Soft shackles and kinetic ropes

[ToyodaAddict1980]

Ive been using factor 55 hitch links with soft shackles. I take it that edge is probably to sharp and I should be using a steel shackle? I feel weird about hooking a steel shackle to the aluminum hitch. The hitch would become the weak link?
3/4'' steel shackle minimum breaking load 57,000
factor 55 link 51,000
7/8'' rope 28,600 and 3/4 rope 19,000


So far I've only been using this stuff for little bumps. On the rare occasion something is really stuck, we winch.

Back in the day we used chains , cables, and worn out straps rejected from the job site
I'm trying to do better now

 

[AgitatedPancake]

Just for some context of more desireable soft shackle hitch attachment points, check out Brennan's offerings.

Soft Shackle Receiver Adapter, 2.0 size

The soft shackle wraps around a boss that enlarges the radius of the hitch pin itself, then the "mouth" is the softest radius possible within the dimensional constraints. Just an effort to make the softest pressure points possible. Super clean product design . I don't have one yet, but definitely on my radar.

(He applies the same concept making radii as large as possible to fairleads and recovery rings as well, anywhere synthetic line is used)
Winch 'HOSS' Hawse Fairlead
Recovery Ring Package

 

[CarterKraft]

The brackets on that bumper appear woefully undersized, like slide rule chart were used for tensile strength of plate steel instead of a safety factor of 5x static.

 

[Mieser]

Just for some context of more desireable soft shackle hitch attachment points, check out Brennan's offerings.

Soft Shackle Receiver Adapter, 2.0 size

The soft shackle wraps around a boss that enlarges the radius of the hitch pin itself, then the "mouth" is the softest radius possible within the dimensional constraints. Just an effort to make the softest pressure points possible. Super clean product design . I don't have one yet, but definitely on my radar.

Thank you for the mention! I tried to make the best possible 2.0 and 2.5 Soft Shackle Receiver Adapter I could.

Soft Shackle Receiver Adapter, 2.0 size

This 5-axis machined 6061-T6 billet aluminum masterpiece provides the perfect connection for soft rigging into a 2.0" receiver hitch. The SSRA ( Soft Shackle Receiver Adapter) from Brennan's Garage provides the safest, most direct, connection to the pin in a common receiver hitch while using...

brennans-garage.com

Soft Shackle Reciever Adapter, 2.5 Size

This 5-axis machined 6061-T6 billet aluminum masterpiece provides the perfect connection for soft rigging into a 2.5" receiver hitch. The SSRA ( Soft Shackle Receiver Adapter) from Brennan's Garage provides the safest, most direct, connection to the pin in a common receiver hitch while using...

brennans-garage.com

 

[AgitatedPancake]

Thank you for the mention! I tried to make the best possible 2.0 and 2.5 Soft Shackle Receiver Adapter I could.

Soft Shackle Receiver Adapter, 2.0 size

This 5-axis machined 6061-T6 billet aluminum masterpiece provides the perfect connection for soft rigging into a 2.0" receiver hitch. The SSRA ( Soft Shackle Receiver Adapter) from Brennan's Garage provides the safest, most direct, connection to the pin in a common receiver hitch while using...

brennans-garage.com

Soft Shackle Reciever Adapter, 2.5 Size

This 5-axis machined 6061-T6 billet aluminum masterpiece provides the perfect connection for soft rigging into a 2.5" receiver hitch. The SSRA ( Soft Shackle Receiver Adapter) from Brennan's Garage provides the safest, most direct, connection to the pin in a common receiver hitch while using...

brennans-garage.com

No problem at all man. I wasn't sure if you were hesitant to bring them up, but they definitely seem worth sharing here!

 

[Mieser]

No problem at all man. I wasn't sure if you were hesitant to bring them up, but they definitely seem worth sharing here!

I try not to push too much. I just make things that I want to run and let the rest take care of itself.
I'm mostly just here to try and give good technical info.....that gets me in enough trouble as of late.

 

[Clb]

I

Just for some context of more desireable soft shackle hitch attachment points, check out Brennan's offerings.

Soft Shackle Receiver Adapter, 2.0 size

The soft shackle wraps around a boss that enlarges the radius of the hitch pin itself, then the "mouth" is the softest radius possible within the dimensional constraints. Just an effort to make the softest pressure points possible. Super clean product design . I don't have one yet, but definitely on my radar.

(He applies the same concept making radii as large as possible to fairleads and recovery rings as well, anywhere synthetic line is used)
Winch 'HOSS' Hawse Fairlead
Recovery Ring Package

Now that's purty
curious as to the 1.5
2.5
3x
rope diameter quotations I keep seeing used but still not finding any mfg that has a # listed yet...
time to hit that site..

eta
looks like 1.5 is how that one is engineered...

