Snatch Straps

What weght rating do I need for Hilux Dual Cab Diesel.
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Reply By: The Bantam - Monday, Apr 25, 2016 at 17:59

Monday, Apr 25, 2016 at 17:59
As per the Agreed industry guidelines the snatch strap minimum breaking strain should be between 2 and 3 tomes the Gross Vehicle Mass or the maximum loaded mass as the vehicle travels.
Link to Industry guidelines document.
https://www.juststraps.com.au/pdf/Snatch%20Straps%20Industry%20Guidelines%20Final%20March%2008%20Amended%20pdf.pdf
Hilux depending on model is a couple or three hundred KG under 3 tonnes GVM
That would make an 8 ish Tonne Minimum Breaking Strain strap appropriate.
Remember man
y after market recovery points are only good for 4.5 tonnes, so it is wise to use an equaliser strap and both recovery points.
cheers
AnswerID: 599155

Follow Up By: Frank P (NSW) - Monday, Apr 25, 2016 at 18:04

Monday, Apr 25, 2016 at 18:04
On using equaliser straps on recovery points ...

Both my front and rear recovery points are rated and placarded at 4.5 tonnes straight pull.

If you use an equaliser strap there will be a considerable sideways pull toward the middle. I guess the longer the equaliser strap the better, but I guess it's something to be considered in an extreme recovery.

Cheers
FrankP

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Follow Up By: Sigmund - Monday, Apr 25, 2016 at 18:53

Monday, Apr 25, 2016 at 18:53
Yep. On my vehicle it's 25% less than the total. Discount for skewed pull.
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Follow Up By: The Bantam - Monday, Apr 25, 2016 at 21:30

Monday, Apr 25, 2016 at 21:30
Sorry to get agro about this matter, but there is a lot of spurious bunkum, going around as arguments against using equaliser straps.

Sorry none of them hold any water. Most of us should be using equaliser straps on all recoveries.

Firtsly in any snatch recovery there may well be non straight line forces on the recovery points.

Secondly, if you have an snatch strap with a minimum breaking strain of 8 tonnes and a recovery point with a minumim breaking strain of 4.5 tonnes ( 9000 pounds), your system is badly compromised from the get go as the recovery point is a little more than half as strong as the snatch strap. HALF AS STRONG.

These popular 4.5 tonne hook type recovery points are commonly known to fail, either by straightening or fracturing when used as a single attachment point.
Simple maths no surprises there.

A friend of mine is a working motor engineer and 4wd competitor, he has seen many of these hooks fail.
His professional opinion is that the stamped rating is a fair estimate of the performance of the item.

In our recovery systems we do not want failures in hard tackle, a failed recovery point may result in a hard metal missile or at the least an attachment point that no longer works for another attempt.

In a snatch system, we should be making sure, it is the snatch strap that fails, firtsly because it is soft, secondly because it can be replaced and finally with repeated use a snatch strap WILL fail anyway.

Now to the equaliser strap.
While there are some "home made" equalisers that are way too short, ( like 1.5 meters) the commercial straps are at least 2.5 meters, I use a 3 meter strap.
If ya realy obsessed about the included angle and off line pull, use a 5 meter tree trunk protector.

With my 3 meter equaliser strap and my recovery hooks being on 640mm centres, that puts the included angle in the sling( equaliser strap) at 23 degrees and the off line pull on the recovery point at 11.5 degrees. ( assuming straight line pull)
These are the sort of angles that ya simply don't bother calculating derating for, because the derating is so low.

In a lifting sling, a 2 leg sling with an included angle of 60 degrees is rated at 1.7 times the strength of a straight single leg sling ...... my rig is around 20 degrees.
Nobody bothers calculating sling derating below 30 degrees.

So, if we use a long enough equaliser strap (for most 2.5 or 3 meters is plenty), neither the derating of the strap,nor the off line pull on the recovery points is an issue.

AND most importantly we end up with an attachment arangement using both recovery points that is TWICE AS STRONG and stronger than the snatch strap.

Now the third issue that does a lots of peoples heads in ...... the equaliser strap does not need to be as strong as the snatch strap .... a 6 tonne equaliser strap, will be good for around 12 tonnes of main line pull, and very much stronger than an 8 tonne snatch strap. As long as the included angle is less than 30 degrees.

There are some other arguments, for using equaliser straps.

There is the question of how well the recovery points are attached to the chassis ...... Yeh it is a question, but still many of those popular 4.5 tonne hooks get straightened or break with no damage to the chassis or fasteners.
But however strong the chassis and fasteners are ..... two attachment points will be twice as strong as one.

There is an argument that pulling on a single chassis rail, may twist the chassis ...... I recon that too is a bit of a long conclusion to draw ...... but still best to use an equaliser strap and two recovery points.

There has been some discussion about using towbars as a recovery point .
It is plain and clear that the tow ball should never be used.
Aparantly the tow bar manufacturers are happy with us using hitch reciever tow bars as recovery points. Although I can see some may be apprehensive.

Many times there are lower rated tongue only type towbars fitted to vehicles ...... Yeh I would not use one of those for anything other than a gentle tug.

I will use a recovery block in my hitch reciever tow bar ....... but if it became a tough recovery I'd be using, my equaliser strap and both rear recovery hooks mounted to my chassis.

cheers
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Follow Up By: Sigmund - Monday, Apr 25, 2016 at 21:38

Monday, Apr 25, 2016 at 21:38
The rating on a recovery point would be its working limit, not its breaking strain.
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Follow Up By: The Bantam - Monday, Apr 25, 2016 at 22:40

Monday, Apr 25, 2016 at 22:40
Unless there is explicit marking otherwise the only conclusion that can be drawn is that the rating is minimum breaking strain, with perhaps a very small engineering margin 1.5 to 1 maximum.

Considering it is an open hook and in comparison with similar items, 4.5 tonnes minimum breaking strain would be about right.

