Be careful with recovery points.

Submitted: Monday, Apr 27, 2015 at 16:57
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This is where a mate of mines recovery hook hit my Nav. He was stuck in mud and I tried to snatch him out using a proper aftermarket hook which unbeknowns to me was only bolted on with one bolt as the other one was broken in his chassis. Glad it wasn't fatal. Before anyone bags me I am aware of the dangers in using tow balls etc and always try to do this stuff safely but! Note split above sticker and the door is also damaged enough that it won't shut properly. If it hit a person it could have made a mess. Luckily I'm in the process of making a canopy for it. Hope everyone had a good weekend.
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Reply By: Member - Kirk L - Monday, Apr 27, 2015 at 17:06

Monday, Apr 27, 2015 at 17:06
Sorry can't get photo to load.
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Reply By: Member - Kirk L - Monday, Apr 27, 2015 at 17:09

Monday, Apr 27, 2015 at 17:09
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Reply By: Member - Phil G (SA) - Monday, Apr 27, 2015 at 17:24

Monday, Apr 27, 2015 at 17:24
Thanks for posting this. Very sobering - a lot of near misses happen, and for many other reasons. You were very wise to have your vehicle in a forward direction so you were protected by the rear of the vehicle.
I'm a firm believer in using two recovery points for front recoveries - join them by an equaliser strap. That way you'll halve the load on each, and should a recovery point break, it will be restrained by the other side.
The next topic is dampeners - and unless a dampener has significant weight, it will not retard a broken point/shackle. I laugh when I see people put an empty bag over a strap.

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Follow Up By: Louwai - Tuesday, Apr 28, 2015 at 14:14

Tuesday, Apr 28, 2015 at 14:14
Phil,
I agree totally with spreading the load, but an equiliser strap can also be the instigator of an issue if not hooked up & used exactly the right way.

The equiliser will only put 50/50 load on each point if the "pull" is exactly in the middle & pulling exactly straight out in front. The slightest deviation from this will put more load on 1 point that the other.

The other issue is that a tow point is designed for direct straight pull out the front. By design, an equiliser strap puts a side-angle load "pull" onto the point. This can greatly weaken a tow point.
A typical equiliser strap is 2.5m long & most tow points are (approx) 1m apart depending on the vehicle.
So those dimensions almost create an equilateral triangle, which means the angle of load on each tow point is around 40 to 45deg off to the side.
That is a huge side-loading to be put onto a tow point that is designed for a direct straight front-on pull.

Taking into account the first coment above, If the pull was not central & straight, this would put even more side-load on a tow point & therefore put even more stress on it.

These comments are aimed at factory & aftermarket chassis mount tow points. Not purpose made bull-bar tow points..

Cheers, Bryan

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Follow Up By: Sigmund - Tuesday, Apr 28, 2015 at 17:05

Tuesday, Apr 28, 2015 at 17:05
Yeah. The factory says for mine that putting a bridle across only increases the rating by 50% over using one.
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Follow Up By: Member - Phil G (SA) - Tuesday, Apr 28, 2015 at 21:23

Tuesday, Apr 28, 2015 at 21:23
Gday Bryan, thanks for the good points you raised.
Pulling at an angle is an issue for any snatch recovery (with or without an equaliser strap). ARB give you warning stickers to never pull at an angle greater than the steering provides at full lock. I guess the message there is to turn the front wheels in the direction you are pulling.
As for the 50/50, the force applied will be equal ( an equaliser strap can't distribute forces unequally) but what is different is the angle on each recovery point. So the furtherest point will have a strap at a greater angle, so greater shearing forces will be applied to the bolts on that point. That is where the potential danger lies, and hence the problem with using an equaliser strap at a sharp angle. To attempt a heavy snatch recovery at a sharp angle to a vehicle stuck in mud is asking for trouble. Need a winch.

Equaliser straps come in different lengths and ratings - there is no standard!
A quick google found this:
Just Straps 2.5M and 4000kg
TJM 3M and 8000kg
Mean Mother 2.5M and 8000kg
Terrain Tamer 2.5M and 6000kg.

Also a tree trunk protector can also be used as an equaliser strap - they are usually between 3 and 5 metres long. I have both. It is what we were using 15 years ago - before equalisers became commercially available.

I measured the distance between front recovery points on the 200series - 830mm. If I were to use a 2.5M equaliser, the angle of pull is 72 degrees instead of 90 degrees. If I use a 5M long equaliser, the angle is 80 degrees. Like Sigmund says the rating needs to be reduced, but will depend on the strap length.

But the other important function of the equaliser is to retain the lethal missile that is released if a recovery point breaks.
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Reply By: Mick O - Monday, Apr 27, 2015 at 18:53

Monday, Apr 27, 2015 at 18:53
Strewth...you'd have someones eye out with that!

Those captive nuts in the chassis can be a real trap ads I found out cracking a couple in the front chassis of my Navara a few years back. Thanks for posting. Very sobering.