 

[Clb]

I try not to push too much. I just make things that I want to run and let the rest take care of itself.
I'm mostly just here to try and give good technical info.....that gets me in enough trouble as of late.

new hero status achieved,

Sorry if this gets you buried in questions.

 

[2big bronco]

Ok, the fact that you didnt actually tear open your neck is pretty damn funny. I had my wife rush me to the er with my hand wrapped in a bloddy sock and I was sure it was bairly hanging on my a thread. It ended up being a smallish cut about 1/4" deep. My shock turned to instant embarrassment. 😐

 

[Mieser]

I

Now that's purty
curious as to the 1.5
2.5
3x
rope diameter quotations I keep seeing used but still not finding any mfg that has a # listed yet...
time to hit that site..

eta
looks like 1.5 is how that one is engineered...

The geometry of the 2.0 version of the SSRA ( Soft Shackle Receiver Adapter or SaRAh device) is driven by the available space inside the 2.0 hitch. It was the best compromise for overall strength vs soft shackle size. The 2.5 version is a bit larger and features even better performance, but is still going to have the same 5/8 pin. Both of these units are a good match for the 45500lb 7/16" based soft shackle included in my kits. The limiting factor in the system becomes the hitch and hitch pin. It isn't very common to shear even a decent quality 5/8 pin as long as it is well supported. A great quality pin or a properly shanked grade 8 bolt will do in the neighborhood of 60klbs before failure. Most hitch assemblies are going to show major tearing in the pin holes or deformation in the cross tube way before any of those loads.

 

[Clb]

Thank you for the information.
Good stuff.

 

[elbekko]

Watching some heavy recovery stuff made me think. The rim slings they use are pretty much the same material as a soft shackle (a fair bit bigger rope dia though), and they're used all the time around sharp edges, with the only protection being their sleeve: Synthetic Lifting & Recovery Sling | RimSling

How are these not failing all the time when getting pinched in a wheel like this?

 

[white-rhino]

Not a heavy load with a running start.

 

[ApeEater]

Watching some heavy recovery stuff made me think. The rim slings they use are pretty much the same material as a soft shackle (a fair bit bigger rope dia though), and they're used all the time around sharp edges, with the only protection being their sleeve: Synthetic Lifting & Recovery Sling | RimSling

How are these not failing all the time when getting pinched in a wheel like this?

Not a heavy load with a running start.

This. It's essentially a static load, and it's a pretty light load at that.


Did anyone ever do the math on the force behind the Jeep that was pulling him out?

 

[Winchested]

Watching some heavy recovery stuff made me think. The rim slings they use are pretty much the same material as a soft shackle (a fair bit bigger rope dia though), and they're used all the time around sharp edges, with the only protection being their sleeve: Synthetic Lifting & Recovery Sling | RimSling

How are these not failing all the time when getting pinched in a wheel like this?

There's a huge difference between a static and a dynamic load. Plenty of us having been saying this from the start.

Also from a "real" rigging standpoint a Bow shackle (what you all are calling D shackles that aren't even in the shape of a fucking D) is only rated for up to 60 degrees pull angle or lift angle.

KNOTS, in rigging or soft shackles or rope decrease its rating by 25% instantly. A choker is a 25% decrease instantly.

 

[Mieser]

Watching some heavy recovery stuff made me think. The rim slings they use are pretty much the same material as a soft shackle (a fair bit bigger rope dia though), and they're used all the time around sharp edges, with the only protection being their sleeve: Synthetic Lifting & Recovery Sling | RimSling

How are these not failing all the time when getting pinched in a wheel like this?

They are going to see accelerated wear and decreased strength pulling over hard edges, they are just basically 'ignoring' it and taking a FoS approach similar to overhead lifting slings. All overhead lifting slings will also give you warnings about pulling over hard edges....round or flat. Even steel cable slings have that same warning. Some people just choose to ignore it.

Looking at their ratings, 3/8 SK-75 Dyneema would have a MBS of 17,600lbs and an ABS of 19,600lbs. They are giving it a 3500lb vertical ( point to point ) 'rating'......so almost exactly 5:1 from the MBS.....

 

[Mieser]

Did anyone ever do the math on the force behind the Jeep that was pulling him out?

I tried to do some Time-Distance stuff to determine the vehicle speed.....I came up with 10-12mph.
We would be talking in the neighborhood of 4-5x the vehicle weight in Kinetic Energy.
Seeing how that rope behaved, we would also have to add something for the short 'impulse', but that is a bit harder to quantify.

Rough numbers.....probably 20,000 to 30,000lbs if the vehicle was close to 5000lbs.

 

[RPS1030]

Watching some heavy recovery stuff made me think. The rim slings they use are pretty much the same material as a soft shackle (a fair bit bigger rope dia though), and they're used all the time around sharp edges, with the only protection being their sleeve: Synthetic Lifting & Recovery Sling | RimSling

How are these not failing all the time when getting pinched in a wheel like this?