The experience of those who have seen these fail in use would indicate thet 4.5 tonnes minimum breaking strain is about right.

Consider the snatch strap and the equaliser strap will have similar engineering margins.

If an item is marked with "safe working load" or "Working Load Limit", it is regulated lifting equipment and will have specific markings, regulated lifting hardware has very large mandatory safety margins, minimum 4 to 1 .....

These popular recovery hooks do not have the marking that indicate it is working load, thus large safety margins can not be expected or assumed.

cheers
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Follow Up By: The Bantam - Monday, Apr 25, 2016 at 23:06

Monday, Apr 25, 2016 at 23:06
In the past these popular hooks came with nothing more than a figure stamped on the side in pounds, with no qualification.

More recently they are commong with W.L.L. 4500kg or such ..... these are not regulated lifting equipment, they do not comply with Australian standards for lifting equipment, and what the, "W.L.L." actually means is anybodies guess.

It could be argued, the because they do not comply and are not regulated lifting equipment the use of the "W.L.L." marking is illegal.

Above all ..... if you go to any manufacturer of lifting equipment, they will tell you in the specificatoions for the item what the safety factor is.

NONE of the suppliers of these items will give any meaningfull qualification to the 4500KG rating. ... well not that I have been able to find.

Consider they can be baught in lots of 200 or more, unpackaged ex Ningbo China at about $2 each ......
They retail her blister packed and with bolts for around $20
Don't expect too much.

cheers
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Follow Up By: Sigmund - Tuesday, Apr 26, 2016 at 05:04

Tuesday, Apr 26, 2016 at 05:04
WLL used to be called Safe Working Load. In my day the formula with steel was SWL is third of breaking strain.

Get a bolt on recovery point from ARB and it's an eye not a hook. Their guff clearly implies a correct setup is good for around 4.5 t. Not necessarily continuous.

My own wagon's manufacturer is happy to go on the record saying 2 t per point or 3 together.

Allan Whiting and Robert Pepper report strain gauge tests. One showed c. 4.8 t which Pepper described as violent. On sand Whiting found forces below half that.

If you have any doubt you can use Pepper's formula for calculating the strain in any given recovery situation. See The 4WD Handbook.
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Follow Up By: Frank P (NSW) - Tuesday, Apr 26, 2016 at 09:36

Tuesday, Apr 26, 2016 at 09:36
An interesting and informative discussion, gents. Thanks.

Bantam, you touched on the use of a recovery point in a receiver hitch point for snatch recoveries. I have often wondered about this - imposing up to, say, an 8 tonne load on a towbar designed to pull, say, 2.5 tonnes or thereabouts.

I have no idea what safety margins are built into a reputable, rated towbar, but it seems to me that the imposition of 8 tonnes on an item designed for 2.5 would be pushing the limits to say the least.

I believe it's not just the bar, but the side brackets and attachment points as well, as the picture posted by 671 indicates.

When I bought the factory recovery points for each end of the towbar on my BT50, the kit included substantial doublers for the side brackets.



That leads me to believe that using an unreinforced towbar for recoveries may introduce a relatively high risk of failure of the towbar or its mounting system - depending on its design.

I wonder how many people consider that when plugging a recovery point into their hitch receiver and "going for it".

Cheers
FrankP

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Follow Up By: garrycol - Tuesday, Apr 26, 2016 at 10:09

Tuesday, Apr 26, 2016 at 10:09
If you use a tree protector as an equilizer strap make sure you check its rating.

Tree protector straps are used when when winching not snatching and as such they generally have a much lower rating than a snatch strap so check their ratings.

My tree protector straps are rated at only half my snatch strap and match my winch extension strap.

So my point is to simply check the ratings of all your gearand ensure it matches - including your tree protectors.

Garry
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Follow Up By: gbc - Tuesday, Apr 26, 2016 at 10:11

Tuesday, Apr 26, 2016 at 10:11
There is a caveat to your included angle formula Bantam. The equaliser must be attached by each of the eyes to each of the attachment points - separately.
There have been numerous occasions when people simply feed the equaliser through each of the attachment points and then affix the tow/snatch to the eyes of the strap and then wonder why they have broken their car or bent their attachment points towards each other. The old 80 series (tie down) loops were shockers for this type of abuse.
The pulling from a single point twisting chassis rails is more relevant to monocoque chassis like the pajero which do have a history of doors not opening etc after a single leg tug.
I agree, 8t odd would be good, and agree with the rest as well.
2.5 t rated towbar is for 2.5t trailer weight. Pulling a 2.5t trailer up in an emergency will place many times that force through the bar. Ive done a few solid recoveries with towbar - abuse will kill anything, but I'm happy to use mine.
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Follow Up By: Sigmund - Tuesday, Apr 26, 2016 at 11:17

Tuesday, Apr 26, 2016 at 11:17
Yes, towbars are rated to pull a rolling weight and take a down force on the ball. You don't know what kind of pulling strain they're designed for.

That said thousands of snatch recoveries have been done with no ill effect. And you can't design out the effects of ignorance. Bottom line, if there's any doubt estimate the strain with the formula. Anything over 4.5t should raise the warning flag.

In terms of safe load v breaking strain, as I posted above, a rigger's rule for wire rope and chain is 1:3 and for fibre rope 1:6. A snatch strap in good condition and properly made will fall somewhere in between. If you buy a snatch strap, make sure the labelling is clear on what the rating refers to.
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Follow Up By: Batt's - Tuesday, Apr 26, 2016 at 12:59

Tuesday, Apr 26, 2016 at 12:59
Using an equalising strap is a good idea for a straight pull in ideal conditions but you also have to take into account that every vehicle is different and that if the manufacturer only recommends the vehicle has one dedicated recovery point which does happen then you should only use that. Just because some aftermarket companies supply a recovery hook for both side of a vehicle doesn't mean it is a good idea to fit them unless it has been tested and proven the vehicle's chassis is designed to cope with 2 recovery points.

