Do you twist your safety chains to shorten them?

[2kwik4u]

I'll admit, I've been doing this for years. I've just recently been spurred to think about the actual effects of this, and why it's a bad idea.

Backstory, I'm working on some analysis work for a piece of vibratory equipment that is suspended by steel cables. This machine operates around 500rpm or so (9 hertz), and weighs around 80k lbs with product included. It hangs from (4) wire ropes that are secured with pin connections at each end. Customer replaced the pins with bolts, and then cables failed. So I get to analyze the failure, write a knowledge base article, and ultimately do root cause analysis on the failure. We use cables to suspend a good deal of equipment and it's rarely an issue, so I was sitting here thinking about the failure mode, and how the cable was being loaded outside of it's intended direction.

That got me to thinking about how I twist the chains on my trailer to keep them shorter and off the ground. The chains are FAR to long for the hitch setup I have, and I've just twisted them up a bit to make them shorter. It's worked fine for keeping them off the ground and not "clinking about", however I had never put much thought into the loading on the chains should then be called to action. So I went off researching and found this great article.

The Low-Down On Twisting Safety Chains - From The Mechanic's Post

Should you twist a trailer safety chain to make is shorter? Here is the Engineering on why twisting safety chains is a bad idea.

mechanicalelements.com

They talk about twisting chains, how and why it's a bad idea, and how the loading differs between a straight chain and a twisted chain. That article also links to the below video that is a pretty good example of the decreased strength of the chain.

Here's what my current hitch setup looks like. You can see there is significant amounts of twist in the chain to keep it shortened and off the ground. I'll be redoing this setup the next time I have everything hooked together. No reason not to, as it's a simple remove a bolt and shorten up the chain available for latching.



I'm curious. Anyone else twist chains like this to shorten them?

 

[Babin Farms]

If your chains are too long you could always put a bungee on them and pull back to the trailer somewhere to keep them from dragging or just cut to the desired link/length. The only issue I see with shortening them is if you get a different vehicle and they are to short, you'll be replacing chains. Is twisting them going to diminish their strength to the point that they break if the ball fails, I doubt it but anything is possible. I see this as an issue with larger trailer loads or/and too light of chains. Glad I have cables instead of chains on my MFI trailer that already have a curvature in them to keep from dragging.

 

[BlkGS]

I usually would have mine run to the opposite side to get the length right.. Thinking about it now, that's seems like also not a very great idea, should you actually need them to work.

 

[2kwik4u]

I usually would have mine run to the opposite side to get the length right.. Thinking about it now, that's seems like also not a very great idea, should you actually need them to work.

They should definitely be crossed under the ball to create a "cradle" of sorts. should the trailer come off the ball.

The only issue I see with shortening them is if you get a different vehicle and they are to short, you'll be replacing chains. Is twisting them going to diminish their strength to the point that they break if the ball fails, I doubt it but anything is possible.

I think I'll just pull them up a bit to they aren't twisted and rebolt. Won't actually shorten the chain any, just move the attachment point up a few links to eliminate the twist.

No idea if the forces are enough in an emergency to break the chain or not. Would hate to be on the wrong side if I ever find out though.

 

[Crob83]

I sure do, always have with my skis and now the boat

 

[Sean R]

I've never twisted them but I always cross them.

 

[Mike Clark]

I replaced my chains with cables designed for the application , pre-coiled, so long enough to reach where you need to get to but always coiled to keep off the gound and no noise at all.

 

[AZMark]

I always twist and cross them. Dragging chains is a very big deal out west for brush fires.

I never thought about it weakening the chain. Uhaul always does it so I assumed it was safe.

 

[AZMark]

I'll admit, I've been doing this for years. I've just recently been spurred to think about the actual effects of this, and why it's a bad idea.

Backstory, I'm working on some analysis work for a piece of vibratory equipment that is suspended by steel cables. This machine operates around 500rpm or so (9 hertz), and weighs around 80k lbs with product included. It hangs from (4) wire ropes that are secured with pin connections at each end. Customer replaced the pins with bolts, and then cables failed. So I get to analyze the failure, write a knowledge base article, and ultimately do root cause analysis on the failure. We use cables to suspend a good deal of equipment and it's rarely an issue, so I was sitting here thinking about the failure mode, and how the cable was being loaded outside of it's intended direction.

That got me to thinking about how I twist the chains on my trailer to keep them shorter and off the ground. The chains are FAR to long for the hitch setup I have, and I've just twisted them up a bit to make them shorter. It's worked fine for keeping them off the ground and not "clinking about", however I had never put much thought into the loading on the chains should then be called to action. So I went off researching and found this great article.

The Low-Down On Twisting Safety Chains - From The Mechanic's Post

Should you twist a trailer safety chain to make is shorter? Here is the Engineering on why twisting safety chains is a bad idea.

mechanicalelements.com

They talk about twisting chains, how and why it's a bad idea, and how the loading differs between a straight chain and a twisted chain. That article also links to the below video that is a pretty good example of the decreased strength of the chain.

