Turnbuckle failure after 7 months.

[bannertime]

Had two over the street banners, 30in x 50ft, across 100ft of road. City had telephone type poles installed just for the project. Spec'd the cable and all the equipment based off of wind load calculations. Ordered everything through one supplier based off their recommendations for the job. The turnbuckles they sent were a little thinner than 3/8 in bolts with a bolted closure instead of an eye bolt. We didn't like how thin and cheap they felt so we went with 3/8 in with the eye bolts. We use 3/8in eye bolts to install 20ft inflatables on top of buildings. So we had faith in them.

7 months later, yesterday, we got a call saying one of the cables was hanging down. There were failures on three of the turnbuckles. The eye bolt has opened up. Today we replaced them, opting for 1/2in turnbuckles with eye bolts. That's what we could get from the local hardware store. We'll be replacing both banners and tightening the cables in a few months, so for future reference, we'd like know which is better. The eye bolt or the one with the bolted enclosure. See attached. Thanks.

 

[2B]

well if the ones that failed were the eye bolt then the bolted enclosure is the better option

 

[bannertime]

That's just speculation, those could have failed much sooner.

 

[signage]

With the eye not being welded closed that is the weak point. So the one with the bolt in would be stronger as long as the correct grade bolt is used.

But this sounds like an installation error.

 

[rjssigns]

Clevis style is the best. It is how you hook cable or chain to any type of load. The only eye-bolts I ever used for lifting were forged and made expressly for that purpose.

Note: The problem with eye-bolts, even forged pieces, is they are sensitive to the angle the chain or cable is pulling.

I used to move industrial equipment and had to go through training to learn the do's and don'ts. Even though you are rigging banners the same load safety rules apply.

 

[Billct2]

I agree about the eye bolt style being the problem. But I would think having wind load specs and using a piece of hardware that is supposed to handle that spec should work, no matter the style. Of course I always like to step it up on any hardware.

 

[bannertime]

Clevis style is the best. It is how you hook cable or chain to any type of load. The only eye-bolts I ever used for lifting were forged and made expressly for that purpose.

Note: The problem with eye-bolts, even forged pieces, is they are sensitive to the angle the chain or cable is pulling.

I used to move industrial equipment and had to go through training to learn the do's and don'ts. Even though you are rigging banners the same load safety rules apply.

Now that I read that, I realize that is all we used when I was working in the oil industry. And the eyebolts that were on the machines were welded and forged closed.

We use eye bolts nearly every day of the year to secure large advertising inflatables onto roof tops. In my memory, about 15 years ago, was the only failure we had with an eye bolt. A plastic bag flew onto the intake of the blower and stopped air flow. The balloon then partially deflated and ended up ripping a commercial a/c unit about 4 feet away from it's base, then the bolt pulled out of the wall. So it wasn't even the eye that failed.

But I would think having wind load specs and using a piece of hardware that is supposed to handle that spec should work, no matter the style. Of course I always like to step it up on any hardware.

This might have been where we messed up. From my understanding, we provided the specs to the supplier and asked for parts that could meet those. We didn't like the turnbuckles we got, so we stepped them up in size. They are still on the truck, so I'll get pictures of them when it gets back. Probably got something inferior. Everything else on the install is fantastic. This was my first over the street install. Not for the business, but our veteran installer retired last year.