As an example my first 4WD was a shorty 40 cruiser the recovery hook was on one side and the chassis was full box section on the other side part of the chassis was only C - channel not designed to use as a recovery point.
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Follow Up By: The Bantam - Tuesday, Apr 26, 2016 at 23:47

Tuesday, Apr 26, 2016 at 23:47
There are a whole pile of issues that realy do need to be discussed ..... so many simply are not aware.


Yes .... one does need to know how to use an equaliser strap ..... the ends of the strap should be in the recovery points and the line of pull rope or strap should be in the bight of the equalier ... and free to move.



On the matter of tree trunk protectors AND other equalisers
Remember the equaliser does not have to have the same rating as the line of pull strap.
Some people have a great deal of trouble understanding this (even some riggers and engineers) ....... an equaliser strap or a lifting sling in a two leg arrangement only needs to have half the rating of the required main line pull.

So a 6 tonne minimum breaking strain equaliser strap ( or tree trunk protector) is good for 12 tonnes of main line pull .... so is entirely adequate for an 8 tonne snatch strap.

On the matter of S.W.L. ( safe working load) ( the old term) or W.L.L. ( working load limit) .... they mean the same thing .....the mandatory safety factor in the lifting industry is 4 :1 for hard tackle such as shackles or hooks, most reputable items will have way higher safety factors 6:1 is not uncommon.

BUT ... neither term means a thing unless the item is stamped with the appropriate Australian standard number and the manufacturers ID mark. ...AND the supplier is prepared to provide certificates.

The W.L.L. mark on these popular hook tow/recovery points can not be trusted and must be ignored. No safety factor can be assumed.

The same applies to shackles and other hooks ....... unless the item bears an Australian standard number and a manufacturers ID ..... the markings mean nothing.

As far as safety factors on snatch straps and other recovery equipment .... IF the lable is "minimum breaking strain" that is exactly what it means ..... there may be a small enginering margin ..... less than 1.5:1 often much less ...... but there is no safety factor.

This is the same as height safety equipment ...... while in overhead lifting works on W.L.L. S.W.L.and similar ratings with overwhelmingly large safety factors, height safety equipment and recovery equipment work on "minimum breaking strain"

There is a 4wd industry term " Recovery Load limit" , but the safety factor is only 1.5 to 1. Spanset, a lifting manufacturer that also supplies recovery equipment flatly refuses to publish anything other than " minimum breaking strain" for its recovery products.

There are some interesting recent developments.

Most of the currently branded products of this nature are called "towing points" , even the items specifically manufactured and engineered for recovery purposes.

A lot of items that would have a year or two ago borned the word "RECOVERY" large on the packaging are now branded "TOWING".
I recon there is some ass covering going on.

On the matter of the high quality, purpose built, vehicle specific engineered attachment points ....... many of then will explicitly require the use of an equaliser strap. ...... look around and see if you can find one that does not.


On the matter of tow bars ...... yeh I certainly have some reservations ....... not the least is the leverage involved ...... very few tow bars are in line with the chassis.

There are specific strength requiremsnts for both tow bars and trailer drawbars set down in the ADRs and the referenced standards.
They are required to have substantial strength and to withstand a great deal more than the typically encountered towing and downforce.

The typical safety factors in design of towing equipment seems to be 1.5 to 1 as far as I have been able to establish. ..... 1.5 to 1 of what ... ahh that is the question.

As far as attachment of recovery points ....... yeh well .... that is another thing ....... and another discussion.

To all those that discuss or even argue about this ........ these matters need to be talked about more .... there is so much ignorance and misinformation about ..... and this IS a life safety issue.

cheers
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Follow Up By: LAZYLUX16 - Thursday, Apr 28, 2016 at 13:33

Thursday, Apr 28, 2016 at 13:33
How do you join Snatch Strap to Equaliser Strap thanks anybody ..
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Follow Up By: gbc - Thursday, Apr 28, 2016 at 13:49

Thursday, Apr 28, 2016 at 13:49
Just feed the equaliser through one eye of the snatch then attach each end of the equaliser to the car's recovery points. Never use a shackle or other such device.
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Reply By: 671 - Monday, Apr 25, 2016 at 20:12

Monday, Apr 25, 2016 at 20:12
It is not the strap that you have to worry about, it is the chassis. No car has been designed for snatch straps and the endless number of accidents with them is proof.

In this photo of a Hilux, the tow bar has been ripped off. Tow bars can come off but the number of hooks coming off would out number tow bars by hundreds to one. It is not the hooks that break, it is the thread coming off the bolts or the captive nuts being pulled out of the chassis.

The only way to make sure nothing comes off the car is to make the strap the weakest link in the chain. It must break before anything else.

I am not aware of anyone who has been injured or killed by a broken strap. It is what is on the end of them that has killed many people or done a lot of damage to the other car.



AnswerID: 599159

Follow Up By: LAZYLUX16 - Monday, Apr 25, 2016 at 21:27

Monday, Apr 25, 2016 at 21:27
671 did you see the tractor driver pulled out a vehicle, shackle went through the tractors windscreen and his face was a mess, also in my days working in Cooper Basin , a bulldozer pulled truck out with a chain and chain broke and a link got embed in Mechanics chest .Standing too close !! I have winch which I should have stated in original post , so do I really need snatch strap? Its my first time owning a Hilux and winch was already on it .I have only been bogged once before because I never listened to Aboriginal boys directions that was in my old 60 series Landcruiser. Never done a recovery with snatch strap or winch !
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Follow Up By: The Bantam - Monday, Apr 25, 2016 at 21:43

Monday, Apr 25, 2016 at 21:43
Snatch straps are much faster and more convienient than a winch for light recoveries.

