Safety Issues in the Theatre

I'm not against the use of safety cables, but has any one actually ever seen a safety cable catch a falling instrument or be used for more than a visual safety measure? I've been doing lights for 15years now, and have never seen an instrument fall and be caught by a safety cable. I've got more use out of safety cables by using them to hang them off a ladder when hanging likes (this way i don't have to make as many trips)

Safety cables are actually quite important. Just because you haven't seen a light fall doesn't mean it isn't going to happen. C-clamps are inherently flawed devices, if you look at the way forces are applied to them and the materials they are made of it is almost like they are designed to fail. You don't have to over-tighten a C-clamp to much to weaken it, and a little bit every time you hang the camp adds up. Sure, in general we see clamps fail while they are being hung or struck, but the one that slips by could be the one that falls.

This of course is not to mention that there are a lot of other things that could cause a c-clamp to fail. A shock-load to a lighting position, say a running fly that hits the grid, could cause the c-clamps on multiple instruments to fail.

As for the comment that was made in a post about the the yoke bolts failing before the c-clamp, that also seems doubtful. On a source 4 the yoke bolts are at least grade 5 bolts, I don't know offhand what the rated strength of the bolts is, but I would have more faith in them than the C-clamp.

I have seen instruments fall, and it isn't pretty and luckily no one was hurt. As I said, just because you haven't seen it doesn't mean it won't happen. Being lax about safety is not a good practice at all.
 
We had a 6.8 magnitude earthquake hit here in 2001. I had 150 kids in my high school little theater watching a guest speaker. I was in the booth at the time. I watched and listened as about 25- 360Q's with 20+ year old C-clamps, hanging over the audience, banged together for about a minute. Luckily no c-clamps failed but I was sure glad I had safety cables.
 
I have seen a C clamp fail and there was a safty on the fixture. I have also had a S4 droped 3' away from me from about 20' above my head i perfer the option with a safty.

JH
 
We had a 6.8 magnitude earthquake hit here in 2001. I had 150 kids in my high school little theater watching a guest speaker. I was in the booth at the time. I watched and listened as about 25- 360Q's with 20+ year old C-clamps, hanging over the audience, banged together for about a minute. Luckily no c-clamps failed but I was sure glad I had safety cables.

Thats something that few people ever think about in a theatre, what happens when the earth starts shaking. The midwest is suppost to have a "mega" earthquake within the next 50 years when the new madrid fault line finally hits. When that happens, better hope your in a theatre with safety cables (hopefully i'm in the middle of a corn field, why I would be in a corn field, I dunno, odds are I will be strapped to a focus track or god forbid in a genie at the time).
 
If a huge earthquake hit the midwest, having safety cables would be the least of my worry

Can't hurt though. I was just trying to bring out the point that you always design for the worst case scenario, and people usually forget about that. Its one of the reasons that the x10 factor gets built into everything overhead If a quake starts and because there was safety cables on every fixture and it gives an extra 30 seconds of time before the safety's fail, then they did what they needed to do.
 
Yeah quakes are something we are very aware of out here on the West Coast. Personally after that experience I will never hang an instrument without a safety. It's not worth it.

Here's the rest of the Earth Quake story... I had 150 high school kids in the little theater (a very small proscenium space with one pipe over the audience and two small ladders on the side. Some one from the English department had booked this bizzare modern poetry reading that involved live soundeffects being created old radio show style while the poet read (it was crap). As the earthquake began there was this low rumble for about 5 seconds before it really started moving. Afterward, students thought it was just another sound effect. Then it really started rocking and the power started flashing on and off. In retrospect it was oddly funny. The theater was silent... then the lights would go out and everyone would scream... then the lights came back on and all you heard was panting of the student catching their breath. This cycle repeated on and off about 4 times before the quake ended. It was like being inside a horror film. The whole time I'm hiding in the doorway to the booth and listening to all my instruments smashing together praying the safety's don't fail.

When it was over we fortunately had power and simply exited out a side stage door to the parking lot as we had practiced in the past for drills... yes along with fire drills we have earthquake drills.

So here's the funny part. The teachers left with their students and I'm standing there looking at the poet and the sound effects guy. I fortunately didn't have a class that period. So I said, "there's no way we are getting everyone back in the building anytime soon, you might as well go home." So they pack up their stuff and we head out to the parking lot, me leading the way in a procession of hauling boxes of stuff. As we come down the sloped driveway into the parking lot the entire school is watching me packing out a bunch of boxes with a couple of strangers following. We all had a huge laugh as I started hearing students calling out... "Hey he's quitting!" "Can't take a little shaking?" "That's it I'm out of here." It was all very amusing.

On the serious side I didn't even loose a single sheet of Gel. There was some minor damage to plaster in the large theater but everything in the air was still there... although it needed a refocus.
 
:!: First thing is what is the correct way to lock of a c-clamp? I've never heard this topic discussed. What is correct/incorrect?

Hanging a light on a horizontal position (position is parallel to deck):
1) Place open C-clamp on pipe
2) Tighten c-clamp to finger tight
3) Attach safety cable
4) use wrench to tighten c-clamp about one half turn (this is especially critical if you are using aluminum truss as it is more malleable). You don't need to tighten the clamp more than enough to hold the fixture without moving. You will damage the position and weaken the c-clamp.​
To strike the light follow those steps in reverse.

