Recovery point conundrum

[makeitfit]

Absolutely, the guy's a twonk for sure:doh
However I have pulled and been pulled via the recovery points with no issues

 

[MudLifeCrisis]

I have pulled and been pulled via the recovery points with no issues

So have I but thankfully not that often now ;O)


As for the strength of metal , I managed to bend the towbar drop plate on mine and that was only on the Thetford greenlanes which are fairly mild ;O(

 

[makeitfit]

As for the strength of metal , I managed to bend the towbar drop plate on mine and that was only on the Thetford greenlanes which are fairly mild ;O(

Ah yes but now you're talking about bending moment and leverage and that:augie Where pulling from the recovery eye it is in sheer (neer enough anyway) So you should have as near as damn it the ultimate breaking strength of the steel, whatever that is, but huge I guess.
I'll have to get my old physics head in gear when sober and see what it actually is:sly Be interesting to work out:thumbs

 

[andrewk]

If you give that some welly when towing it out with say a kinetic rope several tonnes of load will make for interesting viewing:augie
I noticed on my kinetic rope it has a working load of 8 tonnes, which is a lot more than a cast ball hitch will take I reckon

A couple of points on this. Firstly, I don't think that any kinetic ropes have a working load of 8 tonnes. They usually have a breaking strength of 8 tonnes and a working load of 2 tonnes.

Secondly, towballs ain't cast, they are forged. The smallest section on the ball is the neck below the ball, it's a little over 1sq.in in section which means it is many times as strong as your kinetic rope. Even if it were cast (which it isn't), it would still be way stronger.

I wouldn't particularly recommend using a towball for recovery, mainly because there isn't really a secure way of fixing the rope or a shackle to the towball, rather than because they aren't strong enough (which they are). The nightmare stories about towball failures during offroad recovery seem to come mainly from Australia, where it's quite common to use towballs that are on a threaded pin fixed through a rear bumper. Recovery using one of those obviously isn't on. EU type approved towballs ain't the same animal at all and are massively stronger. I would have thought that a combination ball/pin would be a better solution, though the pins often have a lower rating than the ball, sometimes only 2 tonnes.

Just one last point before I whizz off on holiday (about 10 days before I see any more posts in this thread). The hole things shown on the photos at the start of this thread are lashing eyes not recovery points. My Patrol has these too and the handbook is VERY clear that they should not be used for recovery, as they are not strong enough. Recent Patrols have, as standard, a recovery eye welded onto a rectangular plate that fixes directly to the rear chassis cross member using 4 sizeable bolts. It is well above the towball and leaves plenty of clearance, even for an Alko stabilizer type caravan hitch. Maybe these are available for other Patrols too.

I understand that Mavericks and Terranos have similar lashing eyes at the rear and that many folks seem to use and recommend those for recovery. What does the original vehicle handbook say about that? I cannot understand how the lashing eyes on the rear of a Terrano can function any better as a recovery point than the similar (identical?) unsatisfactory lashing eyes on a Patrol.

Andrew

 

[solarman216]

Spot on Andrewk, could not agree more, Rick

 

[BongoBerry]

I understand that Mavericks and Terranos have similar lashing eyes at the rear and that many folks seem to use and recommend those for recovery. What does the original vehicle handbook say about that? I cannot understand how the lashing eyes on the rear of a Terrano can function any better as a recovery point than the similar (identical?) unsatisfactory lashing eyes on a Patrol.

Andrew

this seems to be the otherside of the coin, as its been clearly mentioned on this forum that the rear points are for recovery as opposed to tiw downs. It would be good to clear this up

Also, I don't think the assumption that many of the towball incicents happen in Austalia is due to poor uality tow balls. The logic does not stack up. There is a country who thrives on outdoor activities and build cars to suit. I'd put it down to the fact that based on how many recoveries / day that occur, Australia is going to be one of if not the highest, and hence the higher failure rate.

lastly - lets not get confused between recovery and towing. Vastly different beasts - in any country.

Tarrah

 

[Adz]

A couple of points on this. Firstly, I don't think that any kinetic ropes have a working load of 8 tonnes. They usually have a breaking strength of 8 tonnes and a working load of 2 tonnes.

My 1 is working load of 8 tonnes & breaking strain of 25 tonnes as it is 4 strand Marine Anchor rope :naughty :sly :naughty :thumbs
But

I just looked to check on my other strops (non kinetic) & they are all between 2.5 tonnes at 8 meters & 1.5 tonnes at 2 meters & starting off at 3 tonnes up to 8 tonnes working load so would guess your right :thumbs

Secondly, towballs ain't cast, they are forged. The smallest section on the ball is the neck below the ball, it's a little over 1sq.in in section which means it is many times as strong as your kinetic rope. Even if it were cast (which it isn't), it would still be way stronger.

