Soft shackles and kinetic ropes

[ApeEater]

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-

I mean you'd have to figure out time to figure out velocity in the first place.

 

[arse_sidewards]

To be fair, you are looking at off road industry junk that wouldn't pass muster at a job site

Fine them have it your way.

 

[Mieser]

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-

If you think you are that fast, go for it. You know we are probably talking tenths of a second to figure out impulse.

 

[2big bronco]

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.

Ive been working as an ironworker for 22years and am a "certified rigger" for what thats worth.... and have never heard of a bow shackle before this thread

 

[Beat95yj]

If you think you are that fast, go for it. You know we are probably talking tenths of a second to figure out impulse.

Should be no problem with a manual stopwatch. Possibly a bit more challenging with a sundial.

 

[Beat95yj]

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.

Cool, since you’re educating us which is which?

 

[Mieser]

Should be no problem with a manual stopwatch. Possibly a bit more challenging with a sundial.

Bullpucky. Plug it into a calc and post up your guess then.

 

[Beat95yj]

You already did the hard part in finding the velocity, now estimate the distance and work backwards

 

[Mieser]

You already did the hard part in finding the velocity, now estimate the distance and work backwards

I thought it was 'easy'.......go ahead then.....I'll wait....

I honestly can't think of a good way to quantify what the 'impulse' should be without some testing. I'd like to see someone do a test with 3 ropes of different diameters with the same input vehicle/speed and record the peak force on the anchor with a load cell that has the resolution to catch a pretty narrow peak.

My gut feeling is that we will see quite a large swing in peak force from smaller to larger rope diameter. ( as long as the ropes are reasonably in their operating envelope )

I do think it is interesting that just the rough kinetic energy is approaching what the 1" rope MBS 'should' have been. That doesn't leave a bunch of margin for a short impulse where we should have seen the rope break vs the soft shackle. The rope sure didn't look like it was stretching very much (longer impulse, delta time ) in the video.

 

[white-rhino]

Here, let me help with all your calcs, stop watches, distances, speeds and velocity.

In this instance, the answer is: too fucking much.

There is a reason I tell my students a max of 5' with a mild tug. Anything more than that and you are putting "something" at risk. Why? Because anything beyond that is taking a risk that you can't predict.

 

['84 Bronco II]

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.

D-rings (AKA chain shackles) are used all the time

Fine them have it your way.

Here you go, straight from Crosby's website:

Cool, since you’re educating us which is which?

See above.

Ive been working as an ironworker for 22years and am a "certified rigger" for what thats worth.... and have never heard of a bow shackle before this thread

Sounds like your certification isn't worth the paper it's printed on

 

[gt1guy]

To straighten out the confusion on shackle nomenclature.

D-ring shackles are for chain. There hasn't been a single picture of a D-ring shackle posted in this thread yet.

This is a D-ring shackle.

What everyone is calling a Bow shackle is actually called an Anchor shackle. The names are interchangeable, but the technical name is Anchor.

Anchor shackle.

There's a fuck ton of different styles of anchor shackles.


edit: missed it by one minute

 

[Beat95yj]

To straighten out the confusion on shackle nomenclature.

D-ring shackles are for chain. There hasn't been a single picture of a D-ring shackle posted in this thread yet.

This is a D-ring shackle.

What everyone is calling a Bow shackle is actually called an Anchor shackle. The names are interchangeable, but the technical name is Anchor.

Anchor shackle.

There's a fuck ton of different styles of anchor shackles.


edit: missed it by one minute

I have never seen a D shackle like that. But I have never worked in rigging or done any professional rigging.

 

[Beat95yj]

I thought it was 'easy'.......go ahead then.....I'll wait....

Meh, That sounds like work. If I’m going to do work, I should probably do the work I get paid for. 😆.

 

[2big bronco]

I have never seen a D shackle like that. But I have never worked in rigging or done any professional rigging.

Ive seen one but never at work doing rigging stuff.

 

[Clb]

Feeling froggy here...
Just to

Looks like the derail is a happening....
Let's just keep it in the regular tech portion of the forum, it doesn't need to be in the ibb part.
What's dis?

 

[CarterKraft]

Feeling froggy here...
Just to

Looks like the derail is a happening....
Let's just keep it in the regular tech portion of the forum, it doesn't need to be in the ibb part.
What's dis?

D ring...

 

[Winchested]

D ring...

Weld on "D" ring. For trailers...

From Crosby's site... Commonly referred to by riggers as Anchor or Bow shackles.

 

[CarterKraft]

Weld on "D" ring. For trailers...

From Crosby's site... Commonly referred to by riggers as Anchor or Bow shackles.

The D ring doesn't weld though...

Weld on pivot link?

 

[aczlan]

The D ring doesn't weld though...

Weld on pivot link?

TECHNICALLY, the D-Ring assembly pictured above was intended to be bolt on, not weld on

Aaron Z

 

[gt1guy]

I have never seen a D shackle like that. But I have never worked in rigging or done any professional rigging.

If I've seen one I can't remember. They don't really use chain anymore. The fucks overseas just love them some cargo straps.
In fact, I haven't seen a screw pin shackle at work in over 10-15 years. Guess people were too stupid to install the shackle the correct way to not have the pin roll out. Everything is the bolt/nut type now. Not even worth stealing and bringing home any more.

Feeling froggy here...
Just to

Looks like the derail is a happening....
Let's just keep it in the regular tech portion of the forum, it doesn't need to be in the ibb part.
What's dis?

Ask what a master link is?

TECHNICALLY, the D-Ring assembly pictured above was intended to be bolt on, not weld on

Aaron Z

Wrong

 

[aczlan]

Wrong

Not referring to the one that CarterKraft posted, referring to the one Clb posted, this one:

Aaron Z

 

[Clb]

Could be attached with a carriage bolt [ eta like 2] but I chose migtite
Freaking autocorrect

 

[aczlan]

Could be attached with a carriage bolt but I chose migtite

Probably using 2 carriage bolts would have been better than one, but migtite is even more secure when done right

Aaron Z

 

[Winchested]

I love how far off we've derailed this haha.

 

[OHV Wildcat]

Wow, nine pages.

Here’s a pro tip from an idiot. If you’re extracting a heavier vehicle with a lighter one, never just put your kinetic rope through the Jeep’s d-ring in a half hitch. I don’t know if it’s unsafe or anything. But if you then have to yank pretty good, the kinetic rope will permanently install that tension into the half-hitch knot. There was no getting that rope off the d-ring, even after my buddy let me take it home to work on with tools. That simple knot was hard as a rock. Eventually, the rope had to be cut to at least salvage the D-ring. So, make up your kinetic rope with something else, don’t half-hitch it back to itself. I mean, in this situation I could’ve just unscrewed the d-ring and ran the rope loop through it, but that would’ve required grabbing a pair of pliers or something.

 

[arse_sidewards]

Does it do that when you half hitch them to each other.

I've half hitched plenty of straps to each other and I just pound them out with a hammer.

 

[ApeEater]

Does it do that when you half hitch them to each other.

I've half hitched plenty of straps to each other and I just pound them out with a hammer.

if the pull is hard enough, yes. The rope stretches (narrows), and then pulls back to relaxed length (expands).

 

[Clb]

Does it do that when you half hitch them to each other.

I've half hitched plenty of straps to each other and I just pound them out with a hammer.

Run a stick or dowel thru the knots intersection.
Pulls essentially the same but comes right out
..

 

[Clb]

So I just heard from one vendor that the minimum bend radius for a "stationary bend" like this situation to be @ least, and no smaller than the rope dia