Rigging 101 for Other Departments?

Calc

Well-Known Member
Can anyone point me to some info I can use to educate our Campus Facilities department regarding the who/whats of rigging?

Background: We rent out our arena for large events. Occasionally, the renters want to contract in lighting/audio/video and rig them from the roof. Up until recently this would only be once every couple of years, but we now have a couple of annual recurring clients that want to do it. The last engineering survey of the building was done quite a while ago, and there have been numerous changes since then (re-roof the building, move the scoreboards, replaced lighting, etc.). From the facilities department's view, each of these individual changes have been relatively small, so nobody ever asked for an updated capacity spec. Taken as a whole however, I'm sure they have affected the load capacity.

I asked Facilities for an updated document I could pass along to the rigging companies. The engineering firm that the University has on contract won't send me an updated spec, even though they were the authors of the original one. They insist that we provide a list of equipment to be hung, and they'll sign off that it's safe. This means that generally the info has to travel AV Contractor > Client > Me > Facilities Dept. > Engineer, and back. At the last event the engineer showed up, and began questioning the safety of using standard steel stingers, gakflex, and shackles for attachment to the steel. He also demanded a full diagram of each individual point with each component labeled. We complied, but that's impractical to do in advance due to the day-of changing needs/gear in our industry.

It's clear to me that both Facilities and the Engineer are not familiar with the rigging process at all. They're hesitant to sign off that things are safely hung (understandably with their unfamiliarity), but in reality that's the rigging company's job. I'm looking to them for what limits we need to work within. They're trying to go above and beyond that, but in the process wandering beyond their specialty and the result is that it's gumming things up.

So I'm looking for general info that I could send them that would explain rigging in language they can understand.
Something that might cover standard rigging methods, and who's responsible for what. I've tried explaining it to them, but it's not making it across and I think an outside independent source would help.

Alternatively, does anyone else have any other recommendations on a different way to proceed?
 
I have seen places require individual sign off on each point, but that was usually in outdoor situations where you are dealing with a truss based mobile stage. In that case, I think it is time you reach out to a new engineering firm. You should be able to get the loading criteria for every beam in your venue along with an overall roof load. Teaching engineers how we work can be done, but it will take years to do. We did it 10-15 years ago and have had a good relationship since. It took years to do. You don't have that much time.

If there is a small pot of money behind this I would give these people a call:
http://www.mgmclaren.com/leadership
http://www.geigerengineers.com/karen-lynch

The company we use locally is: https://www.springlinedesign.com/
 
My experience is structural engineers will rarely say this is how much an existing structure will hold, but will determine if it is strong enough to support a specific given load. I think that is exactly what you ran into. I don't know the arrangements for your facility but if there is a system of beams or framing where tours usually load to, consider diagramming this and assigning a reasonable maximum load - probably a multiple of half or one ton hoists - and having the engineer says yes or no to that. Its the lowest common denominator - you can hang this much at the center of each beam and every beam is loaded simultaneously.

There are a few structural engineers who are much more familiar with this work who - for a fee - could probably work with the university's designated structural engineer. I can provide some names if you need.
 
My experience is structural engineers will rarely say this is how much an existing structure will hold, but will determine if it is strong enough to support a specific given load. I think that is exactly what you ran into. I don't know the arrangements for your facility but if there is a system of beams or framing where tours usually load to, consider diagramming this and assigning a reasonable maximum load - probably a multiple of half or one ton hoists - and having the engineer says yes or no to that. Its the lowest common denominator - you can hang this much at the center of each beam and every beam is loaded simultaneously.

There are a few structural engineers who are much more familiar with this work who - for a fee - could probably work with the university's designated structural engineer. I can provide some names if you need.

Then you start throwing bridles in and everything goes out the window!
 
Then you start throwing bridles in and everything goes out the window!
Lol, exactly. There's no standard setup, as it changes based on planned attendance. Some length-wise, Some width-wise, and one split the arena into four separate quadrants.
I'll try and get discussion on the topic rolling again here, but I may take some of you up on the offers for other contacts for the engineer to consult with. Thanks!
 
I would send them some copies of other venue tech packets with the rigging info.

As a touring rigger I want to know a few things in the advance or when I walk in the door.
1. Total roof load - most buildings put these into 3 sections, end stage, around the scoreboard and the far side.
2. Max load per beam -
3. Oddities, can we wrap the catwalk, are some beams only riggable from boom lifts, is it possible to go to high steel, goofy baskets or steel requirements and any house policies that aren't industry standard.

When I am the tour rigger most of my shows are small enough that we can get by off the boiler plate tech specs. I've been on shows as other positions where we are close to the building max capacity so the shows rig plot gets reviewed by an engineer. Not sure what side of settlement that comes out of though.

I was the motor tech on a show with 80 2 tons on a flight track. Every time the promoter rep sent out the advance packet an email would come back almost instantly saying the roof capacity is only 200,000 pounds and there would be no way to hang the show. It took us a few times to find the best way to discuss our needs with the buildings and their engineers. When ended up taking a video of the load cell system during the flight sequences to show that not every motor was loaded to capacity at all times. The 6 near the heavy trolley would be heavy but others would only have a couple hundred pounds on them. Even with that the head rigger would be drawing every bridle in CAD and doing a weight report where all the weight of the show would end up on the roof structure.

All that to say there is certainly room for improvement in your rigging advance, but it might not be the last time you have to call the engineers
 
I would send them some copies of other venue tech packets with the rigging info.

As a touring rigger I want to know a few things in the advance or when I walk in the door.
1. Total roof load - most buildings put these into 3 sections, end stage, around the scoreboard and the far side.
2. Max load per beam -
3. Oddities, can we wrap the catwalk, are some beams only riggable from boom lifts, is it possible to go to high steel, goofy baskets or steel requirements and any house policies that aren't industry standard.

Agree totally. And with that max load you need both the vertical "dead" load and the amount of horizontal load that beam can take.

Engineers who have no idea what we do really do not like to deal with us. It scare the absolute hell out of them... and for good reason. Find one that knows how the business works and go from there. Alternativly, find a local arena that is not you and have them go to a rigging call... preferably with a good head rigger who can actually walk them through what it is they were doing all morning.
 
I would recommend you contact a engineering firm like Clark/Reder http://www.clarkreder.com/ who specialize in entertainment engineering.

I will also say I have a very close relationship with them so I am biased in recommending them.
 
Clark Reder would be at or very near top of my list. Sean Nolan and Steve Walker also.

Besides the diagram soundman mentions, label the beams they can use with the load max.
 
Part of the discussion with both the university and the engineers might include ETCP information. Having a certified rigger in charge might calm many nerves. Engineers love to rely on expertise, even if it's not their own.
 
We can recommend both Clark Reder (mentioned above) and Entertainment Structures Group (ESG AKA Schaefer) http://schaefer-inc.com/

We regularly contract with both, and they do excellent work.
 

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