I wouldn't particularly recommend using a towball for recovery, mainly because there isn't really a secure way of fixing the rope or a shackle to the towball, rather than because they aren't strong enough (which they are). The nightmare stories about towball failures during offroad recovery seem to come mainly from Australia, where it's quite common to use towballs that are on a threaded pin fixed through a rear bumper. Recovery using one of those obviously isn't on. EU type approved towballs ain't the same animal at all and are massively stronger. I would have thought that a combination ball/pin would be a better solution, though the pins often have a lower rating than the ball, sometimes only 2 tonnes.

Thats interesting to know :clap :thumbs

Just one last point before I whizz off on holiday (about 10 days before I see any more posts in this thread). The hole things shown on the photos at the start of this thread are lashing eyes not recovery points. My Patrol has these too and the handbook is VERY clear that they should not be used for recovery, as they are not strong enough. Recent Patrols have, as standard, a recovery eye welded onto a rectangular plate that fixes directly to the rear chassis cross member using 4 sizeable bolts. It is well above the towball and leaves plenty of clearance, even for an Alko stabilizer type caravan hitch. Maybe these are available for other Patrols too.



I understand that Mavericks and Terranos have similar lashing eyes at the rear and that many folks seem to use and recommend those for recovery. What does the original vehicle handbook say about that? I cannot understand how the lashing eyes on the rear of a Terrano can function any better as a recovery point than the similar (identical?) unsatisfactory lashing eyes on a Patrol.

Still ok to recover from as it is part of the chassis as long as its within reason in my opinion :nenau & better than a tow ball that can slip off as seen :thumbs
But where abouts have the tow bars been fitted :augie through or next to the lashing points :augie

Andrew

I think after all the evidence :lol a tow ball can be used to recover within reason & not as seen in the clip
Obviously a ball / pin would be better :thumbs
I cant see any harm in using the lashing points for recovery :nenau

I'm interested to see what Terranosaurus & extreme-4x4 have to say :nenau

 

[BongoBerry]

I'm interested to see what Terranosaurus & extreme-4x4 have to say :nenau

me too as it was one of their postings which identified the rear points as recovery ones

 

[Adz]

me too as it was one of their postings which identified the rear points as recovery ones

:thumbs :clap :augie :lol

Also have a look at this which rules out the 8 tonne breaking strain :augie

http://www.4x4recovery.com/Kinetic-ropes/Kinetic-Rope-8m-length/prod_15.html

 

[Adz]

http://www.towsure.com/category/7187-Towballs_and_Pins

 

[Thomas-the-Terrano2]

surely advantage of using towbar and coupling is it braces the load between the
chassis rails. if using the eyes then a bridle will be needed to spread load.

see plenty of hard core laners and trialers using a ball, in some cases mounted
on its back to form more of a hook to stop rope falling off.

surely shock recovery should be last resort, better to winch out steadily. certainly
winch wires should have a blanket over them to try to arrest the whiplash on
failure.

towing pure weight may be different to recovery, but then the coupling is designed
to keep outfit together when it goes wrong so in case of troll that could be 3500
kg bouncing around...

 

[Adz]

surely advantage of using towbar and coupling is it braces the load between the
chassis rails. if using the eyes then a bridle will be needed to spread load.


Like this for when i go off road only :thumbs

see plenty of hard core laners and trialers using a ball, in some cases mounted
on its back to form more of a hook to stop rope falling off.

surely shock recovery should be last resort, better to winch out steadily. certainly
winch wires should have a blanket over them to try to arrest the whiplash on
failure.

towing pure weight may be different to recovery, but then the coupling is designed
to keep outfit together when it goes wrong so in case of troll that could be 3500
kg bouncing around...

:thumbs

 

[BongoBerry]

duplicate

 

[BongoBerry]

http://www.towsure.com/category/7187-Towballs_and_Pins

see my first link...

 

[Adz]

see my first link...

