doubling up your snatch strap

[sladey]

does doubling up your snatch strap double the amount of force needed before its stretches? ie: is it a good idea to double it up? interested in peoples thoughts as i am sure it has been an issue for some people at some point?

[Abraxix]

only reason i've ever needed to double up a snatch is when towing a car, yes i know shouldnt' use a snatch however with it doubled back to the tow car there is not as much "flex" / "stretch" in the strap..

however i don't believe it double the force or anything to that effect as it still loops around the lead / back car with one attachment point, and from what i would have thought it is rated to the weight in which you're pulling if you double it over you would be creating a weak point where it loops around the lead / tow car

at least those are my thoughts.. would be interested in knowing someone who can number cruntch and do the physics on this!!!

[timbotrog]

I fully understand what you are getting at, and you are correct.

Even though the strap is connected to a single point is has 2 "falls" of the strap meaninig each has its own strength. So if it's a 9000t strap in what you describe it will become a 18000t strap, and yes the shackle would give way before the strap does. it is the same as using a "snatch" block with a winch cable or rope.

It's the same as the difference between the 1t and 2t chain motors we use in concert lighting to lift trusses into the air.
With the 1t chain motor the chain is connected to a hook at one end and the chain motor "climbs" up and down the chain, whereas with a 2t chain motor it is the same grade of chain but as opposed to having a hook on the bottom of the chain it runs through somthing akin to a snatch block and reconnects to the bottom of the chain motor. In other words the chain loops down and back up with the "hook" at the bottom of the loop. The extra weight in the 2t chain motor is due to having twice as much chain than a 1t motor.

http://www.ausjeepoffroad.com/forum/...6&d=1367452347

http://www.ausjeepoffroad.com/forum/...1&d=1367452368

[Dustbowl]

Timbotrog, spot on explaination

In a moment of stupidity I Busted my front recovery hook off and learned the hard way...

[phaqnhell]

Dunno if I'm reading this right, but do you mean doubling up to get extra length?
I would've thought doubling up would only increase in strength if they are parallel?
Just going by what I've seen cranes do

I'm interested to know as this situation arises quite often

[SeaComms]

I think he means doubling up as in folding in half, half the length / twice the strength.

My 2c worth.

If you ran two separate straps then yes, I would say the strength has been doubled and the elasticity halved or thereabouts. Problem is the halved elasticity will make them quite stiff and more like using a winch extension strap than a snatch strap.

However, doubling up a single strap will not be the same as two seperate straps at each end, as one end (the middle of the strap) is only one piece of strap wrapped over a loop and I would think this would be the weak point. I know with lifting slings they show a basket lift (so strap goes down and around the object and back up to the hook again) does double the lifting capacity of the sling, but I cant find any info on completely folding the strap in half.

This single layer of strap over a D link or similar is still taking the entire load as far as I can see, whereas the two points attached at the other vehicle are taking half the load each. Just my thoughts, could be wrong! However, if its doubled up through the rounded side of a D shackle causing the strap to curve and not sit flat then this will definately weaken the strap at this point.

[sladey]

Originally Posted by SeaComms

I think he means doubling up as in folding in half, half the length / twice the strength.

My 2c worth.

If you ran two separate straps then yes, I would say the strength has been doubled and the elasticity halved or thereabouts. Problem is the halved elasticity will make them quite stiff and more like using a winch extension strap than a snatch strap.

However, doubling up a single strap will not be the same as two seperate straps at each end, as one end (the middle of the strap) is only one piece of strap wrapped over a loop and I would think this would be the weak point. I know with lifting slings they show a basket lift (so strap goes down and around the object and back up to the hook again) does double the lifting capacity of the sling, but I cant find any info on completely folding the strap in half.

This single layer of strap over a D link or similar is still taking the entire load as far as I can see, whereas the two points attached at the other vehicle are taking half the load each. Just my thoughts, could be wrong! However, if its doubled up through the rounded side of a D shackle causing the strap to curve and not sit flat then this will definately weaken the strap at this point.

yea, spot on im talking about situations where the space to snatch is limted and you have to fold the snatchy in half, back to the car your snatching out, figured it would double its rating and cause shackles to be under more jerking force before the stretch happens,, if that makes sense