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Recovery and Towing


Tony B

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Stretchy tow ropes of any sort are the most dangerous of all, I have pulled the bumper and dumb irons off an old LR with one and seen a little Susuki recover a bogged RR almost 3 times it's weight with one.

 

The trouble is this type of recovery looks great fun and is spectacular to watch. Due to the dangers this should be discussed at length and discouraged, as winching is the much safer option.

 

I believe (someone may like to comment) the MOD bans KERR recovery on all soft skin vehicles.

 

Hear hear, I have seen front tow balls on Landies pulled off the front bumpers including the 24mm bolts with nuts and these have pulled straight through the mounting holes scares me to death.......

 

Anything which can transfer the acceleration + weight of a vehicle to something which is stationary and bogged is in for a surprise.....

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I've seen 'em ripped off with an ordinary rope never mind a Kerr rope, bolting a tow ball to a bumper is asking for trouble even with a spreader plate. Best method is a pair of Jate rings and then attach tow rope to a bridle rope joining the 2 Jate rings.

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As I stated earlier, I believe winching is much safer than other methods of dynamic recovery, because of the level of control available when using a winch. I would sway towards Antarmikes point that the danger levels are overplayed.

The horror stories seem to come from two areas;

1. offshore/fishing where many more factors come into play than a winching scenario on land. e.g. even a small swell can create massive additional forces.

2. 4x4 recreational use of small electric winches. It was possible (may still be) to buy a winch with a greater pull rating than the break strain of the cable it was fitted with.

 

For the general purposes of this forum neither of these apply as we are dealing with PTO driven equipment, where, as Mike pointed out, the rating of the winch is greater than that of the cable.

 

Here goes with a few points to think about.

 

1. The condition of the cable, check it out for damage and if it's knackered don't use it. More importantly don't damage it in the first place. In my experiance most damage occurs through poor spooling under tension, particularly when the cable is allowed to bunch at one end of the drum. The usual cause of this is poor rigging of the pull. This is less of a problem when using something with like a Matador as the fairleads are some distance from the drum and the cable tends to lay better. Using a rope dressing to lubricate it properly helps greatly.

 

2. Putting a blanket over the cable is a waste of time, I suspect it is unheard of on a fishing boat. If the pull is rigged properly, the cable snapping is not an issue. If there is a significant risk of a failure in the rig then re-rig it, rather than rely on an old coat.

 

3. "Always use gloves to guide the cable onto the drum"

If the cable is in good condition it should not be an issue.

If the cable is not in good condition it shoud not be being used.

If you need to guide it onto the drum, re-rig it.

If you really need to guide the cable, using a bar or a sling with a shackle is a better way of pushing and pulling it about.

It is probably more important to use gloves when using wire slings as they tend to get abused.

 

4. The weakest point of the rig is quite likely to be the attatchment point of whatever is being recovered. (wire slings again) Towing eyes are suprisingly easy to rip off. I once watched the official recovery crew at a 4x4 trial rip the entire front bumper off a lightweight by snatching it.

 

5. The best bit of safety advice I ever heard was courtesy of my dad. "never put your fingers where you wouldn't put your pri*k"

 

<Quote>

For the general purposes of this forum neither of these apply as we are dealing with PTO driven equipment, where, as Mike pointed out, the rating of the winch is greater than that of the cable.

 

On GMC trucks with winches the wire rope is hemp cored and 1/2" dia rated at 10,000 Lbs ( I think off hand ) for self recovery, but the pto drive shaft to the winch has a sheer pin fitted in it, I would hope this would fail before the cable snaped ( taking into account that the cable is in a safe to use condition ) so there is no instance that any danger could occure ?

 

With ref to the "4x4 winches" which are electric, I dont know of any, which have a cutout or sheer pin fitted so what stops the cable snapping on these when you have masive 4 and 5 HP motors geared down and most only fitted with 9mm cable ?

 

Ref point 2.. Does this work/any point to it, what happens to the bit of cable that doesn't have the "winch sail" on it ?

 

Does anyone out there know how a straight cable under heavy load fail conditions reacts ? Mythbusters did a similar thing and that just whiped back inline between the two fixed points.

 

Point 3.. Gloves to be used when winding cable on the drum !!! I thought, as in machine shops gloves were a no no as in it is better to get a cut rather than get a glove caught and pulled into the fair lead / drum before it can be stopped.

 

Please don't take any offence to any of this I am just posting points which have crossed my mind in the past at 4x4 events and assumed the marshals knew best !!

