When should you remove a safety cable from a light on the rig?

[paul roberts]

I was taking some lights off a rig recently for maintenance and left the safety cable attached until the last moment, I was told off by my manager that this was incorrect and not safe, I said surely it makes sense to keep it on in case it falls whilst I was loosening the coupler, as I help teach students I need to know correct procedure, I don't feel he is right on this occasion. The light I was taking down was a small spot.

 

[John Palmer]

Hello Paul,
First, I am glad that you are thinking so actively about safety. Keep it up!
Typically, I remove the safety cable before I loosen the clamp. With heavier lights, it can be very difficult to undo the safety while supporting the weight of the fixture. This can be worse if you are on a ladder or in a lift. The process of jockeying the fixture to where you can hold it and undo the safety might put you in more danger of losing your balance.
Take a few moments the next time you are working and see which way makes you feel more comfortable and puts less strain on you.
For hanging fixtures: put lamp on pipe and tighten clamp, clip safety, open shutters or set to spot for fresnels, cable fixtures, put color in, walk the whole pipe when complete and double check tight/safety/shutters/color completely in.
For stripping, follow reverse order.
I hope that helps you out a bit. Keep asking questions and stay safe!
Take care,
John

 

[Jayme McColgan]

if I'm working with lekos or fixtures of the sort I tend to undo the connection, then loose the fixture so it can come off, then I will undo the safety and take the fixture down.

sometimes I will undo the safety before I loosen the fixture and I will hold the clamp to the bar while I loose the bolts.

 

[SteveB]

Ditto Jayme's method.

If the pipe is on the deck, presumably there's nobody underneath ?, so you could take off the safety at any point.

If working overhead, I'll still take off the safety before I loosen the clamp, as I need two hands to remove the safety.

 

[robmerow]

Agreed - before loosening the clamp. This gives you two hands to handle the fixture and two hands to attach/detach the safety.

Safety cables are a funny thing that way... By far the most likely time to need a safety cable to prevent a falling light is while you're hanging or unhanging the fixture - the exact (and only) times that you can't possibly have it attached.

 

[JD]

Well, one would assume that when you are up there changing a fixture there is no audience in house and no crew member should be underneath you as even a dropped wrench can be pretty dangerous. The primary reason for the safety is to prevent people from getting clobbered, the fixture and floor damage is secondary. For awkward heavy fixtures, I like trigger clamps. As for the order of disassembly, I would think trying to balance a heavy fixture or mover while trying to unclip a safety may actually be more dangerous.

 

[gafftapegreenia]

Traditional c clamps fail most often when being tightened, so it's most important to attach the safety after the clamp is finger tight but before you put a wrench on it.


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[gafftaper]

Traditional c clamps fail most often when being tightened, so it's most important to attach the safety after the clamp is finger tight but before you put a wrench on it.

Agreed. The c-clamp is most likely to fail when being tightened. So the cable needs to be on before you apply the wrench.

When hanging the fixture:
Hang the fixture on the pipe and finger tighten the c-clamp so the fixture can't come off the pipe
Attach the safety cable
position and tighten the c-clamp

When removing the fixture:
Remove the safety cable
Loosen the clamp

 

[GreyWyvern]

Agreed. The c-clamp is most likely to fail when being tightened. So the cable needs to be on before you apply the wrench.

When hanging the fixture:
Hang the fixture on the pipe and finger tighten the c-clamp so the fixture can't come off the pipe
Attach the safety cable
position and tighten the c-clamp

When removing the fixture:
Remove the safety cable
Loosen the clamp

This is basically what I have always done. The difference is, when removing a fixture, I will loosen the clamp to finger tight, stow my wrench, remove safety cable, then loosen the clamp the rest of the way to remove the fixture.

 

[RonHebbard]

Agreed. The c-clamp is most likely to fail when being tightened. So the cable needs to be on before you apply the wrench.

I've only had three cast iron C-clamps fail in my life.
Two failed gracefully with warning cracks.
The third exploded suddenly and violently, dispatching my glasses to the floor, bloodying my upper lip and nearly costing me an upper front tooth. I was foolishly straddling the upper hand rail of a Tallescope and working alone at the time. DARNED glad I'd already installed the safety cable prior to applying my ratchet. As has oft' been said here, I've learned best from my mistakes.
Toodleoo!
Ron Hebbard.

 

[SteveB]

This is basically what I have always done. The difference is, when removing a fixture, I will loosen the clamp to finger tight, stow my wrench, remove safety cable, then loosen the clamp the rest of the way to remove the fixture.

If I'm removing a bunch of conventional fixtures from a pipe on the deck, I will pull power and stow whip and loosen clamps to finger tight, on a bunch of fixtures (or all). I'll then remove all safeties, then fixtures. This way I'm not dragging my wrench out of my pocket repeatedly. When you have Clancy Power Assist winched electrics, I'm never dealing with - strike a few units, drop weight at loading galley, repeat. It's nice.

