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7th April 2011, 10:33 PM
#21
Patrol God
My understanding of dampner is to slow the strap from whipping back to the "watcher" even when he is at safe distance doing the calling. And yes I ahve also heard of placing on on each end near the recovery points to increaese some resistance in air to make it fall when things go wrong.
And BTW, I do think Growlers recovery was done very well.
Tim
Getting Older Is Unavoidable, Growing Up Is Optional!
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7th April 2011 10:33 PM
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8th April 2011, 12:07 AM
#22
Patrol God
Originally Posted by
the evil twin
At the risk of inciting a riot...
The "damper" mechanics or physics if you prefer are different between a Winch Cable and a Snatchie so I believe what applies to one doesn't necessarily appply to the other.
The damper on a winch cable is to defuse the energy in the cable if a point fails or the longer section of cable if the cable snaps. The ability of the cable to release the energy is a slow process compared to a snatch strap and the entanglement of the damper and intrinsic weight of the cable also get it onto the ground pretty quick.
Snatchies have the slingshot effect and by design are extremely efficient at transferring force to the end of the strap. When a point fails the energy is transferred VERY quickly into what ever object is left on the Snatch Strap. That is why it is MUCH more preferable NOT to use shackles in a snatch recovery. Hook style recovery points or similar are the go if you have them, still bl00dy dangerous tho.
IMHO a Snatch Recovery has heaps more potential danger than winching because the efficiency of damping is significantly less. Lets say a shackle and recovery plate rip out of a vehicle for whatever reason. That lump of metal is going to depart with maximum energy and acceleration and the damper will have no effect until the object has flown past the damper and taken up the slack which is usually about the same time it arrives at the other vehicle so a damper in the middle of the cable doesn't provide a terrible lot of protection.
Another consideration is this. The weight of any damper lying on the ground near the centre of the strap will be flung upwards as the strap takes up. So at the moment of maximum force when the system is liable to fail the weight of the damper is negated as it is still heading skywards.
Sooooo (dare I say it) in light Snatch recoveries I do not necessarily use a damper (I can hear the intake of breath already) BUT in heavy ones I advocate the use of two. One at each end close to the vehicles. 1/4 filled sand bags are perfect
not trying to sound to fussy but.................one should not place a line damper on the middle of a snatch strap, that is totally usless and takes the sting out of the strap on recovery.
but place a line damper on one third of either end, using two line dampers on a snatch recovery should be in my humble opinion the mandatory way to do this sort of recovery , if the strap should break either end you have some form of back up.
putting a "s" in the strap will assist in stopping knots and debris pick up ,and keep the strap flat, no twists in the strap at all, and DONOT use a bridal in snatch recovery .
i have done a few recoveries using this method and it work`s fine
last but not least as Evil says absolutly NO shackles should be used in a snatch recovery AT ALL, thats a quick way to die .............
HELL NO !!!!!!
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8th April 2011, 12:31 AM
#23
Expert
Originally Posted by
nowoolies
last but not least as Evil says absolutly NO shackles should be used in a snatch recovery AT ALL, thats a quick way to die .............
So am I better off installing recovery hooks rather than points?
An awful lot of people have installed recovery points that require the use of shackles to secure the snatch strap to the vehicle, which I thought was acceptable?
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8th April 2011, 12:51 AM
#24
Patrol God
Originally Posted by
GUte
So am I better off installing recovery hooks rather than points?
An awful lot of people have installed recovery points that require the use of shackles to secure the snatch strap to the vehicle, which I thought was acceptable?
no i would not use a recovery hook at all, slight bit of slack on the strap and it falls off .
i have shackles both ends of my bus but if im doing a snatch recovery they come off before i start
always snatch from the rear
use your locking pin that holds your towball in place
take out the tow point, and insert the loop off the strap and replace the pin , through the tow hitch and through the loop off the strap
then your ready to start
on the vehicle thats to be recovered i put the strap through the bull bar down low , or around the bull bar ,for front on recovery.
before attaching to the vehicle thats doing the recovery ,
or if as mostly done, use the tow point of the other vehicle , the same way as setting up on the recovery vehicle , as most recovery seems to be pulling backwards , and dont forget your line dampers x 2 one either end i set them at approx one third off both vehicles.
hope this makes some sorta sence
Last edited by nowoolies; 8th April 2011 at 01:10 AM.
HELL NO !!!!!!
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8th April 2011, 02:03 AM
#25
RIP - valued member and true gentleman of this forum that will be missed by many!
I've seen the 'Barefoot Bushman' completely remove an alloy bullbar from a bogged hilux with a snatch strap - on TV of course.
I wonder if the issue is really that we have all gone from 2000kg straps, to 4,000, then 6,000 and now I believe they can be obtained at 12,000.