To hang on a vertical position (i.e. a boom):
Hopefully you have sidearms, but the idea is the same. If you are using sidearms then you should attach the sidearm without the light on it.
1) Attach C-clamp to boom
2) tighten C-clamp to finger tight
3) use wrench to tighten about one half turn (as above)
4) if you are using a sidearm you should now place the light (with T-Bolt) on the sidearm
5) since you took the C-clamp off the unit to attach the T-Bolt for the sidearm you should take the c-clamp and attach it to the boom above the light. Now you have a point you can put the safety around. If you aren't using sidearms then you should use a spare c-clamp for this purpose.​
 
Hanging a light on a horizontal position (position is parallel to deck):
1) Place open C-clamp on pipe
2) Tighten c-clamp to finger tight
3) Attach safety cable
4) use wrench to tighten c-clamp about one half turn (this is especially critical if you are using aluminum truss as it is more malleable). You don't need to tighten the clamp more than enough to hold the fixture without moving. You will damage the position and weaken the c-clamp.​
To strike the light follow those steps in reverse.
To hang on a vertical position (i.e. a boom):
Hopefully you have sidearms, but the idea is the same. If you are using sidearms then you should attach the sidearm without the light on it.
1) Attach C-clamp to boom
2) tighten C-clamp to finger tight
3) use wrench to tighten about one half turn (as above)
4) if you are using a sidearm you should now place the light (with T-Bolt) on the sidearm
5) since you took the C-clamp off the unit to attach the T-Bolt for the sidearm you should take the c-clamp and attach it to the boom above the light. Now you have a point you can put the safety around. If you aren't using sidearms then you should use a spare c-clamp for this purpose.​

I always pre-rig the side-arms, speeds up things in the air. Also, for booms I usually right the entire pipe on the ground and stand the pipe up (with the boom base attaches the entire time. I usually don't like to do that if there is a fixture over 9' off deck.
 
When I hang things vertically I tend to really lock 'em off, as we don't safety them in that situation, so I've always figured it's better to mess up the pipe a little, to make sure it really stays on there.
My concern with sidearms is that in order to pan, you have to loosen the bolt on the yoke. I personally like to have an instrument secure when focusing it. I personally only like loosening the bolt on the yoke when it is on the ground.
On the positive side of things though that is the procedure I use when hanging an instrument (fixture? I still don't know what I should be callin' 'em),

Why not safety them? So it slides down the pipe several feet before it catches on something horizontal... still better than falling to the floor and killing someone.

Instrument vs. Fixture... I consider both acceptable and think that it's mostly one of those regional things like Gaffer vs Gaffa
 
When I hang things vertically I tend to really lock 'em off, as we don't safety them in that situation, so I've always figured it's better to mess up the pipe a little, to make sure it really stays on there.
My concern with sidearms is that in order to pan, you have to loosen the bolt on the yoke. I personally like to have an instrument secure when focusing it. I personally only like loosening the bolt on the yoke when it is on the ground.

This is exactly why C-clamps fail. If you "really lock 'em off" then you are putting the force on the clamp that is what weakens it. When using a sidearm, why is your fixture any less secure than when using a c-clamp? Unless I can't the yoke bolt of a c-clmap loose I never touch the "jesus" bolt because as soon as you start playing with it, it breaks. If you use a sidearm with a t-bolt it is no different then loosening the yoke bolt of a c-clamp. This is besides the fact that it is so much easier to focus a light that is on a sidearm rather than hanging off a boom by it's yoke.

An of course, I with gafftaper on this, why not safety them? It takes a whole 30 seconds to throw an extra c-clamp on a boom and safety all the lights that will reach to it. Sure, if your light is 6 inches off the deck at the bottom of the boom I can see not using the safety, but if you are any higher than the length of the safety you should be using it.

I'll see if I can grab a quick photo of one of my booms so you can see how I safety them.
 
Secondly, I don't follow about the chinese c-clamp. Would you mind elaborating on what it is?

Charc there is a lot of low quality gear being sold here coming from overseas. If you are buying from a reputable dealer don't worry... you are getting good c-clamps. Just don't go on e-bay for the cheapest c-clamps you can find.

[Hijack] It's a lot like buying chain, shackles, and other gear for overhead hanging. If it doesn't say made in the US and have the name of the company that made it don't buy it. If you need chain the rule usually is don't go to the hardware store go to Sapsis' or Fehr bros. website... or your local theater dealer. An exception to this has oddly appeared at my local Home Depot. They now are carrying a variety of Shackles and quick links made by Lehigh... which is a decent American made brand. But you always want to be careful and NEVER want to just buy the cheap Chinese chain sold at the hardware store. It may fail and that is a VERY bad thing. [Hijack ends]
 
Charc, I think Icewolf is calling the main bolt that connects the yoke to the c-clamp the "Jesus bolt". I've Never heard the term "Jesus bolt" but it makes sense to call it that and it also made me laugh a little. I took it as simply you don't mess with the bolt that is holding the instrument in the air unless you absolutely have to. Always use the small bolt up on the side of the c-clamp.

