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SteveC
03-07-12, 01:56 PM
Just picked up a 10,000 rated snatch strap from all places -- -Bunnings.

Looks good quality and I bought it as a spare as my original is over 5 years old.

Costs only $39.

DLE068
03-07-12, 04:33 PM
Is it white?

vk2icj
03-07-12, 08:04 PM
Hey Steve

I'd be thinking twice about using it in a heavy recovery for our "lighter" vehicles. A 10k strap needs a lot more force to stretch and load with potential energy than a 8k which then increases shock load on your recovery points. It starts to defeat the workings of the strap when you go to big. A GC doesn't have a chassis so you would want to minimize that shockload as much as possible,, (What straps are meant to do). Does it have a tag with a rating on it?


Chris

SteveC
03-07-12, 08:50 PM
hello Chris

I don't understand what you're saying. Though I thanks you for your comments

They're tested to 10,000kg breaking strength (minimum), and are capable of handling a 5000kg safe working load. Recommendation is 2-3 times gross weight of vehicle involved in the recovery. My vehicle is about 2000kg kerb weight. so it falls within the safe working range I would have thought, Not sure the weight of the JK for instance. Besides on heavy recovery I use an equalizer strap

ARB for instance have 3 straps starting at 8000kg up to 15000kg, so I think I should be safe and at a reasonable price. Though real use will tell one day!

I only have it as a spare for emergency.

Paul-JK
03-07-12, 11:40 PM
Hey Steve,

I think what Chris is saying is that it's the stretch in the strap that a) pulls you out and b) reduces the shock load on recovery points and chassis. So the more stretch the better.

If, for sake of argument, you managed to stretch an 8000kg strap to it's maximum during a recovery, a 10000kg strap might have only stretched to 80% of it's max in the same recovery and a 15000kg strap might have only stretched to 50% of it's max as they are both rated to pull far heavier vehicles. The 10000kg and 15000kg straps will therefore transfer more shock load to the vehicles as your relying more on strap strength then elasticity to pull the bogged vehicle out. It's not that the 10000kg or 15000kg won't do the job. They're more than capable of doing the job but that in itself becomes the problem. The increased shock loading caused by using the stronger straps will, over time, have the potential to damage the recovery points on the vehicles.

So, in short, you therefore want to use the lowest rated strap possible for a recovery to maximise the amount of stretch you get, as long as the strap is sufficiently rated of course.

Hope that makes sense.

vk2icj
03-07-12, 11:47 PM
Hi Steve,

Its not the strap failing I was worried about, but neither would I worry about a big 50K chain failing either,, but there is a reason we don't use chains anymore. Shock Load. Snatch straps work by stretching to take up the initial shock load (potential energy) and then when they reach no more than 20% stretch (unless they are past their safe use) they contract like a large rubber band and the Kinetic force placed on the vehicles is gradually increased until hopefully you pop free , hence you get a safer, softer recovery. If you have watched a number of recoveries you will see the strap literally stretch in length a considerable amount. That is why you don't use a snatch strap to winch with as you just load the strap with tons of potential energy (by stretching it) and then when you have ruined the strap it either breaks or you finally get unstuck at best you have taken all the stretch out of your strap and destroyed it lol,, but that is not what I was talking about. When you select a strap to big for the job it doesn't stretch as much if at all (haha) because not only does it have a higher breaking limit it also requires a higher amount of force to stretch it properly. So if you look at a 8k strap and compare it to a 10k you could assume that your vehicle takes 2k more force before the strap starts to work the way it was intended. Not a problem if you have a 5 ton F250 loaded or have a trailer. Back in the days of hooking up chains or some other non stretching recovery line (rope, cable) without the strap taking the initial shock load and spreading it out you got increased shock load at time of the strap tightening and thus a higher shock load at your recovery point. If you have ever been recovered this way you will KNOW the difference. You need the strap to stretch. Same reason you don't use a winch extension strap as a snatch strap on it's own. Vehicles without a chassis are more prone to damage because they just do not have the structural integrity that a frame offers when it comes to recoveries. If you bend your GC it's not as easy as straightening a ladder frame (and that aint all that ea$y either).

Cheers

Chris

vk2icj
03-07-12, 11:51 PM
So if you look at a 8k strap and compare it to a 10k you could assume that your vehicle takes 2k more force before the strap starts to work the way it was intended.




Probably a bit of an exaggeration but you get the idea. They do take considerably more force before they start to stretch.

