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Author Topic: What would you do? (Bad rigging issue at local restaurant)  (Read 2230 times)

Mark Cadwallader

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #10 on: December 30, 2018, 01:05:52 am »

Geez guys, maybe I'm just an old codger from a different generation with a different perspective on what's risk / what's safe...
I don't get all the safety over-lording...
Who knows how it's really hung, and honestly it doesn't take much to hang 87 lbs completely static... I'd dine under it..

The fact that the suspension point is an open J hook is enough to tell me not to go near where it is hanging. 

The size of rod that forms the hook is enough information too.

Not to mention that the chain doesn't run through the eye bolts on the top of the speaker, but it also appears to be side-loading the eyebolts.

And that's just what I see from the picture on an iPhone screen.
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Stephen Swaffer

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #11 on: December 30, 2018, 03:47:36 pm »

Here is a quote from a JBL document regarding hanging speakers.
“Lag-Screw Eyes cut threads into wood and rely upon the strength of the wooden threads to carry the load. The ultimate strength of the bond depends upon the strength of the material and total surface area threaded into it. Wood or wood fiber makes untrustworthy threads and should never be used to support overhead loads.”

I understand where you are coming from-but there are times when wood is the only framing material available  ;) .  To a degree this comes across to me as boiler plate "We're not responsible"-though in my mind the only thing the speaker builder should be held responsible for is if the fly points hold or fail.  The problem is that the language makes it difficult for me to always follow their instructions thus requiring some interpretation as to where to draw the line. (part of my day job responsibilities is overseeing hoists and rigging in an industrial facility-I do not consider myself an expert-but I do understand the issues involved safety factors and all that) One of my biggest concerns on this hang is that if one screw hook fails it comes down.

Perhaps the most effective/ethical and likely to be listened to course of action would be a note to the owner indicating your concern and the discomfort caused-and the possibility that it will influence your decision to frequent the establishment.  You are but one customer-but any business owner worth their salt knows a happy customer is worth their weight in gold when it comes to advertising.  Compliment whatever you can-and express it as a safety concern.  It is quite likely a case of someone doing what they know-and simply not knowing any better.

Our pastor became concerned about lighted exit signs because a visitor to our Christmas play expressed a concern.  Probably faster results (and certainly less friction involved) than if a demanding building official came in the door insisting we do something "or else".

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Frank Koenig

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #12 on: December 30, 2018, 05:15:06 pm »

There exists engineering guidance for lag screw connections into timber for both tension and shear. I found it a few years ago when I was designing a steel deck to go on an existing wood house. The majority of the connections in this case were bolted through wood framing members using nuts and large washers but there were several locations where a blind fastener was required. Incidentally, all the plans were gone over and stamped by a licensed civil engineer before being approved by the county.

Regulations aside, what I think about when flying a speaker, or anything else for that matter, is redundancy, or the lack thereof. The least reliable connections should be redundant so that if any one fails the remaining ones take the load and give visual warning to the inhabitants. The sometimes unavoidable single points of failure, those where failure would cause the object to fall, need to be of the highest reliability and conservatively rated: forged, rated, eyebolts; grade-8 cap screws; etc.

The OP's example fails miserably where the iffy hook goes into God-knows-what in the ceiling. Were the speaker suspended from, say, a couple of pieces of Unistrut lag screwed at multiple points into wood framing using suitably large and long screws, I bet a CE would sign off on it. Better to add a wire rope loop with a WLL  >10x the weight of the speaker that goes over a large framing member or two. That would satisfy redundancy and I, at least, would be happy.

As for what to do, at best I'd notify the city (San Jose, I'm guessing) building department and hope something happens. Beyond that, don't let your friends sit under it.

Happy New Year.

--Frank

PS:There was a great quote at the end of the recent movie "Apollo 8".  As the astronauts are being hoisted into a helicopter after splashdown one of them says (approximately), "I spent the last ? days in a spacecraft where everything was designed with redundancy. Now I'm hanging from a single 3/8 in. wire rope." Man after my own heart... -F

« Last Edit: December 30, 2018, 05:28:48 pm by Frank Koenig »
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Douglas R. Allen

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #13 on: December 30, 2018, 07:22:01 pm »

   Do those speakers require a pull back?  Those rig points look close to the front. If it does have pull backs I wonder how it will turn/spin if/when? it falls..  Shudder.....

Douglas R. Allen
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Randy Pence

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #14 on: January 05, 2019, 10:32:38 am »

Geez guys, maybe I'm just an old codger from a different generation with a different perspective on what's risk / what's safe...
I don't get all the safety over-lording...
Who knows how it's really hung, and honestly it doesn't take much to hang 87 lbs completely static... I'd dine under it..

yea, who needs seatbelts in cars?
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Riley Casey

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #15 on: January 05, 2019, 01:08:17 pm »

As a government certified old codger I'm good with extremely high rigging standards. You and I may not have much runway left but I have a keen interest in making sure my kids and grandkids come away healthy and whole from the next show they attend.  I have pointedly explained to the owners of small bars that my kids have played at that the speakers they've hung in similar ways were not safe and if they were that way the next time I was in attendance I would make a call to the ABC board.  Guess what, it worked.  Bar and restaurant owners couldn't care less about whiney old patrons but they are scared shitless about their liquor license.

Geez guys, maybe I'm just an old codger from a different generation with a different perspective on what's risk / what's safe...

Mark Oakley

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #16 on: January 05, 2019, 01:31:46 pm »

they are scared shitless about their liquor license.

Absolutely true. I've invoked the term "Liquor Control Board" in conversations waaay back when I was playing in bars that were slow to pay after my band had played. Worked like a charm.

-Mark
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Tim Tyler

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #17 on: January 05, 2019, 04:53:33 pm »

Geez guys, maybe I'm just an old codger from a different generation with a different perspective on what's risk / what's safe...
I don't get all the safety over-lording...
Who knows how it's really hung, and honestly it doesn't take much to hang 87 lbs completely static... I'd dine under it..

Mark - another old codger here - in all the decades I've been on this forum or following pro sound issues, I've seen catastrophic sound system damage due to high wind, fire, flood, tsunami, vehicle crashes, landslides, tornado, hurricane, improper tent construction and warfare - those are the only ones I remember specifically.  I've never seen or heard of speakers such as the one on this thread actually falling.  It's sloppy and probably illegal, but I think the actual danger is grievously overrated.  I think the OP should make some calls and then get over it.

Cheers,
-Tim T
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Dave Garoutte

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #18 on: January 05, 2019, 05:52:54 pm »

I doubt if a speaker falling on the ground in a bar would make national news like the other things you described.  It may well happen more often than we are aware of.
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Lee Douglas

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Re: What would you do? (Bad rigging issue at local restaurant)
« Reply #19 on: January 05, 2019, 09:39:11 pm »

Speakers fall.  Links from page one of simple search bear this out.  To bury your head in the sand and pretend otherwise until it happens within your limited little world is just ignorant.  If your conscience is clear, looking other way when you see a potential problem, so be it.  But don't belittle others for showing concern and trying to make others aware, who may not otherwise know of the potential for failure.  I think there should be a sticky of compiled safety failure issues links that could be shared, if needed.  Sometimes a picture of three year old with his head sliced open and traumatic brain injury might be enough to warrant a second look.

https://kdvr.com/2014/09/06/speaker-falls-on-teen-at-movie-theater/

https://www.dailymail.co.uk/news/article-4481614/Boy-three-badly-injured-speaker-fell-head.html

https://vancouverisland.ctvnews.ca/woman-knocked-unconscious-by-falling-speaker-at-rcmp-musical-ride-1.3565769
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