One of the problems is, so many people the snatch strap is the be all and end oll of their recovery ideas.

cheers
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Follow Up By: 671 - Tuesday, Apr 26, 2016 at 19:55

Tuesday, Apr 26, 2016 at 19:55
LAZYLUX16 posted: "Standing too close !! "

Yes definitely. If you look at any training books on the use of snatch straps, you are told to get all onlookers back at least one and a half times the length of the strap. That sounds great and is just common sense but when you use them you have a person sitting in each car and right in line with the strap. That is where the most injuries and fatalities have occurred.

Could you imagine OH&S regulations allowing people to sit in that location if straps were used somewhere in industry? If people had to be there then a thick protective steel shield would be mandatory.

"so do I really need snatch strap? "

I never carry one but I do take a hand winch with me on some trips. Most of the four wheel driving that my wife and I do is on our own. This has been everywhere from Victorian mountain tracks to some of Len Beadell's desert tracks. Our rule is when you are alone you make sure you don't get stuck. Solo recovery can be very hard work with no guarantee of success.

A hand winch will pull the car in any direction. A front mounted winch won't. In open areas you may not have anything to anchor any type of winch to. Burying your spare wheel can make a good anchor but it is not much fun, particularly when you don't go deep enough and it pulls out. You then have to start again.

I have been around long enough to remember when snatch straps did not exist. I was a member of a Snowy Mountains based 4wd club back then. Stuck cars were recovered by towing, digging, jacking or winching.

When straps came along, everyone attached them to the towing hooks on the front of their cars. Over the years those hooks have become known are "rated" recovery points. They were towing only hooks back then and they still are today. The factory fitted hook on your Hilux will be a towing hook. The handbook will contain instructions for its use.

The aftermarket hooks in the 4wd accessory shop will also be labelled towing hooks. Replacing a factory fitted towing hook with an aftermarket towing hook does not instantly make it a rated recovery point suitable for snatch straps. You could say the same thing about tow bars. This is why so many have been torn off the chassis on both ends of cars with sometimes fatal results.

This DVD is a good example of what can happen.snatch strap accident In this case the strap and the hook from the towing car can be seen lying on the dash of the stranded car. It could have been imbedded in one of the occupants. You would expect a broken strap or a torn off hook to go straight to the attachment point on the other car but no, for some reason the end of the strap climbs and hits the window on the other car. Utube is full of examples like this


Many people will say it is ok to use them if you pull gently. I would imaging 6 kph would be gentle but look at the forces even that speed can generate.
shackle speed

The major problem with these things is you rarely know the condition of the attachment point on the other car. It is new or near new or has it been subjected to dozens of hard snatches and is ready to let go next time?
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Follow Up By: LAZYLUX16 - Tuesday, Apr 26, 2016 at 20:20

Tuesday, Apr 26, 2016 at 20:20
Well written 671, should be some manual published and put in every vehicle thats used offroad.Could call it the 671 manual..
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Reply By: MUZBRY- Life member(Vic) - Monday, Apr 25, 2016 at 20:37

Monday, Apr 25, 2016 at 20:37
Gday
Go and buy an 8 ton strap. If you get a good one it might tow 8 ton and if you buy a cheep one it might tow 4.5 ton , so you are covering all your bases . So an 8 ton one will do. The chances are that you will never take it out of the plastic wrapping.
Muzbry
Great place to be Mt Blue Rag 27/12/2012

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AnswerID: 599161

Follow Up By: LAZYLUX16 - Monday, Apr 25, 2016 at 21:32

Monday, Apr 25, 2016 at 21:32
Muzbry thanks.I have never been offroad yet in my Hilux so a bit wary and wanting to be safe now I have wife and son. I always have had Landcruisers never carried anything for recovery or had a winch.Just got through most situations or just dug myself out . cheers
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Follow Up By: MUZBRY- Life member(Vic) - Tuesday, Apr 26, 2016 at 07:40

Tuesday, Apr 26, 2016 at 07:40
Gday again
You must remember that the snatch strap you carry is not for you, its for the other fella that didnt buy one because "i wont need it". Make sure before you tow them out that you get your $80.00 first and then go buy another .
Muzbry
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Follow Up By: Batt's - Wednesday, Apr 27, 2016 at 21:56

Wednesday, Apr 27, 2016 at 21:56
I've never actually asked for money to recover anyone as yet could have made quite a few bucks over the yrs if I had maybe I'm too generous.
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Follow Up By: MUZBRY- Life member(Vic) - Thursday, Apr 28, 2016 at 08:40

Thursday, Apr 28, 2016 at 08:40
Gday Bats
Its not a towing fee, its the purchase price of the strap the other bloke needs to be towed.
You dont want a strap that has been draged through mud and sand, let the other bloke wash the strap, you buy a new one.
Muzbry
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Follow Up By: garrycol - Thursday, Apr 28, 2016 at 10:15

Thursday, Apr 28, 2016 at 10:15
So if they don't cough up the cash they don't get help. :-(

What is our society coming too. :-(

If I come across YOU out in the bush in trouble I will still offer to help YOU - free of charge and even if some of my gear gets damaged. I might not like it but I would still do it.

I will leave it there.
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Follow Up By: MUZBRY- Life member(Vic) - Thursday, Apr 28, 2016 at 13:28

Thursday, Apr 28, 2016 at 13:28
Gday Garry
You best meet me before judging me.
Muzbry
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Reply By: pop2jocem - Tuesday, Apr 26, 2016 at 10:48

Tuesday, Apr 26, 2016 at 10:48
Whether you use a winch or a "snatch strap" IMHO the biggest cause of gear failure is that a lot of people assume that they need do nothing more than hook up and go like a bat out of hell.
Many don't carry that most rudimentary and useful bit of kit. The long handled shovel.
Bogged up to the chassis rails in mud or sand you can reduce the required force to free yourself with a bit of digging. Not just around the wheels, which quite often can only exacerbate the problem.
Clearing as much as you can from the underbody will considerably reduce the force necessary to free your vehicle.
Many times you will be able to just drive out. Recovery equipment like Maxtraks also may be all you need after a bit of manual labour on the shovel.