It’s also a sling with buried eyes vs the knot/noose/multiple line of a soft shackle

 

[ApeEater]

I tried to do some Time-Distance stuff to determine the vehicle speed.....I came up with 10-12mph.
We would be talking in the neighborhood of 4-5x the vehicle weight in Kinetic Energy.
Seeing how that rope behaved, we would also have to add something for the short 'impulse', but that is a bit harder to quantify.

Rough numbers.....probably 20,000 to 30,000lbs if the vehicle was close to 5000lbs.

vehicle weight (lbs)	speed (mph)	force (ft/lb)
5000​	10​	16712​
5000​	11​	20221​
5000​	12​	24065​

 

[Clb]

Now we're getting a real good look at the #'s thanx guys

Just watched a vid that said 5 and 8 times the diameter for bend radius.
This was going thru/around winch rings tho

 

[Mieser]

vehicle weight (lbs)	speed (mph)	force (ft/lb)
5000​	10​	16712​
5000​	11​	20221​
5000​	12​	24065​

Kinetic Energy alone does not take into account the time of the 'stop', I refer to this as 'impulse'. In this case, the larger 1" rope didn't show a lot of apparent stretch during the event......so it would be a 'shorter' impulse which would impart even more force to the anchor. Can we quantify exactly what that is going to be without testing, probably not.

 

[arse_sidewards]

Kinetic Energy alone does not take into account the time of the 'stop', I refer to this as 'impulse'. In this case, the larger 1" rope didn't show a lot of apparent stretch during the event......so it would be a 'shorter' impulse which would impart even more force to the anchor. Can we quantify exactly what that is going to be without testing, probably not.

The word you're looking for is "acceleration"

There's even a really handy dandy formula for calculating it.

 

[ApeEater]

Kinetic Energy alone does not take into account the time of the 'stop', I refer to this as 'impulse'. In this case, the larger 1" rope didn't show a lot of apparent stretch during the event......so it would be a 'shorter' impulse which would impart even more force to the anchor. Can we quantify exactly what that is going to be without testing, probably not.

agreed.

I am taking lessons from this thread though. I'm preparing a recovery class for a veterans offroad event in may, and I'll definitely be talking about the forces involved with kinetic ropes.

 

[Mieser]

Now we're getting a real good look at the #'s thanx guys

Just watched a vid that said 5 and 8 times the diameter for bend radius.
This was going thru/around winch rings tho

Good rope manufacturers like Samson have all these guidelines posted in their supporting information

The word you're looking for is "acceleration"

There's even a really handy dandy formula for calculating it.

Still need to know the change in TIME of the 'acceleration' event, which we don't smartass.

 

[arse_sidewards]

Still need to know the change in TIME of the 'acceleration' event, which we don't smartass.

Well we know it wasn't long enough

 

[Mieser]

Well we know it wasn't long enough

Correct!

 

[JR4X]

Also from a "real" rigging standpoint a Bow shackle (what you all are calling D shackles that aren't even in the shape of a fucking D) is only rated for up to 60 degrees pull angle or lift angle.

Might be the same case in marketing as Orbitrol valves getting renamed to Orbital or orbit valve and the entire industry running with it.

You’re splitting hairs here when everyone who sells a shackle lists it as a D and not anywhere in their literature call it a fucking “bow shackle”.

If I need a steering valve I go buy a brand new orbital and if I need new clevices I go buy brand new “D ring shackles” because I want the path of least resistance to the product I want. If you walk into a store and ask for bow shackle (because you don’t value your time and you like to be a Dick) I guarantee you’re looking for the oldest guy in there before you speak.

 

['84 Bronco II]

If I need a steering valve I go buy a brand new orbital and if I need new clevices I go buy brand new “D ring shackles” because I want the path of least resistance to the product I want. If you walk into a store and ask for bow shackle (because you don’t value your time and you like to be a Dick) I guarantee you’re looking for the oldest guy in there before you speak.

To be fair, you are looking at off road industry junk that wouldn't pass muster at a job site (at least where I work). Anyone working in the craning and rigging industry knows the difference between a D-ring and Bow shackle. One can tolerate side loading to an extent and the other cannot.

 

[Beat95yj]

Still need to know the change in TIME of the 'acceleration' event, which we don't smartass.

You were able to figure out the velocity of the vehicle. To figure out time maybe you could use a high tech tool like this-

 

[arse_sidewards]

One can tolerate side loading to an extent and the other cannot.

When was the last time anyone even in the rigging industry ever bought a D-ring that wasn't technically a bow shackle?

My impression was that all those minor variations of rigging hardware mostly died out when machines replaced blacksmiths except in the really huge marine industry shit where the difference between a D-ring and a bow shackle is potentially a few hundred pounds of material.