Kinetic Recovery Rope for Unimog??

[Jolly Roger]

I'm looking for a kinetic recovery rope for use with a Unimog. The GVW of the vehicle is around 17,600 lbs (8,000 kgs).

I've seen a couple of nice ropes online, one with a capacity of 33,500 lbs and another with a capacity of just over 52,000 lbs. I was thinking of getting the higher capacity rope, but it was brought to my attention that the 33,500 capacity rope may be a better choice if I ever need recovery assistance from a smaller vehicle (Land Rover, Land Cruiser, etc.). The thought being that the smaller vehicles would be able to develop more kinetic energy with the smaller rope than with the larger rope.

Soooo . . . as a complete noob to anything to do with recovery, I thought I'd throw this out to all of your experts out there. Which rope would you buy and why? Or, if there is a different rope I should consider, please feel free to chime in on the benefits of that one.

Thanks in advance for your help.

 

[Eventhough]

I would always size my recovery equipment to my vehicle, not a potentially smaller vehicle that might be assisting in the recovery. I understand your logic and agree that a smaller vehicle might not be able to create enough dynamic energy to stretch a very thick recovery rope sufficiently - BUT - if it can you do NOT want the rope breaking.

Imagine a smaller vehicle trying to snatch a huge concrete and steel reinforced pillar out of the ground that is buried 10 feet deep (this is you). If the Unimog doesn't budge all the energy generated by the smaller vehicle will transfer to the recovery rope, possibly break it, and then you are playing one fast paced game of jump rope.

 

[Token]

http://www.bubbarope.com/

Get a smaller one (28.6) and a heavy one (74k)..

 

[opie]

You should be aiming for a rope rated @ 3-4 times your vehicle weight. These ropes dont reached their advertised maximum stretch until they are near or at their breaking point. And in order to store as much of that energy as possible, you want to ride that line as closely as possibly. A smaller vehicle is going to transfer the same amount of energy to either line, but in a larger line it will release that energy slower than a smaller line.

Using any type of kinetic product is basically a guessing game. You are trying to harness a violent reaction and use it to your advantage. If I had to err on one side or the other, Id go bigger. I would rather take the chance of not having a higher percentage of efficiency than risk the product breaking and coming through my windshield. When you get into the 1", 1.25" and 1.5", thats a considerable amount of weight to be coming at you and if it does break, rest easy knowing that the rope has stored more energy than it can handle, and its going to happen fast.

 

[garrett]

We use 1 1/4" Masterpull kinetic "Super Yanker" that is rated for 52,300 lbs. We're training with everything from Defender 110s, BJ75s, Hiluxes, etc. It works great for our applications, but wouldn't hesitate to use it for larger applications as well.

You can go up to 1 1/2" that's rated around 72K.

The military uses these ropes on their 50,000 lb MRAPs. They are using 2" that is rated for 131,000 lbs.

If you really want the best opinion call Masterpull directly. They know their products better than anyone.

 

[Master-Pull]

When we sell ropes we guide people to purchase items for their own personal vehicle. More then likely you will be using your ropes to pull someone else out. So with a mog like yours I would suggest a 1 1/4 rope, rated to 52,000 lbs, using a 3:1 rating for tow ropes works out pretty well.

Just to show you how well a kinetic can work, here is one of our 3/4 inch ropes in Europe. I don't know how badly the semi was stuck, but it's a cool little video.

[ame="http://www.youtube.com/watch?v=awTzEBdO0kk"]YouTube - www.laptopid.ee Porsche Cayenne towing 15 tons truck[/ame]

-Alex

 

[Master-Pull]

Also how far up into BC are you? We are in Bellingham, if you want to come visit the shop sometime feel free. We have walk ins from time to time, and we can show you a few different products to help you make the best decision.

-Alex

 

[Jolly Roger]

Thanks for all of your comments and suggestions. It seems that the consensus of opinion is to get one of the heavier ropes (52,000 lbs ish). Hopefully there will be few situations where my Mog is actually stuck, but I want to be prepared just in case. As Alex pointed out, its probably more likely that I will be pulling someone else out, as opposed to having them pull me out.

I'm also in the process of saving my pennies for a winch. I'm guessing that I should be going for something fairly heavy-duty such as a 25,000 - 30,000 lb? As with the straps and ropes, I've had a number of different opinions as to how much capacity I'd need in a winch. I'd rather have too much capacity than not enough. However, having said that, I don't want to purchase something that is way beyond what I would ever conceivably need. Any advice or recommendations for a good winch? High capacity winches tend to be fairly pricey so I want to ensure I make the best decision prior selling my wife and mother-in-law on eBay in order to finance the winch.

As always, your advice and recommendations are much appreciated.

Many thanks

 

[Jolly Roger]

Also how far up into BC are you? We are in Bellingham, if you want to come visit the shop sometime feel free. We have walk ins from time to time, and we can show you a few different products to help you make the best decision.

-Alex

I'm just in Chilliwack which isn't far from Bellingham at all. I usually pop over the border a couple of times a month so next time I'm heading down I'll give you a shout. It would be nice to see some of these products in person.

 

[Master-Pull]

Stop in and we can show you ropes, blocks, shackles, everything catered towards larger vehicles. You would like a winch that can pull at least 1.5x the vehicle weight ideally. Which is tough on a larger vehicle such as a mog.

-Alex

 

[GeoScum]

The thought being that the smaller vehicles would be able to develop more kinetic energy with the smaller rope than with the larger rope

If the puller hits the end of both ropes at the same velocity, equal amounts of energy will be stored in either rope. Because the smaller rope could be expected to stretch more, it would hold less potential energy as a function of rope length than the thicker rope.

 

[Jolly Roger]

If the puller hits the end of both ropes at the same velocity, equal amounts of energy will be stored in either rope. Because the smaller rope could be expected to stretch more, it would hold less potential energy as a function of rope length than the thicker rope.

Sorry, I'm not really following what you are saying. You mentioned that both ropes would store the same mount of energy if the pulling force was the same. However, you then mention that the smaller rope would hold less potential energy as a function of rope length. What exactly does that mean and how would it translate to extracting a stuck vehicle? I knew I should have paid more attention in physics class!

 

[GeoScum]

It isn't strictly applicable in all cases because there are so many variables, The rope, the puller, the stuck truck and their respective velocities.

What I was referring to, was in the rare and specific case where the pulling vehicle stretches the rope and then itself is stopped or almost stopped, the stretch as it is released will not be as strong as the thicker rope, but will last much longer.

In fact, a chain acts as a kinetic recovery device. But the stretch is so little, and it recovery is so quick, that it is not noticeable

 

[Jolly Roger]

It isn't strictly applicable in all cases because there are so many variables, The rope, the puller, the stuck truck and their respective velocities.

What I was referring to, was in the rare and specific case where the pulling vehicle stretches the rope and then itself is stopped or almost stopped, the stretch as it is released will not be as strong as the thicker rope, but will last much longer.

In fact, a chain acts as a kinetic recovery device. But the stretch is so little, and it recovery is so quick, that it is not noticeable

So based on this, is it better to have a shorter but stronger pull (thin rope) or longer but weaker pull (thick rope)? Or, will that vary depending on all of the conditions you mentioned?

 

[GeoScum]

Forget the multivariable calculus and buy a rope sized appropriately for your truck, and not based on any other theoretical vehicles