Cheers
Pop
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Follow Up By: The Bantam - Tuesday, Apr 26, 2016 at 23:55

Tuesday, Apr 26, 2016 at 23:55
Jack Absalom was of the view that the billy can was one of the most usefull recovery tools.

Use the Billy can to brew a cup of tea ..... this gives you time to clam down and think.


cheers
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Reply By: Member - Phil G (SA) - Tuesday, Apr 26, 2016 at 21:28

Tuesday, Apr 26, 2016 at 21:28
Should not be greater than 8T for your Hilux. Some people simplistically think that bigger is better, but using a stronger strap simply means that you are more likely to break a recovery point. Strap should always be the weakest link.
AnswerID: 599197

Follow Up By: The Bantam - Tuesday, Apr 26, 2016 at 22:54

Tuesday, Apr 26, 2016 at 22:54
Using a strap according to the published guidelined will give the correct amount of SPdoing for the weight of your vehicle.

Using a ssnatch strap that is higher rated than necessary results in too much stiffness and too little spdoing.

cheers
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Follow Up By: 671 - Wednesday, Apr 27, 2016 at 20:42

Wednesday, Apr 27, 2016 at 20:42
"Strap should always be the weakest link."

Phil
How does an 8 ton strap become the weakest link when you are snatching off a 4500 kg towing hook? I have heard many people say you should replace the unmarked factory fitted towing hook with an aftermarket one and high tensile bolts. The problem is the hook seems to be ok, it is the bolts and the little factory fitted captive nuts inside the chassis that let go.

The smart operators tell you to use two hooks to spread the load but is that any safer? The handbook says do not tow at an angle let alone snatch at an angle.

A tow bar is attached to both sides of the chassis but that did not stop the one in the photo that I posted from being ripped off. The bar simply pivoted on the rear bolt and pulled the front bolt and its captive nut down through the side of the chassis like a knife then out through the bottom flange. The rear bolt then enlarged the hole in the chassis and pulled the captive nut through.

On my Hilux the bolts, captive nuts and chassis metal gauge at the front are exactly the same.

You often hear the saying " its in the too hard basket". Despite all the snatch strap accidents and injuries/fatalities, people still use them and try and claim they are ok when used correctly. I think the thought of being in the bush without them seems to be in the "too inconvenient basket".
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Follow Up By: Member - Phil G (SA) - Wednesday, Apr 27, 2016 at 22:29

Wednesday, Apr 27, 2016 at 22:29
Yep you are right 671. Perhaps I should have revised it down to 5000kg in the case of the Hilux. Have to say I was surprised at how thin your Hilux chassis looked. Maybe that is why they are only rated to tow 2250kg? So maybe the guideline of 2-3 times GVM could be changed for the Hilux. But to have a towbar pull out of a chassis is a rare event which doesn't often feature in Coroners reports.Home made towbars and rusty old towbars do.

And yes, a snatch recovery can be sooooo unsafe. It is too easy to buy a strap, get it out of its box and use it any way you like. When I was younger and used to drive on beaches, we'd see it all the time.

But firstly, bolting a 4500kg point to a weaker chassis is inherently dangerous. It is unusual for them to be called recovery points, they are usually called tow points by their manufacturers for obvious reasons. I am always amused why we buy recovery points made from 10mm steel and bolt them to a chassis made from 2.5mm steel.
Secondly, for the past 15 years I have been a firm believer in using an equaliser strap to make a snatch recovery safe. If a recovery point breaks, it is retained by the other side and the guy in the other car doesn't cop it in the back of his head.
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Follow Up By: Member - Phil G (SA) - Wednesday, Apr 27, 2016 at 22:39

Wednesday, Apr 27, 2016 at 22:39
What's interesting, was that 11 years ago on this forum, we were having exactly the same conversations:
https://www.exploroz.com/Forum/Topic/21326/recovery_gearspecifically_shackles.aspx
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Follow Up By: The Bantam - Thursday, Apr 28, 2016 at 00:11

Thursday, Apr 28, 2016 at 00:11
I'm hearing a whole pile of "why bother" and not much in the way of actual facts or even an idea of relative engineeing understanding or the correct way of doing it.

Firstly, yes there are issues of strength of connection to the chassis. ... there always will be.

Now .... here is a very serious question ...... has anybody got actual first hand experience of a properly fitted attachment point pulling out of a chassis when used with an equaliser strap.
Exactly what where the circumstances.

These captive nuts that supposedly pulled out of the chassis ....... was the recovery/tow point being used in something like an inline pull ...... that being putting the bolts and the connection to the chassis in sheer.

The picture shown up the page shows a failure that looks very much like it was pulled out of the side of the chassis.... not from an inline pull

The fact of the matter is .... an overwhelming amount of the time, the factory fitted captive nuts DO NOT pull out.

If you are grosely overloading a recovery/tow point .... like 8 tonnes on a 4.5 tonne point ..... a variety of failures could be expected ...... if a grosely overloaded point is also loaded at a significant out of line angle ...... it is very likely to pull the captive nuts out of the chassis

BTW .... does the concept of "twice as strong" mean anything to people.

we have seen a couple of failure images posted ...... but do we know the circumstances?

any tow bar that is connected with only 2 bolts on each side is not going to be very strong.

MY tow bar ..... vehicle with a rated maximum towing capacity of 1.8 tonnes and a towbar certified for that maximum capacity, has two bolts in each outer chassi rail, a tounge extending down each side of the chassis rail into a hole in the chassis as an anti rotation measure and another bolt each side up thru the bottom of each chassi rail. This is pretty typical of a turn of the century hilux. It is a hitch reciever tow bar.