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That's that then! Winch as first option, towing only as last resort. Aside from powered winches, the Turfor is a very useful tool any one any thoughts on those?

 

I have a Turfor 32 will lift 3200Kg's has a 16mm cable and a sheer pin in the winching in lever, this is so if the sheer pin goes due to you trying to pull too much, you can still use the out lever to unload the Turfor, Its big heavy but if you are stranded and no engine power or electric winch this could save your life.

 

There is a certain model of Turfor which is safe to lift people ie it complies with safety factors on its cable and is classed a lifting machine.

Edited by R Cubed
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As a foot note to all this, did you know the domestic winches for 4x4 do not need any kind of safety factor for the cable, this is why they stress the point "this is not to be used for lifting purposes" the reason for this is as soon as you say lifting you are into Cranes and machines then you have to comply with loads and cable safety factors. So watch out as the winch you are standing by may well be able to exert a force if the motors up to it to snap the cable its fitted with, chances are the grip will be lost before but you always get the I know I will strap my vehicle to a tree and then I wont slide!!!!!!

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Does anyone out there know how a straight cable under heavy load fail conditions reacts ? Mythbusters did a similar thing and that just whiped back inline between the two fixed points.

 

Point 3.. Gloves to be used when winding cable on the drum !!! I thought, as in machine shops gloves were a no no as in it is better to get a cut rather than get a glove caught and pulled into the fair lead / drum before it can be stopped.

 

 

 

R,

 

I used to test and repair all winches in Army service. They had an annual requirement to have the cut outs and warnings checked as well as rope condition, etc. This covered all sorts of vehicles, Bedfords, AEC, Scammell, Foden, Leyland, dozers and loading shovels, recovery vehicles, armour, etc.

 

I once saw a rope that had broken on an AEC Mk1 Militant GS, whilst being tested by someone else, it broke at rear of lorry and ended up in a tree, the other side of the anchor block. This was the hemp core type rope. Later on the ropes on some vehicles were of a different construction and were said to drop down if they broke................not always, witnessed this as well. Despite very careful inspections, the rope can have been strained in the past and the damage not visible. We were having to load to the cut out, but theoretically, the SWL of the rope was double that. I am not sure a blanket or canvas would have much effect on a heavy rope, it goes so fast you have little warning. Just keep well clear. An operator should work out the load required to execute the task and never get up to the cut out load. You would not want to be pulling something up a bank only to cut out and have to let it back down again on the brake. The cut out is a safeguard. Some of heaviest winches were CAT D6 and Foden Recovery, the Foden could be done using the remote control well away from the vehicle, CAT not so good as there is only a sheet of glass between you and the winch. The cut outs were very often not correct or not working so it was a neccessary task.

 

Gloves.........if you slide your hand up a rope and there is a broken strand, it can slice open your finger or hand, much better to catch in the leather glove, as for getting caught in the winch, there is no need to be that close to the drum to guide it in.

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R,

 

I once saw a rope that had broken on an AEC Mk1 Militant GS, whilst being tested by someone else, it broke at rear of lorry and ended up in a tree, the other side of the anchor block. This was the hemp core type rope. Later on the ropes on some vehicles were of a different construction and were said to drop down if they broke................not always, witnessed this as well.

 

Did this just whip back along the line of pull, I can appreciate it might go further past one or the other end but generally in line with pull ?

 

 

Gloves.........if you slide your hand up a rope and there is a broken strand, it can slice open your finger or hand, much better to catch in the leather glove, as for getting caught in the winch, there is no need to be that close to the drum to guide it in.

 

I can see the use of gloves up the cable but have also seen people using them right by the winch :nono:

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Did this just whip back along the line of pull, I can appreciate it might go further past one or the other end but generally in line with pull ?

 

I can highly recommend the use of one of these devices when assessing the direction of travel a broken rope will take......

 

 

"Another batch of Wire Rope Failure Predictors awaits calibration before packing and despatch"

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Did this just whip back along the line of pull, I can appreciate it might go further past one or the other end but generally in line with pull ?

 

 

I would not say that a rope follows the direct line of pull when it breaks, if it is a considerably long length, there is a lot of energy contained as a rope pulls tight within it self, so there is a certain amount of flailing. The AEC rope was probably about 250 feet long as it was to full working length to carry out the test. It ended up over that length away from the lorry and high up in a tree, this is why I always ensured a wide zone around our testing, thankfully no accidents and hundreds of winches tested over the years.

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Just remembered whot the first one went to recover,its in Scotland,no rd nearby,

You wont believe it have a guess.

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