Here's what my current hitch setup looks like. You can see there is significant amounts of twist in the chain to keep it shortened and off the ground. I'll be redoing this setup the next time I have everything hooked together. No reason not to, as it's a simple remove a bolt and shorten up the chain available for latching.

View attachment 150381

I'm curious. Anyone else twist chains like this to shorten them?

What is that thing bolted under your ball mount?

 

[Julian]

I've always twisted my chains. Interesting discussion. The twist chain in the test breaks at 2000lbs.....I doubt the pull on them is anything close to that if the hitch comes off the ball. For the truck dangling off the bridge scenario....thats a one in a million.

Shortening them by moving the bolt....good idea and would make it easier to hook up - eliminate that PITA twisting! But then when I looked at the photo, I realized that the chain is being held on with a washer....I wonder what the strength of that washer is!!!! Looks like a much more likely failure point than the chain!

 

[anmut]

What is that thing bolted under your ball mount?

Keeps his hitch from rattling in the receiver.

 

[2kwik4u]

Keeps his hitch from rattling in the receiver.

Yeap. Kinda works.

Unibody SUV transmits ALL the vibrations/slop straight into the cabin in the form of noise.

@AZMark

 

[2kwik4u]

I've always twisted my chains. Interesting discussion. The twist chain in the test breaks at 2000lbs.....I doubt the pull on them is anything close to that if the hitch comes off the ball. For the truck dangling off the bridge scenario....thats a one in a million.

Shortening them by moving the bolt....good idea and would make it easier to hook up - eliminate that PITA twisting! But then when I looked at the photo, I realized that the chain is being held on with a washer....I wonder what the strength of that washer is!!!! Looks like a much more likely failure point than the chain!

Yea, I noticed that as well. Probably going to modify that as well. Most likely drill a new hole and put a stainless structural washer on there.

I like the idea of moving to cables as well. Even better setup I think.

 

[RiverRat]

I do not twist chains. I think on boat trailers you’d probably be fine though. At work I consistently tow trailers loaded with equipment like Skid Steers and excavators. Much heavier trailers. I secure the machines with chains and binders. Every bend in the chain reduces its overall weight capacity, so I try to keep chains as straight as possible.

 

[Ronnie]

My two cents after having my boat laden trailer detach from my tow vehicle while doing 60 mph on a freeway, the short answer is I do not twist my safety chains to make them shorter. The long answer with rationale is:

1.Do NOT use coiled cables instead of chains but if you do make sure the cables are not so long that they will touch the ground if the trailer tongue ends up resting on them should it and/or the draw bar (which the tow ball is mounted to) end up in the cradle created by crossing the cables under the tongue and draw bar. Some people, I think most, do not realize that crossing the safety chains or cables is required by law, not because they will keep the rig together better if they are crossed but to create a cradle to keep the tongue/drawbar from dragging on the ground should they detach from the tow vehicle. I leaned about this is boating class decades ago so crossed the cables as a habit never thinking I would use the cradle.

if the cables are too long when stretched out such that they touch the ground there is a good chance that the weight on top of them will cause the cable or cables to be ground away and break. This is what happened to one of my two cables, so I ended up pulling to the shoulder of the freeway on one safety cable.

2. Dont twist your safety chains to shorten them, just reduce their length by mounting them on links further from the end of the chain. The extra chain can be secured to the trailer tongue or to the rest of the chain with a nut and bolt or zip ties. Also don’t cut your safety chains unless your sure you won’t be using any other tow vehicles to pull your boat around with. I cut one of mine on my pwc trailer and ended up having to re-extend it when I got a new tow vehicle (it is just more hassle and created a new weak point than if I just tied the extra chain up somewhere).

3. Make sure the break away / e-brake cable is in good condition and properly Attached when on the road. If it’s not working or attached properly it won’t activate the brakes like it is supposed to if the trailer breaks away from the tow vehicle. If you understand how surge brakes work you know that they don’t work if the trailer is not attached to the tow vehicle.

here is a link to my trailering incident for those interested. Also attached are a few pics from that incident as well as what my current trailers look like.

Yamaha Jet Boaters • View topic - Trailering disaster narrowly averted!

lastley, I purchased anti-rattle collars for both of my drawbars from e-trailer for around $10 each, they work well at reducing, almost completely eliminating the sounds created by the play between the draw bar and hitch when starting and stopping.
Of coarse if this noise doesn’t bother you these collars are not needed.

 

[Sbrown]

My understanding is the idea is not to so much twist each individual chain, but rather cross them multiple times; this will also shorten them without weakening them, and not cause any other problems should the trailer become disconnected. I think its important to know this because while you can modify the chains on your own trailer to fit your tow vehicle, if you're ever towing somebody else's trailer and the chains are too long, you need to have a good solution in the ol' toolbox we call a brain.