2nd actually :augie :lol :lol :lol :thumbs
Great minds think alike :nenau
www.milneroffroad.com do em too :thumbs

 

[solarman216]

Anyone who has ever done any real recovery will know that you never ever snatch, that is the worst, especially in mud, you pull slowly and steadily to allow the mud suction to dissipate, I have pulled 43 ton mobile cranes from deep mud, and to snatch means to break, as for tow balls v lashing eyes, no contest tow ball every time, lashing eyes are what they are, for lashing on to a transporter, compare those with the recovery hook on the front of a Terrano, the only problem with tow balls is to stop the rope popping of and with a bit of thought that can be easily overcome, Rick

 

[Deleted account DD]

Well I dissagree a bit
The eyes/ recovery point where the tow bar bolts on to the chassis is mega strong (no idea in tonnage agreed) . It is a fixed point and not bolted on or anything:nenau so is designed for "recovery"
As long as reasonable precautions are taken when using kinetics I think they're a brill bit of kit

Agree :thumb2

A possible reason for "getting away" with massive loads like overcoming inertia caused by mud glue is the actual overall strength of the thing like you say.

Dont forget the 2.8tonnes or whatever is what the manf have arrived at as a maximum working load they guarantee the vehicle will be ok with. The actual strength of the vehicle structure will possibly be many times that.

Thinking back the way as a rough rule of thumb all structures on the aircraft I worked on were destruction tested to at least twice the expected max working load, cars trucks etc weren't a lot different that I was aware of.

If you think about it logically my vehicle via the tow bar is rated to pull 3.5 tonne or thereabouts which means within the limits of it I can hook up a trailer weighing just that.

However when you hit the road the forces and momentum that 3.5tonne load exerts will at times way exceed that figure on the tow bar. The 3.5 tonne is its max load, not its overall strength.

Therefore I would suggest that Adz is right that the normal tow bar will be fine for routine short term recovery and Pete is right that the structure on the back of the truck is even better.

That bloke is the video is a cock. If you use any piece of equipment wrongly it will break eventually. Thats even without being unlucky

We all learn our lessons I once saw a Bedford 4 tonner pulling a bogged down land rover (ours :augie:augie) out and the certified, strain tested chain as we used to use (being used properly n this occasion) snapped. It sort of focuses you :lol:lol

 

[makeitfit]

Well when I'm off roading the tow bar is off to allow extra clearance at the back for steep drop ins etc. So I still wont be using a ball to recover:lol
As for the kinetic rope, I still say it's bloody ace IF there's no winch available or convenient/safe access. Kinetic rope also allows similar weighted or powered trucks to use their inertia to get things pulled out. It works for me

 

[Adz]

Agree :thumb2

A possible reason for "getting away" with massive loads like overcoming inertia caused by mud glue is the actual overall strength of the thing like you say.

Dont forget the 2.8tonnes or whatever is what the manf have arrived at as a maximum working load they guarantee the vehicle will be ok with. The actual strength of the vehicle structure will possibly be many times that.

Thinking back the way as a rough rule of thumb all structures on the aircraft I worked on were destruction tested to at least twice the expected max working load, cars trucks etc weren't a lot different that I was aware of.

If you think about it logically my vehicle via the tow bar is rated to pull 3.5 tonne or thereabouts which means within the limits of it I can hook up a trailer weighing just that.

However when you hit the road the forces and momentum that 3.5tonne load exerts will at times way exceed that figure on the tow bar. The 3.5 tonne is its max load, not its overall strength.

Therefore I would suggest that Adz is right that the normal tow bar will be fine for routine short term recovery and Pete is right that the structure on the back of the truck is even better.

That bloke is the video is a cock. If you use any piece of equipment wrongly it will break eventually. Thats even without being unlucky

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We all learn our lessons I once saw a Bedford 4 tonner pulling a bogged down land rover (ours :augie:augie) out and the certified, strain tested chain as we used to use (being used properly n this occasion) snapped. It sort of focuses you :lol:lol

:thumbs :clap :augie We agree on something :lol :lol :lol
My only problem is engaging speech to typing :doh :augie :lol

Well when I'm off roading the tow bar is off to allow extra clearance at the back for steep drop ins etc. So I still wont be using a ball to recover:lol
As for the kinetic rope, I still say it's bloody ace IF there's no winch available or convenient/safe access. Kinetic rope also allows similar weighted or powered trucks to use their inertia to get things pulled out. It works for me

:clap :augie :thumbs

 

[(RIP) PLANK]

I allready got one (if i coudl have typed that in a french accent for all the python fans I would :lol)

I recon and im preapred to eb worng, but surely when using a rope or a stap, it should be the weakest part of the set up to make sure if somehting snaps it will be somehting soft?

Bear in mind that even the best pin hitches the pin is only rated at 3.5 tonnes, (though some 4 bolt fixing ones are five tonnes) These are usualy the more exspensive ones like dixon bate and suchlike, on cheaper ones the ball may be rated at 3.5 but the pin much less or even unrated! and on some cheapr ones the ball is only rated at 1500k!