Safety Cables

propmonkey said:
i wrap our saftey cables twice around and i make sure i have one on each, i cant fly the pipe up unless theres one on each, though if the instrumnet has a hook like a source 4 or parellipshperes i try to use 2, one around the yoke and one in the hook.

Since we only have one for each instrument, I make a slip knot around the yoke and pipe and then clip the end on to the instrument.
 
propmonkey said:
i was taught to do 3 crimps not 2. and the loop on the connector side looks to small.


Ding Ding Ding!!! we have another reason this cable's unsafe. Two more rationals that it's unsafe to go.

This was the first reason I noted and very important.

Expert and amature alike should have noted this. Well done and if anyone disserves the gold star swag on this one you do.


Connector side size of loop has already been covered, this end of the cable is done in what you should note about it.



propmonkey said:
are you sure thats homemade? most of ours look like that(40+) we have some homemade ones(dont use much) that have copper nico sleves. we just bought 10 new saftey cables i wish we had more of them.

Hmm, copper nico slieves, hint hint hint. Now where did I read something about the type of Nico sleeve in use before for rigging purposes?
 
I just wanted to throw this out in case there are theaters that do not do this.

This was the first year that we have been able to purchase some barn-doors for our 8" fresnels. While we do safety all of our lights and satellite dimmer packs, we weren't sure whether it would be necessary to safety the doors. Just to be safe, we did (luckily).

A week later, our gym teacher... who could care less about the drama program and decided to offer bonus points to the student who kicked a ball and dented a fixture... was playing kick ball with his classes. A ball hit a barn door and knocked it out of the ... I don't know the technical term for them ... gel holders that hold the barn door as well. Had it not been safty cabled, it would have fallen 40' and landed on the head of one of the students lingering under the light baton.

I had a very long talk with our building principal about our gym teacher's attitude. They now play floor hockey during tech week.

I guess in hind site, had I hung footballs up there, he would have been more respectful... leading me to think that I should paint my fixtures brown with a couple of tiny :roll: white stripes in the center
 
Thats a really stupid thing to do, I'm surprised that even if your gym teacher didn't have any respect for the equipment or anything she would have realized that stuff could have fallen off of there and hurt someone.

~Nick
 
its intresting because when ever i buy used or new lights its not even an option to get it with out a saftychain it just shows up and has one same with used or new barn doors its not like its a law that they have to do this its just there standard way of selling equipment i think all distributers should do the same thing


JH
 
What type of gobo are you talking about? We use ones that fit into the front of our source fours but they are just little pieces of metal (circles with patterns like you say) and they have fallen out but they seem to only weigh a few ounces if that. So I'm just wondering which ones that you mean.

~Nick
 
those are what we have and i always saftey cable them. with the 6" barndoors we have i cant put a saftey cable on them.

on the left side, a few inches below the loop it looks like the cable is becoming untwisted.

but yeah i just collected all my extra saftey cables, of all the ones i have not in use(we cleared our pipes) 95% all look like that.
 
ouch ... what are you going to do about all those bad ones. I'm assuming cause theres no other pic you ment they looked like the orginal picture. I think some of the problem is that people don't realize that just because something looks good or like something they've seen in a picture that the little differences can have BIG effects like not having it crimped 3 times and not having the ends sticking out and such.

~Nick
 
Some barn doors for the Studio line have a wire frame to them whilch is easy to safety cable to but frequently needs improvement to the design to get the barn doors to retain position. I'll deal with that as long as it's easy to safety cable thru the wire. Others have a little steel loop sticking out of the fixture that should be sufficient to safety them. Otherwise, Yep, you got it, barn doors, top hats, even gobo rotatators or normal gobos if the fixture does not swivel and the gobo is at an angle, should if at all possible be safetied. Note that you don't in a absolute sense have to use a stock safety cable for this given the weight and you can clip to the main safety cable in having a shorter length, but otherwise given a fact that it could easily fall, some modification to the equipment should be a good idea in making it safe.