Cheers

Mick
''We knew from the experience of well-known travelers that the
trip would doubtless be attended with much hardship.''
Richard Maurice - 1903

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Follow Up By: Member - Kirk L - Monday, Apr 27, 2015 at 19:06

Monday, Apr 27, 2015 at 19:06
Dead right mick. I lost front point on Nav on Easter weekend. The two bolts just pulled out of those nuts on chassis leaving threads behind. Still working out what I can do with that. Thought about putting bolts right through chassis with nuts but think chassis rails will just squash when bolts are tightened. Maybe fabricate a bracket that doubles the rail. Pretty scary.
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Follow Up By: Member - bungarra (WA) - Monday, Apr 27, 2015 at 19:34

Monday, Apr 27, 2015 at 19:34
Kirk

If you decide to bolt right through the chassis you can insert a tubular spacer the exact length of the INSIDE dimensions ( actually the exact length of outside to inside) of the chassis rail so the bolt goes through the centre of this....

Obviously you need to drill an over size hole from either the top or bottom of the chassis to insert the spacer and add a washer prior to bolt / nut but at least that way you can excerpt full tension without compressing the chassis rail

appologies if I'm suggesting something you already thought of

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Follow Up By: Member - Kirk L - Monday, Apr 27, 2015 at 19:53

Monday, Apr 27, 2015 at 19:53
Thanks mate. I know about doing that stuff but hadn't thought of it and not sure if I can get a spacer in but that will be taken into consideration when I do repairs. Cheers
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Follow Up By: Member - Phil G (SA) - Monday, Apr 27, 2015 at 20:03

Monday, Apr 27, 2015 at 20:03
Kirk, If the bolt pulled through, it is most likely that an imperial fine thread bolt has been used instead of the correct metric 12x1.25 that I expect is required for the Navara. Seen it happen before.
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Follow Up By: Member - Phil G (SA) - Monday, Apr 27, 2015 at 20:34

Monday, Apr 27, 2015 at 20:34
Here's a link to a similar discussion from 2008 but with 80series Landcruiser: LINK HERE

Many lessons from all this, but if you want to make snatch recovery safer, at very least you need an equaliser strap on 2 points and if a heavy snatch is required, a heavy dampener on the strap.

One of the stupid things I think is that aftermarket recovery points are very, very heavy and often recommend the bigger 4.7T shackles. In my opinion, bigger is not better in this situation. No point in having these bits stronger than the bolts and the chassis they are bolted in to.
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Follow Up By: Member - Kirk L - Tuesday, Apr 28, 2015 at 06:40

Tuesday, Apr 28, 2015 at 06:40
Phil the ones that pulled out of my Nav were the original factory ones. The bolts came out stripped.
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Reply By: 671 - Monday, Apr 27, 2015 at 20:07

Monday, Apr 27, 2015 at 20:07
I wonder why the other bolt had broken. Chances are it was due to who knows how many previous snatches.

The internet is full of examples of broken hooks or bolts which is not surprising because the things have not been designed for snatch straps. Car manufacturers call them towing hooks. Aftermarket hooks are also labeled towing only.

The forces generated by snatch straps can be, and usually are, well above the levels reached in towing.

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Reply By: Crusier 91 - Tuesday, Apr 28, 2015 at 07:09

Tuesday, Apr 28, 2015 at 07:09
Also covered here in 2008

http://www.offroad80s.com/warning-recovery-points-attached-to-chassis-captive-nuts-t2005.html
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Reply By: Member Kerry W (WA) - Tuesday, Apr 28, 2015 at 12:38

Tuesday, Apr 28, 2015 at 12:38
Just another option to consider when recovering a vehicle. Most times (in my experience) the vehicle to be recovered just needs a "bit" of help to get moving again. I often see recoveries overdone. Too much speed, to much stretch and too much haste. I know sometimes the recovering vehicle may only be marginally moving or not set up very well, (limited capability) so its best not to take any chances of getting 2 vehicles bogged.
Most of the recoveries I have done over the last 15 years or so I have done gently with a chain and have only put enough grunt in as necessary. The ones which required snatching really needed momentum. Yes, I always check the other vehicles recovery point (if it has one....)

(I also work underground and often am involved in recoveries involving buried remote controlled boggers (loaders), most times this involves several hundred tonnes of loaded UG Dump trucks jerking on a massive cable to free the partially buried machine. It worth noting that I have seen a steel sling weighing over a tonne flung backwards 30m when an attachment has broken - so I advise much caution with chain as well - dont jerk it!)


My point here is only to get others to think about how hard we really need to go when recovering and does the other vehicle really need a high energy snatch.
Originally I started using a chain to save my own snatch straps as many vehicles we came across had little or no recovery gear at all.
A good quality hi tensile (Herc Alloy or similar) chain used in a steady pull does not stretch and will not fly back at you. (unless you jerk it hard enough to break something).

Not preaching - just putting a different idea out there for people to consider.

hope it helps save somebody some grief somewhere down the track...
Kerry W (Qld)
Security is mostly a superstition. It doesnt exist in nature. Life is either a daring adventure or nothing.
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Follow Up By: Parso - Wednesday, Apr 29, 2015 at 21:36

Wednesday, Apr 29, 2015 at 21:36
Hear, hear, Kerry!
Parso
2012 Toyota Landcruiser 200 Series Sahara.

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