NOW, the towbar this vehicle originally came with was only rated at 1 tonne. it was a plain tongue towbar ....... plain tongue tow bars are generaly rated 1 tonne or less ..... it only had two bolts each side and no anti-rotation tongue .

There is a world of difference between these two tow bars ..... one is around twice as strong as the other.

The towbar manufacturers seem to be happy for hitch reciever towbars to be used as recovery attachments ...... I doubt that any hitch reciever tow bar will be attached with only 2 bolts each side.

We should not be using plain tongue tow bars for recoveries.

BTW, I have seen exactly the same model as mine, with exacty the same tow bar, that has been rear ended, big time ...... the tow bar attachments remained in tact and in place, but the whole rear section of the chassis behind the rear spring hangers was bent down about 45 degrees ..... I don't think the towbar will pull out any time soon.



Twice as strong IS what you get when using an equaliser strap and two recovery points.

Saying anything other than using two recovery points and an equaliser strap being twice as strong is safer is plainly rediculous.



Now to the connection of recovery points to the chassis.

much depends on what those captive bolts where intended for and what else is going on with that chassis.
the front of my, turn of the century hilux has two bolts thru the bottom of the chassis, and two bolts thru the side of the chassis each side.
these are intended to mount either the factory bumper or an aftermarket bullbar.

The bottom pairs of bolts mount that factory towing points., that now carry my recovery points.
This is a closed box section with a double thickness of plate, top and bottom.
there is a great deal of difference between that and a single thickness u shaped chassis rail ........ it would probably be "twice as strong"


It is easy to bleat and say why bother, when some not up to task attachment fails, but it des not mean every or in fact any properly fitted attachment will fail.


I know that there are people that are definitely "anti snatch strap" ...... I remember when they first became popular in the late seventies ...... many older hard core 4wders would not have a bar of them, claiming they where useless and incredibly dangerous.

They remain dangerous, when not used correctly.
But when used within the very specific guidlines they can be a very quick and very effective and very safe recovery device.

cheers
1
FollowupID: 868454

Follow Up By: 671 - Thursday, Apr 28, 2016 at 20:21

Thursday, Apr 28, 2016 at 20:21
"Have to say I was surprised at how thin your Hilux chassis looked.
I am always amused why we buy recovery points made from 10mm steel and bolt them to a chassis made from 2.5mm steel."

Phil
I put a micrometer on the rear end of my chassis recently and it measured approximately 3.3 mm. The problem with it, and all other cars, is it has not been designed for snatching. You will never break it if the car is used within its design limits but things like snatching or hanging far too much weight off the rear end of the chassis, particularly on rough roads, will eventually lead to failure.

I emailed Toyota in 2008 just after I bought the car and asked about the use of snatch straps. Their exact words in their reply were " Toyota does not support the use of snatch straps and our vehicles are not rated for them".

There has been so many breakages, not only on Toyotas, that they are not just covering their backsides, they are serious and the cars are not designed for them. If they were the hooks would never come off even after hundreds of flat out snatches. The handbook would also contain instructions for snatching, just like they do for towing.

If anyone wants a recovery point that has been designed for snatch straps then take the car to a suitable engineering company and have then redesign the chassis then sign off on it. That means you still have to worry about the other car though. Something flying off your car is not going to hurt you.

The tow bars on this particular model Hilux are attached with three bolts each side. There is the two captive nuts and the hole further forward for the extension to fit into as Bantam described. There are two more much larger holes in the lower flange. These can't be seen in the photo I posted.

Toyota's bolt kit contains three bolts for each side. One bolt has a large square plate and a nut for use on one of those larger holes. The other hole could be used because part of the bar reaches it and has a suitable hole in it but no bolt is supplied for it.

If the bar in the photo was a genuine Toyota and it came off on both sides, then it has ripped out six bolts. Such are the forces generated in snatching. There is no way in the world that I would use one.
0
FollowupID: 868505

Follow Up By: Member - Phil G (SA) - Thursday, Apr 28, 2016 at 20:47

Thursday, Apr 28, 2016 at 20:47
Hi 671,
The forces we generate when using a snatch strap are very dependant on the user. Some years back I learnt not to get bogged on the beach with incoming tide and I stay away from mud. So I'm unlikely to get in a situation where I need a huge force.
A quick bit of shovel work followed by a gentle tow or snatch is all I've done in recent years - usually to get someone over a dune or to tow a vehicle that has bottomed out. I still like to use an equaliser strap even though its not really required for a gentle snatch.

But I think the snatch strap is a great piece of gear for the gentle tow - the 20% stretch softens the jerking and I expect is easier on the recovery points. So I would never be without the snatch strap. Its just I would never use a snatch strap the way they were once marketed.
0
FollowupID: 868506

Follow Up By: The Bantam - Thursday, Apr 28, 2016 at 22:24

Thursday, Apr 28, 2016 at 22:24
SO 671, that picture you posted of a failed chassis is not yours and you do not know much about it, or the tow bar involved.

And you don't carry or use a snatch strap yourself.

It is very easy to point at failures wring you hands and say "Oh dear, all very dangerous"

There are plenty of failures and they will always occur when things are not done correctly or are grosely overloaded.

There reason there are so many accidents and failures with snatch straps ...... (there are hours of videos and reems of photographs) ..... is that, there are many people who are ill informed or willingly ignorant of correct and safe recover procedures.

We don't just bolt a 10mm recovery plate to a 3mm chassis rail ..... or at least we should not ..... we should be a little inteligent about how we attach these points and what we use for recoveries.

We should also conduct these recoveries with a little care ........ there are plenty of videos where people rip, tear and actually bust stuff, because their only understanding of recovery is more and faster.

I can not see how you can say that a hundred times more recovery points rip out than towbars ........ do you have any statistics or direct knoweledge of this.

As for vehicles not being designed for snatch straps ...... OH please, they are not designed to be driven thru mud or salt water either...... most off road activities would no meet with dealer approval.

