Unrated Beams?

[dmacmorris]

Hey

 

Hope someone can clear this up for me, I am wanted to rig a sound truss but the SWL beam is abit to far out so I need to brail the truss back and wanted to know is this against Health and safety or is brailing on a unrated beam ok.

 

Any help would be much appreciated.

 

David

[ImagineerTom]

If you don't know what weight the bar can take, how do you know it can take the weight you want to hang on it?

[dynamo_ozz]

I think the question here should have been: "Is hanging a load on an unrated beam/point ok?" To which the answer would be: "No". It would be wise to get a structural engineer's opinion before hanging anything on any structure if the SWL is unknown. Instead of brailing, which in my opinion should be avoided unless there is no other way, have you considered using bridles? Sounds to me that you might benefit from a rigger's assistance on this issue. But first, you need to find out the SWL of the point.

[Seano]

is this against Health and safety or is brailing on a unrated beam ok.

What is "against health and safety", or more specifically LOLER (clicky) is for a lifting operation not to be "planned, supervised and carried out in a safe manner by people who are competent".

 

Regarding your 'unrated' beam - you can load that beam if it's sufficiently strong and stable to support the load you're putting on it.

You're essentially asking whether it is or not, and that of course is impossible to answer based on the (lack of) information in your post.

(Though even if you provided much more information, you'd be *very* unlikely to get an answer here.)

It seems you need a rigger and/or a structural engineer.

[dynamo_ozz]

is this against Health and safety or is brailing on a unrated beam ok.

What is "against health and safety", or more specifically LOLER (clicky) is for a lifting operation not to be "planned, supervised and carried out in a safe manner by people who are competent".

 

Regarding your 'unrated' beam - you can load that beam if it's sufficiently strong and stable to support the load you're putting on it.

You're essentially asking whether it is or not, and that of course is impossible to answer based on the (lack of) information in your post.

(Though even if you provided much more information, you'd be *very* unlikely to get an answer here.)

It seems you need a rigger and/or a structural engineer.

 

I fully agree with Seano. You shouln't attempt to do this on your own.

[ace]

Hi all,

 

Did I read this question differently to everyone else? I believe the the OP wanted to hang the truss on the rated beam, but brail it back towards the unrated beam (ie with the brail lines attatched to the unrated beam), which sounds like a much more sensible question! I am afraid I don't know the answer, but perhaps the OP can confirm if this is what he was asking!

 

Chris

[Andrew C]

Did I read this question differently to everyone else?

Possibly not; but if the speaker hang is heavy, you could introduce significant loads onto a beam not designed for ANY lateral load. You need experience, or a "proper man" to make this call.

[dynamo_ozz]

And should that brail fail, imagine the swing and likely catasthrophy when the trus will swing and hit everything in its way.

[Seano]

Did I read this question differently to everyone else? I believe the the OP wanted to hang the truss on the rated beam, but brail it back towards the unrated beam (ie with the brail lines attatched to the unrated beam), which sounds like a much more sensible question!

No you did read it right I think, it falls into the general area of: "If you have to ask..." ;)

[dmacmorris]

Hi all,

 

Did I read this question differently to everyone else? I believe the the OP wanted to hang the truss on the rated beam, but brail it back towards the unrated beam (ie with the brail lines attatched to the unrated beam), which sounds like a much more sensible question! I am afraid I don't know the answer, but perhaps the OP can confirm if this is what he was asking!

 

Chris

 

Yeh sorry this is exactly what I meant.

[TomM]

In which case, if you don't have sufficient experience to know the answer and have to ask here, the answer is YOU shouldn't be doing it. However, a suitably competent person may be able to make an assessment on-site and decide if/how the truss can safely be brailed.

 

T

[stevei]

Cant think the last time I brailed anything to make sure it is in the right place.

 

A Bridle is by far the better way to do this (though impossible to advise without seeing). To be sure its ok then a site visit by a rigger is the only way forward, if you need to ask the question then...........

[TomM]

Cant think the last time I brailed anything to make sure it is in the right place.

 

A Bridle is by far the better way to do this (though impossible to advise without seeing). To be sure its ok then a site visit by a rigger is the only way forward, if you need to ask the question then...........

 

I think brailing is only common in theatres with installed flying capacity. In those environments it is usually easy to brail a bar than bridle between two.

 

I would agree though, that for a positional brail, a bridle is usually better when directly rigging off beams. I guess the other possibility relevant to the OP is a line for angling the speaker hang, in which case a bridle isn't the answer, but he needs to consult someone with the relevant experience and let them see the rig to work out the best way of doing this.

[Stan Hope-Streeter]

Hey

Hope someone can clear this up for me, I am wanted to rig a sound truss but the SWL beam is abit to far out so I need to brail the truss back and wanted to know is this against Health and safety or is brailing on a unrated beam ok.

Any help would be much appreciated.

David

 

Asking such a question on an internet message forum is strong evidence that you are out of your depth and need to hire a professional.

 

It's no different from asking a random collection of people in a pub, or in this case the local Students Union bar. The Blue Room is largely frequented by schoolkids, students, and dreamers - many of whom are too young to be in a pub anyway. How do you know if the person who responds to your enquiry is one of the few actual pro's here?

 

The only true answer to your question is "WE DON'T KNOW, SEEK PROFESSIONAL ADVICE"

[DSA]

If you know you would be exceeding the stated SWL, then you need to take proper professional advice. Is there any way of reducing the weight of the hang? That would be your cheapest option... How far over the SWL is the applied load, and what is the loading configuration you wish to use? How recently was that SWL determined?