SteveC
04-07-12, 12:38 PM
I hear what you are saying but Guys - but don't get confused between breaking rate and working rate.

reyzor
04-07-12, 01:07 PM
all straps have a SWL (safe working load) which is roughly 3-5 times LESS then the breaking strain of the strap......

these things have HUGE safety factors built into em

Wooders
05-07-12, 10:08 AM
My first preference would be for an 8000kg strap for appropriatness, but I don't think I'd have any major issue using a 10,000lb either.
On any unibody rig I'd really be trying to reduce the load of any heavy recovery anyway (ie dig a little).
But also keep in mind if it was a recovery from the rear using a tow hitch, and say pulling out a ladden land cruiser the 10,000lb strap would be prefectly accepatble in my mind. (Remember the V8 WJ like Steves is rated for towing 3,000kg)
So I guess, like always, it comes down to assessing the individual recovery situation and making an appropriate decision on the method & apparatus to use for THAT instance.

However very good point by chris, we should be mindful that a hiugher rated strap will have the "operating" (strecth) area at high load points thus putting more stress/shock on the mount.....and why a 30,000kg snap strap would not be a good idea for a Jeep ;)

dobbo56
05-07-12, 05:13 PM
that brings up a good point, my jk is only rated to tow 1600 kg, so is it safe to ,say do a recovery on a larger 4X4 weighing say 2.5 tons using the towbar mounted recovery hitch ????. id hate to rip the arse out of my little green Jeep.David D....

SteveC
05-07-12, 05:40 PM
Dobbo56 - your Jeep will run out of puff before it reaches the breaking limit of most straps (that are in good condition of course).
I don't know of any ones that sells a "quality" strap that is less than 8000kg breaking strain. So I see 10000kg gives me more of an advantage than not.
According to Just Straps, who have been around a long time:
It is very important the correctly rated strap is used. A strap with a ‘too light’ breaking strength may
break under load. A strap with ‘too heavy’ a breaking strength may not stretch properly and more stress
will be placed on the recovery points, possibly causing damage or injury. The Minimum Breaking
Strength (MBS) of the strap should be between 2 and 3 times the Gross Vehicle Mass (GVM) of the
‘lighter’ of the two vehicles used in the recovery process. Be aware that the Recovery Strap will be
under greater load if the vehicle is bogged in mud, sand or heavily loaded.

So what you guys are saying has some credence. for example,based on my calculations GVM 2.5T for my Grand, then a strap should be between 5000-7500kg. But I suppose you need to take into account the "extra weight when bogged" Oh bugger - I've bought one that may not work......oIIIIIIIo /\/\/\/\/\/\/\

dobbo56
05-07-12, 08:01 PM
i'm not worried about the strap breaking, i'm more concerned about ripping the rear crosmember out of my car. somthing for shorty owners to think about, i think ??.David D..

Paul-JK
05-07-12, 10:17 PM
i'm not worried about the strap breaking, i'm more concerned about ripping the rear crosmember out of my car. somthing for shorty owners to think about, i think ??.David D..

I'd guess if that's the case then getting recovery points on both sides connected directly to the chassis would be better than using your towbar. That way you can use an equaliser strap to spread the load more evenly between the chassis rails.

Why is the 2dr only rated to 1600kg when the 4dr is rated to 2300kg (which still isn't a huge amount anyway!)? The chassis will presumably be of the same construction and therefore you could assume a 2dr chassis strong enough to withstand 2300kg the same as the 4dr........probably!? The tow bar assembly itself will be rated to at least 2300kg as the same part will be used on 2drs and 4drs. What other factors determine towing capability?

Hunno
05-07-12, 10:47 PM
It's not the chassis in this case, it tow package installed that is the limiting factor. My ute is capable of towing 2300kg how ever the light duty bar installed is only rated to 1600kg. (Which is being changed & also requires a transmission cooler installed).

redrubi
05-07-12, 11:08 PM
The overall weight of your vehicle will determine safe weight you can tow, not just the power of your Jeep or rating of your bar or tow hitch .

Hunno
05-07-12, 11:19 PM
Maximum tow rating is set by the manufacturer, then other circumstances can limit even more.

Paul-JK
05-07-12, 11:34 PM
The overall weight of your vehicle will determine safe weight you can tow, not just the power of your Jeep or rating of your bar or tow hitch .

That's what I thought at first, and it would certainly make sense that a lighter vehicle shouldn't be able to tow as much, but then the shorty 150 Prado can tow more than the LWB. Admittedly the logic behind that seems backwards to me as there's no way a shorty should be allowed to tow more than a LWB equivalent.

I'm not surprised that the 2dr JK has a lower tow rating than the 4dr but I am surprised at how much lower it is. The 2dr is only 150Kg lighter than the 4dr (roughly 8% lighter) and only has a 10kg lower tongue load limit (roughly 6% lower) but the towing limit is 700kg less (or basically 30% less)......and it's not like the 4dr tow rating is that high to start with!

infoleather
27-07-12, 04:10 PM
They can do more work, but itself becomes a problem. Stronger strap will cause an increase in shock loading.