In some ways I'd rather break a weaker strap then have a stronger one, say the 12 tonner, or maybe one of the others, reef a recovery point out, or a bull bar off, and then launch it at the tow vehicle. I'm sure being belted with the nylon strap would be pretty damaging, but a lot less than a chunk of metal as well
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8th April 2011, 11:23 AM
#26
I am he, fear me
Originally Posted by
Silver
I've seen the 'Barefoot Bushman' completely remove an alloy bullbar from a bogged hilux with a snatch strap - on TV of course.
I wonder if the issue is really that we have all gone from 2000kg straps, to 4,000, then 6,000 and now I believe they can be obtained at 12,000.
In some ways I'd rather break a weaker strap then have a stronger one, say the 12 tonner, or maybe one of the others, reef a recovery point out, or a bull bar off, and then launch it at the tow vehicle. I'm sure being belted with the nylon strap would be pretty damaging, but a lot less than a chunk of metal as well
Yep... they sure are an efficient force multiplier aren't they.
and... totally agree that the sizes available lead to issues as well so just an FYI for anyone who wasn't aware...
The snatch strap rating should be no more then 3 times the weight of the lighter vehicle (not necessarily the bogged one... unless that is the lighter one). So in the case of Dogman who likes getting recovered by Suzuki's a 2,000Kg is prob what he should carry.
Anyway, apart from Doggydude, the rest of us should prob have a 6 or 8 K strap as just like you I would MUCH rather a strap break than re-invent the concept of field artillery.
Dolphins are so smart that within a few weeks of captivity, they can train people to stand on the very edge of the pool and throw them fish.
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The Following 3 Users Say Thank You to the evil twin For This Useful Post:
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8th April 2011, 11:59 AM
#27
I am he, fear me
There will be 101 differing opinions on recoveries and I don't get bent out of shape about anyone elses opinions to much. The bottom line becomes if both parties are happy then that is the method to go with. If one party isn't then reassess the rigging.
As I stated, my OPINION for snatchies is...
First, Use the snatch as a last option as it is the most intrinsically dangerous.
Second, ALWAYS, ESPECIALLY if in Mud or anything that has a significant suction effect, spend a little bit of sweat to dig out at least some of the material that has mired the vehicle, just a couple of spade fulls from in front of the wheels will break the suction and/or ease the path greatly reduce the forces required. Actually that is a pet hate of mine when people won't 'prep' the mired vehicle properly for a recovery and just jump out and strap on a rope/winch/snatchie.
If you choose to use a snatch as the recovery method
Hooks not shackles if at all possible and absolute minimum of metal bits in the rigging. If you think the strap will fall off a bit of string, eleccy wire, even a rubber band can be used to mouse it onto the hook
Inspect the strap as you lay it out, no twists, start with one small "S" of about 1 metre, increase if required if the first attempt fails.
Two dampers no more than 1/3rd the distance from the vehicles but the closer to the vehicle the better
If you use a bridle attach it as you would if joining two straps
Avoid using a Bullbar as an attachement point unless an absolute last resort. (It was what, less than 6 months, since that girl was killed in Qld when the Bar let go during a snatch)
Consider raising the bonnet on any vehicle facing the strap if its a gnarly recovery
Now many people may disagree with the above and thats cool (and there are other things like getting bystanders away blah blah)... but, like I said, the above is what makes me comfy. If it doesn't work for others then no worries. Bottom line is if I am not happy with your method I won't do it and I offer others the same rights no questions about it
Dolphins are so smart that within a few weeks of captivity, they can train people to stand on the very edge of the pool and throw them fish.
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The Following 5 Users Say Thank You to the evil twin For This Useful Post:
AB (8th April 2011), DX grunt (8th April 2011), Finly Owner (8th April 2011), MudRunnerTD (9th April 2011), rkinsey (8th April 2011)
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8th April 2011, 02:30 PM
#28
Administrator
Good idea with the bonnet up too!
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8th April 2011, 02:36 PM
#29
Enjoying the trips
Originally Posted by
AB
Good idea with the bonnet up too!
agree as well!!
Evil great to mention that, took some new club members through our pre trip training they have to do a few weeks ago, they were very much in favour of the "bonnet up" when told of what can go wrong.
Good call
Macca
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8th April 2011, 02:52 PM
#30
RIP - valued member and true gentleman of this forum that will be missed by many!
The bloke who ran the course we did at Kooralbyn looped his bridle from recovery point to recovery point, it had some old 2 1/8" fire hose ok ok 68mm, :-) running loose in the centre to protect the bridle - he ensured it was under the looped end of the snatch strap - ie, in the centre of the bridle.
I think I'll be looking for a webbing bridle, as the thought of my current couple of metres of 10mm graded chain flying through the air is a bit disconcerting.
However, I first need to get a second recovery point for my GQ - had two at each end on my old MQ.
Agree 110% with putting sufficient thought, then preparation into a recovery before getting into action with straps or winches. When one uses a hand winch, as I do, less time on the handle is good!
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