechanical advantage or anything else.