Screen Rigging

[Jivemaster]

It's not the DOing thats difficult, it's the designing, and planning. A suitable engineer could site survey and design something that your crew could assemble. Someone has to accept the role of Design Authority, to predict by calculati0on that the design, implimented by enthusiastic amateurs, WILL BE SAFE, from assembly, use and disembly to final clearance.

 

 

They have to be prepared to account to HSE, and coroner's and crown courts.

 

An amateur approach should take as many known good parts as a starting point as possible.

 

A white sided lorry seems a good start. Then hire some contractors bags of sand/ballast to keep it solidly on terra firma. You have somewhere to put the dialogue speakers behind the screen and the bins under the body. AND it only takes a licensed driver to clear it all up.

 

You describe a "society" if this is an unincorporated body you can all each and singularly become liable if the society cannot pay.

 

You should still run the design by your insurers as they will remember the incidents cited and linked above.

[Pete]

A white sided lorry seems a good start. Then hire some contractors bags of sand/ballast to keep it solidly on terra firma.

 

 

Sorry Jivemaster it could be me being really thick,but why would you need to weight the lorry?

 

Pete

[Seano]

.. but why would you need to weight the lorry?

In case it blows away, like this thread caught in the crossfire of a 'more safety conscious than thou' arms race.

[Dave]

On my travels, I have seen several trailers (large artic style used for advertising) parked in fields by motorways blown over onto their sides. I guess they were empty...

 

Just on the original topic, one point to stress (as mentioned by others in not so many words) is that if you haven't got the budget to do a project safely, then you can't do it, period.

[Ike]

As far as I see it you have two main options;

 

1, Build a goalpost arrangement out of truss, attach the screen, raise it up then fit guys and outriggers to prevent it toppling over.

 

2, Build a counterweighted scaffold and attach the screen directly to it. This is probably the easiest to do cheaply and safely as there are hundreds of scaffold companies who have experience of building covered and freestanding scaffolds therefore no need for particularly specialised equipment or skills beyond those of a scaffold designer.

 

Whatever method you should make sure the screen will tear from its fixings or panels will rip before the structure goes over. If the wind picks up and the the screen doesn't detach/tear evacuate and run away, don't under any circumstances let anyone go to try and release it. The same goes for anything from a £2 bed sheet to a £200,000 LED screen, the decisions get harder but the choice should always be the same.

 

All the other comments are still valid and I would still go for a professional scaffold company, once you add up the costs it probably isn't that much cheaper to do it yourself as it will take five times as long, five times as many people and god only knows how much more in insurance.

[browna]

Have you thought about hiring out a crane, for an hour or so, depending on price?

 

Just an idea!

[Simon Lewis]

Have you thought about hiring out a crane, for an hour or so, depending on price?

Just an idea!

 

The extended discussion above centred around what forces would act upon such a large screen. Those same forces acting on a screen suspended from a crane jib would mean that the crane itself could be in danger.

 

OK, so the driver could drop the load fairly quickly, but that might put people at risk, and a sudden gust might mean that such action couldn't be carried out quickly enough.

 

Furthermore, from what I have seen of crane work, they won't take up a load when the wind speed exceeds a given limit.

 

 

Perhaps the crane might not be too suitable? ;-)

 

 

Simon

[Pete McCrea]

You possibly open your self up to issues with the terminology of 'Lifting' and 'Suspension'. I believe for something to be able to suspend a load there should be additional safety features in place to prevent sudden dropping of the load should the hydraulics/winch fail etc.

 

I have questions that are unanswered on this with respect to using Telehandlers for suspending speaker clusters, and would rate cranes in with this.

[kitlane]

Read these books

 

http://images-eu.amazon.com/images/P/0717624536.01.MZZZZZZZ.jpg

 

http://images-eu.amazon.com/images/P/1904031064.01.MZZZZZZZ.jpg

Now consult an engineer

[afrophish]

hi

 

I would personaly go and try and find a pro team to do this for you I would personaly recomend tega ive worked with them in the past and there very good and effective

[BlueShift]

DISCLAIMER - Im not an outdoor screen rigger, merely musing on the topic....

 

Seems to me that attaching the screen to an artic trailer as someone previously mentioned is far from a stupid idea. You then have a significantly stage base structure (designed to handle a level of wind loading) and its easier to position. I wonder if people ever do it this way...

[Dj Dunc]

Now just a new person speaking here, but theoretically, wind travels at ground level along surfaces?. so therefore, if you used an artic trailer with screen down the side ( with the rear of the screen into the wind) then this would hvae a fairly high chance of getting taken out by wind at a certain velocity. therefore, you deflate the tires completely and lower the centre of gravity as much as possible. then you add a slope of some kind on the windward side of the artic (to the top of the screen), using a strong scaffolding prism covered in a taught tarp. this way any wind will be lifted up over the trailer and out of harms way. If the wind does decide to change direction and push onto the screen, then the scaffolding should add strength to the trailer, along with the added weight so should hold it upright. I know this has many implacations but as Blueshift said, im only musing

[Pete McCrea]

.... a fairly high chance of getting taken out by wind at a certain velocity.

 

I would think the that the wind speed that would blow over an artic trailer would probably also have led to cancellation of the event.....

[Dj Dunc]

didnt think about that. duh

[Simon Lewis]

Have a look back at the original poster's question, and the reasons why such solutions as a trailer were not really suitable...

 

It's not so much that you couldn't take this approach, but that there wasn't the expertise, the engineering design to ascertain whether the structure was safe, the assessment of risk, the knowledge of the structural principles involved etc., etc.

 

These were trotted out, and unfortunately the OP didn't consider the advice to be too palatable...