His point being if you have a side arm that has a large "Jesus Bolt" and the small side bolt on it, moving it is just as secure as hanging it on a C-clamp... but it's a lot easier side mounted than working with just a c-clamp.
 
Charc, I think Icewolf is calling the main bolt that connects the yoke to the c-clamp the "Jesus bolt". I've Never heard the term "Jesus bolt" but it makes sense to call it that and it also made me laugh a little. I took it as simply you don't mess with the bolt that is holding the instrument in the air unless you absolutely have to. Always use the small bolt up on the side of the c-clamp.
His point being if you have a side arm that has a large "Jesus Bolt" and the small side bolt on it, moving it is just as secure as hanging it on a C-clamp... but it's a lot easier side mounted than working with just a c-clamp.

Actually, by the yoke bolt I mean the bolt on the c-clamp that connects to the yoke of the instrument. I am kind of surprised that it has never come up on the board before, but by the "Jesus bolt" or "F#*k-me-nut" I am referring to the little square nut on the side of the c-clamp whose official name is the pan-lock. I have always heard this little nut called this on account of it is so easy to break it off, which often causes much cursing. Hence why I avoid it unless needed.
 
Ok, in some ways that makes more sense and in some ways it doesn't. Yeah I've seen those pan-lock bolts broken off too. But as long as you don't crank on them they should hold just fine. In fact it takes very little force to get it to lock and unlock properly. I don't buy the idea of using the main yoke bolt instead of the pan lock bolt. I keep those yoke bolts clamped down tight and don't mess with them. I train all my students to just lightly tighten the pan-locks... and I haven't had any major problems yet.
 
Ok, in some ways that makes more sense and in some ways it doesn't. Yeah I've seen those pan-lock bolts broken off too. But as long as you don't crank on them they should hold just fine. In fact it takes very little force to get it to lock and unlock properly. I don't buy the idea of using the main yoke bolt instead of the pan lock bolt. I keep those yoke bolts clamped down tight and don't mess with them. I train all my students to just lightly tighten the pan-locks... and I haven't had any major problems yet.

I guess it is a difference in how we were taught. As this is how I was taught in college.

Partially I think it has to do with how sensitive the pan-lock setup is, if you open it and close it enough times and it is consistent on who is doing it, the shaft that connects clamp to yoke gets damaged enough that you have to find just the right place to lock it down so that it doesn't wobble.

Then, consider being 24' in the air in the dark fumbling for a nut to move the light, it is a lot easier to grab the big one. If you are still using the original bolts from the c-lamps you should have plenty of threads that you would have to make about 15-20 revolutions to get it out. So is the light going to come down if you use that to focus, probably not, unless you are talking on your cell phone on top of the 24' a-frame extension ladder not paying attention (shame on you) which is when that safety cable would be a good thing.

I haven't (knock on wood) had a light fall on any shows that I have worked on. I have seen what happens when they do, thanks to someone kicking a light they were striking off a catwalk. It was an honest accident and no one was hurt, and it wasn't a show I worked on. Of the the other professionals I have worked with, I can't think of one who used the pan-lock for it's purpose.

Is it a big deal, probably not. If you feel safer doing things the way you were taught then you should do them that way, and not the way that a person you have never met says. I find it very interesting, a lot of things that I was taught in college from how to build a flat or platform to how to rig flying set pieces or practicals is just the ideal. You can walk into so many theatres and everyone will do the same task differently. Once I got out of school and saw this I started asking why, asked the TD why they did things one way when I was taught a different way. The answer usually is: "this is how I was taught" or "this is the way this theatre has been doing this for as long as anyone here can remember."

Wow, so I rambled on a bit there. I guess, the point is that I am not telling you that you are wrong or unsafe, and I don't think that you are telling me that. Differences in education and technique breed different ideas. The key, I suppose is that as long as you are aware of the risks of whatever way you choose to do something, you wll be able to do it safely.
 
Sorry I haven't responded to the questions. By "Chinese", I literally meant that they are made in China. The Jesus nut is a little plastic winged thing that breaks off quickly and the metal is soft cheap pot metal. When they are over tightened, they break very easily. They are heavy and look like the more expensive ones, so it is easy to get them confused.

I agree that I try my best not to mess with the Jesus nut (or whatever you want to call it). That is why I like the mega clamps. I use megaclaws on the movers and megaclamps on the conventional's.

As far as putting safties on sidearms/boom bases, etc... it is more difficult. I have seen people clip safties together and run them down from the electrics to the fixtures on these bases and sidearms. It is a personal choice on how to do it. I often mount movers to a pipe and base and have them at the back of the stage on in the wings. I clip the safety to the top of the pipe, or I have a few of the "O" rings that thread on the top of the pipe. I would hate to have a mover fall, or slide down it.
 
That is why I like the mega clamps. I use megaclaws on the movers and megaclamps on the conventional's.

So I've been looking at Megaclamps... new theater, why not start with all megaclamps instead of basic C-clamps? The price is only a couple bucks more. Anybody not like megaclamps?
 

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