If people take the time to understand the whole story, perhaps get some professional advice and take some straightforward care ....vehicle recoveries should be 100% safe, there should be no question of ripping out tow bars or recovery points.

There are thousands and thousands of simple, safe, quite booring recoveries every year using snatch straps.
Nothing damaged, nobody dies and it all happens quickly with a minumum of fuss.

Be sensible, use the published procedures ... and use an equaliser strap with both tow, snatch and winch recoveries .... it is twice as strong as a single point.

cheers
0
FollowupID: 868514

Follow Up By: 671 - Friday, Apr 29, 2016 at 00:05

Friday, Apr 29, 2016 at 00:05
Bantam

I have used a snatch strap once. That was 10 years ago during a professional driver training course. We went through all the procedures like checking the attachment points, clearing everyone out of the way, arranging signals when both drivers were ready, driving off slowly etc. Everything went smoothly and I thought they were ok. That was until I found all the accidents and fatalities on the net and contacted the car manufacturer. I have never used one since and never will.

If chassis were designed for straps, these incidents would not have happened. No matter how careful you are, the accidents and injuries are going to continue until cars are factory designed for straps.

If tow bars being used correctly occasionally fell off, there would be hell to play. They don't because they have been designed to tow a certain load and they will do it indefinitely. The hooks on the front have been designed for towing and snatching is definitely not towing. That is why they keep coming off. Claiming it is ok to use them if you have two is just guessing. You hope it is ok but you really don't know for sure.
-----------------------------
"We don't just bolt a 10mm recovery plate to a 3mm chassis rail ..... or at least we should not ..... we should be a little inteligent about how we attach these points and what we use for recoveries."
---------------------------------------

What do you bolt a recovery plate to then? Do you reinforce the chassis first? if you do then you would be the only one. You would of course need an engineering degree first then have the facilities to test a few prototype chassis to destruction like ARB tried doing a few years ago.
--------------------------------------
"Be sensible, use the published procedures ... and use an equaliser strap with both tow, snatch and winch recoveries .... it is twice as strong as a single point."
---------------------------------------
Who wrote these published procedures? Are you suggesting they overrule the car manufacturer's instructions?

An equaliser strap does spread the load a little but they are pulling the hooks sideways. The handbook for my car specifically says do not tow with the rope on an angle. I have a new Landcruiser ute hook from the early 1980s. The hook section is on an angle to the two mounting bolt holes. It has been made that way but they all seem to be straight these days.

An equaliser strap is very short and the angle to each hook is significant. Maybe if the equaliser was about fifty metres long, the middle of it would be almost twenty five metres in front of the stranded car. It may be safe to use it then but, without the engineering qualifications to work it out, you would still be guessing.

That is the way it will always be with snatch straps until cars are designed for them. There will always be a lot of wishing and hoping and guessing involved in their use. Some people will get away with it while others won't.

-------------------
"As for vehicles not being designed for snatch straps ...... OH please, they are not designed to be driven thru mud or salt water either...... most off road activities would no meet with dealer approval."
--------------------------------------------------------
Who said that? I have seen them being advertised on TV being driven through mud and salt water on the edge of surf. I have often wondered what they are going to do with the cars used in beach commercials. I hope the manufacturer does the right thing and crushes them.
































































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FollowupID: 868520

Follow Up By: The Bantam - Friday, Apr 29, 2016 at 09:43

Friday, Apr 29, 2016 at 09:43
Sorry 671, but that simply does not reflect sensible reality.

#1, all these snatch strap accidents are not because the vehicles where not designed for snatch straps ........ to say so is just plainly rediculous.

#2 to say that a properly fitted equaliser strap, pulls the hooks sideways in any significant degree, is also rediculous and simply ignores basic year 10 high school maths and geometry.

On most vehicles the equaliser strap only needs to be 2.5 to 3 meters long, to get the included angle so small, that its not worth bothering to calculate the sling angle or the inward force.
Don't make me publish the maths.

Equaliser straps, when correctly fitted are very effective in distributing the load across two recovery points, resulting in a connections that is with out question TWICE AS STRONG as using a single point.

#4 BTW, there are fully enginered and tested recovery points available from a number of suppliers, and yes where necessary they do reinforce the chassis.
These are commonly fitted to mine spec vehices, where they have OHS polocies and procedures for both towing and snatching ...... and yes they do use snatch straps.
I have been on suburban civil engineering / earthmoving sites, where they have formal polocies and provedures for the use of snatch straps on both light and heavy vehicles.

BTW many of these engineered recovery points require the use of an equaliser strap.

As for the rest of it ...... it is simply ill informed, fear, uncertaintly and doubt, that does not pay attention to the well documented facts. The reality and experience out there in the field proves it to be so.

cheers

cheers
0
FollowupID: 868531

Follow Up By: Frank P (NSW) - Friday, Apr 29, 2016 at 13:27

Friday, Apr 29, 2016 at 13:27
Out of interest I did some schoolboy maths on this, using my BT50 as an example.

The rear recovery points are 1.2m apart. If I used a 2.5m equaliser and had a straight 8 tonne pull from the centre of the equaliser, then there would be about 4.5 tonne of tension on each arm of the equaliser and about 2.2 tonne inward force on each recovery point.

The recovery points are held apart by the towbar, so the chassis rails are not going to pinch together. But if the recovery points themselves are too "thin" or poor material they will bend inwards or break.

The front recovery points are 900 apart. Using the same configuration with the equaliser, the tension on each leg of the strap would be about about 4.3 tonne and the inward force on each recovery point would be about 1.5 tonne.

Cheers
FrankP

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0
FollowupID: 868541

Follow Up By: 671 - Friday, Apr 29, 2016 at 21:18

Friday, Apr 29, 2016 at 21:18
"and the inward force on each recovery point would be about 1.5 tonne."