 

[Les]

Agreed. The c-clamp is most likely to fail when being tightened. So the cable needs to be on before you apply the wrench.

When hanging the fixture:
Hang the fixture on the pipe and finger tighten the c-clamp so the fixture can't come off the pipe
Attach the safety cable
position and tighten the c-clamp

When removing the fixture:
Remove the safety cable
Loosen the clamp

I use this same method. When removing conventionals, I try to hold on to the yoke with one hand while loosening the clamp with the other. Once it's free, you can just lift the fixture off the pipe with the hand that's already on it. This makes things move quickly, especially if you're working through a bunch of fixtures.

One other note is to always make sure the clamp is all the way on the pipe before you tighten it. This will help ensure that things don't get bound up or suddenly "fall" in to place once you put a wrench on it. The pipe should be snug against the crook* of the c-clamp.

*Not sure if I just made up this terminology.

 

[lwinters630]

I use this same method. When removing conventionals, I try to hold on to the yoke with one hand while loosening the clamp with the other. Once it's free, you can just lift the fixture off the pipe with the hand that's already on it. This makes things move quickly, especially if you're working through a bunch of fixtures.

One other note is to always make sure the clamp is all the way on the pipe before you tighten it. This will help ensure that things don't get bound up or suddenly "fall" in to place once you put a wrench on it. The pipe should be snug against the crook* of the c-clamp.

*Not sure if I just made up this terminology.

Yes , crook is correct.

 

[danTt]

I tend to safety last/unsafety first unless I'm working in a position where I'm either concerned about the light going on the pipe (reaching way out to hang a light--sometimes it easier to hang close/safety and then slide it on the pipe), or in air with people or expensive things below me that make me feel extra safety is prudent.

Hanging on the deck though, or banging through a pipe grid, I want to prefocus the light in the proper direction when I hang it, and it inevitably seems like if I safety before doing so I'll end up needing to redo the safety, regardless of how far ahead I plan.

I can't agree with @SteveB enough though, when hanging a batten of lights "assembly line" is definately the most efficent way. Put all of your lights on finger tight, then go through and wrench tight, then undo pigtail and prefocus, then safety and pull shutters. The less you do each time the easier it is to streamline, and you're not fishing your wrench out at each light and then stowing it again.

 

[cdiamondz]

My procedure follows as:
Place clamp over pipe
Hand tighten screw
Safety
1/4-1/2 with wrench
Setup the rest of the fixture
If hanging more than 2 fixtures, do each step to all fixtures after putting clamp on and tightening it with your fingers.

I reference my newbs to this site about hanging fixtures, and it has a lot of other information as well: www.stagelightingprimer.com/index.html?slfs-fixtures.html&2

 

[BillConnerFASTC]

JD hit most important point - no one under the work while doing this or other work overhead. And if there are people in the area around the work, hard hats. Its only about protecting people, not property. The total cost of all the safety cables in the world - materials and labor - I'm sure is far, far greater than the cost of all property damage resulting from a fixture or c-clamp or accessory that failed.

 

[DELO72]

This is basically what I have always done. The difference is, when removing a fixture, I will loosen the clamp to finger tight, stow my wrench, remove safety cable, then loosen the clamp the rest of the way to remove the fixture.

And right here is the winning answer! It leaves the safety cable attached for the maximum amount of time, allowing it to fulfill its role.

 

[GoboMan]

It's also worth mentioning to not over-tighten c-clamps. I've seen an uncomfortable amount of c-clamps get warped outward due to them being too tight. The safety cable may keep the instrument from crashing down, but a 2-inch chunk of broken clamp will also do a world of hurt if it fell on someone's head.

My procedure is just like the one mentioned above: hang light, finger tighten while holding on to the light, safety cable, and tighten with a wrench. In most cases, and especially with hanging/adjusting moving lights, I have a crew of two people on the floor to keep the area below clear of people.

 

[ship]

My arm is usually around yoke and holding pipe at some point, but removing a safety cable after removing the clamp could be a safety risk. Here you are holding the fixture and than with one hand trying to remove its safety cable. I normally also do the loosten the clamp, un-clip safety cable than with wrench put away, do the finger loostening of the clamp. And of course nobody below.

 

[Jay Ashworth]

Well, the Kobayashi Maru answer is "take a vinyl coated 3 foot safety up on the cart with you, long enough to go around the batten, the fixture, *and where you're going to hang the light on the cart* (assuming you're using a cart/lift/whathaveyou), put it on, then take the other one off, and move the light.

(If anyone decides to try this, pay respectful attention to acceleration distance and vectors. )