I wonder how much is too much on those hooks. I noticed the towing instructions in the hand book for my car recommend the use of a tow truck if the car has to be towed. If one is not available then the car can be towed by a chain or cable at low speeds on hard surface roads only. I get the impression that they have not designed the towing point to withstand a lot of stress.

I have read a lot of snatching accidents posts on the net since I started looking at 4wd forums ten years ago. So far I can't recall any examples of chassis failures at the front. It is always the bolts having their thread ripped off or pulling out of the captive nuts.
0
FollowupID: 868563

Follow Up By: Member - Phil G (SA) - Saturday, Apr 30, 2016 at 08:49

Saturday, Apr 30, 2016 at 08:49
671,
My ARB recovery points are slotted inwards to allow for any inner force.

Towing is restricted on modern vehicles because the transmission does not get lubricated without the motor running. Nothing to do with tow points
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FollowupID: 868570

Follow Up By: The Bantam - Saturday, Apr 30, 2016 at 10:22

Saturday, Apr 30, 2016 at 10:22
If your recovery points are 1.2 meters appart you should be using a 5 meter equaliser strap.
0
FollowupID: 868575

Follow Up By: Frank P (NSW) - Saturday, Apr 30, 2016 at 12:33

Saturday, Apr 30, 2016 at 12:33
Yes, Bantam, I figured a longer equaliser would be necessary.

The tow bar is very solid. For rear recoveries I'll probably use a recovery point in the receiver most times.

Cheers
FrankP

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0
FollowupID: 868583

Follow Up By: 671 - Saturday, Apr 30, 2016 at 21:01

Saturday, Apr 30, 2016 at 21:01
Towing is restricted on modern vehicles because the transmission does not get lubricated without the motor running. Nothing to do with tow points
-----------------------------------

That would explain why so many towing points have been ripped off by snatch straps. Car manufacturers don't have to go overboard with something designed for low speed short distance towing on good roads.

The same would apply to tow bars. A car can be designed to tow 3500 kgs which is way under the breaking point for the most commonly used snatch straps. Even then the only way to get a 3500 kgs pull onto a tow bar is to hook up a 3500kg trailer then lift the front of the car up with a crane and have the trailer dangling below it.

You would not get remotely close to a 3500 kg pull on the bar during towing.
0
FollowupID: 868598

Follow Up By: Member - Phil G (SA) - Sunday, May 01, 2016 at 16:57

Sunday, May 01, 2016 at 16:57
671 said:
"I noticed the towing instructions in the hand book for my car recommend the use of a tow truck if the car has to be towed. "

to which Phil replied:
"Towing is restricted on modern vehicles because the transmission does not get lubricated without the motor running. Nothing to do with tow points"

To which 671 continued about tow points getting ripped off.
0
FollowupID: 868627

Follow Up By: 671 - Sunday, May 01, 2016 at 21:11

Sunday, May 01, 2016 at 21:11
"To which 671 continued about tow points getting ripped off."

Well they do get ripped off Phil. It is the towing point that everyone attaches their snatch strap to or it is on my car. The identical chassis mounting point on the other side has a tie down point made from a flat piece of steel with a big hole in it and a 90 degree bend. Both sides use the same 12 mm high tensile bolts. The drivers side forged hook is for towing while the light bracket on the passenger's side is for tieing down. There is nothing else on the front of the car.
0
FollowupID: 868644

Follow Up By: Member - Phil G (SA) - Sunday, May 01, 2016 at 21:52

Sunday, May 01, 2016 at 21:52
"There is nothing else on the front of the car."

Which is why I went down to ARB and spent some money on two of their 4000kg rated recovery points that bolt to the chassis, and I use an equaliser strap, and I use a shovel, and I don't snatch hard.
No way I'll let me or anyone else be a victim of an unsafe recovery if I can avoid it.
0
FollowupID: 868646

Follow Up By: The Bantam - Sunday, May 01, 2016 at 22:22

Sunday, May 01, 2016 at 22:22
In deed you may not get full rated towing capacity forces appearing on a tow bar under normal towing.

BUT ..... VERY VERY BIG .... BUT

Towbars and drawbars are required by Australian Standard and ADR specification to withstand a great deal more than the rated capacity.
Up, down, sideways back and forward ..... all explicity specfied.

In an accident or abnormal stress situation towbars are required to deal with forces considerably greater than the towing capacity.

The actual failure sequence of the towing attachment is very well considered and more thoroughly designed than many may think.

It will take a great deal to seperate a properly installed towbar from the vehicle ....... watch some of the trailer fail videos and you will see how much it takes.

There are several Vids that show the tow vehicle being thrown around like a rag doll by the tow bar, without even the ball or coupling failing ..... which are the nominated failure points.
We do not recover using towballs, because they fail ...... it is argued they fail because they are intended to fail, before other parts of the system.


situations like this

https://www.youtube.com/watch?v=kwOqARlw1EI

trailer stays attached.

https://www.youtube.com/watch?v=-uvPIjaK01A

Trailer stays attached untill coupling fails.

https://www.youtube.com/watch?v=7mIDEeY210w

Yeh they do crash test this stuff

https://www.youtube.com/watch?v=nfTwXITM3SU

both vans still attached

https://www.youtube.com/watch?v=UM6FTYs7B2Y

Whats left of the caravan still attached.

https://www.youtube.com/watch?v=mfLnLwFcSBc

some pretty violent forces there

https://www.youtube.com/watch?v=GymlhreKW0Q

that one stayed attached too

and just for giggles

https://www.youtube.com/watch?v=htG_uXUev5A
0
FollowupID: 868647

Reply By: Member - Outback Gazz - Friday, Apr 29, 2016 at 06:48

Friday, Apr 29, 2016 at 06:48
Geez - after reading all the above, I hope all you blokes fill out your job safety anaysis forms and lodge them to the appropriate authorities !! lol
AnswerID: 599297

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