I also caution on being similar or being the same as the photo. It's possible that a safety cable made with copper nico sleeves that test properly with the go/no-go gauge, even if home made but in good condition (three "good" crimps still required as a huge thing to note) will be perfectly fine. Such practice is safe when constructed properly. Be cautious about what is other than manufactured equipment, but do not go into panic mode instantly unless it shows signs of bad practice immediately. Do a test - such a Go/No-Go plate even if you don't own the tool is cheap.

Given it's assumed that the photo clearly shows a aluminum oval sleeve crimped to the wire rope, it is evident that it is the #4 reason this safety cable is to be removed from service. Sorry but even if your hardware store stocks them and says it's the same thing, there is a large difference between the intended use of them that is useful for reinforcing a wood gate and what you use in shock loading or good practice. In the past I was a fan of aluminum crimps. A past post on stagecraft by Bill Sapsis brought the shock loading value to my attention. Since than I have not gone back.

There is however zinc plated copper nico sleeves on the market these days. Just because it's silver in color thus does not mean it's unsafe. If aluminum, and if absolutely necessary by budget to keep, use it for your barn doors. It has the same load rating as the copper sleeve, just does not do that well in a falling condition. Mark such cables say with a gaff tape banner on it that says it's usefulness or problem if on a absolute budget and otherwise safe. Otherwise and in general when a safety cable, (hint to the last two problems) if it shows a problem, don't just throw it out, cut it up so it can't be used. Same with carabeeners - I do mean them in this instance, or any other piece of rigging up to and including a spanset with holes. Even the hand line for the fly system cut up. If unsafe for you, you are still liable to an extent for something someone trash picks. This is not "Junkyard wars" in finding gear you might use to build a contraption with. (much of it - especially the brand new tires and $180.00 bearings are pre-requested and staged even if trashed or brand new in having to be safe as a note that's important.) You in theory know what you are doing. Some totally trashed pickup truck you might follow on the street some day that's overloaded with scrap metal on the other hand might have found your old rope and be using it up until the point a refrigerator falls on the hood of your new car. This is a minimum type of thing. Some kid might find your old rope or gear and choose to make a swing or climbing rope off it. Don't matter if you tossed it out or not, that kid falls, you are at fault legally and to even if innocent still in some way responsible. Cut that stuff up before disposing of it.

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I can't tell exactly, but are those carabeeners designed to take weight? I know EMS sells two kids, one for taking weight and one for using on a belt clip / lanyard or with keys. They looks very similar (I couldn't tell the difference besides price) so I'm guessing it would be very easy for someone who was making their own safetly cables to go for the cheeper ones not knowing that they wern't designed for that purpose. However, like I said I can't tell from that picture if they are the right kind for the job and broke anyway or if they were the keychain kind that was never supposed to carry actual weight.

~Nick
 
SketchyCroftPpl said:
I can't tell exactly, but are those carabeeners designed to take weight? I know EMS sells two kids, one for taking weight and one for using on a belt clip / lanyard or with keys. They looks very similar (I couldn't tell the difference besides price) so I'm guessing it would be very easy for someone who was making their own safetly cables to go for the cheeper ones not knowing that they wern't designed for that purpose. However, like I said I can't tell from that picture if they are the right kind for the job and broke anyway or if they were the keychain kind that was never supposed to carry actual weight.

~Nick

Each carabeener that is rated for use will have manufacturer's stamp and a load rating I believe in Kilo-Newtons. In addition to a UIAA or ? other standards of design compliance stamp. Because the key chain looks like one, that makes it dangerous to those that don't know better. In fact, there is no load rading on a key chain and beyond keys should never be used for other than that purpose.

"I'm guessing it would be very easy for someone who was making their own safetly cables to go for the cheeper ones not knowing that they wern't designed for that purpose."
Let me be very clear. Neither is designed for use other than in repelling or holding keys. Much less you should not use a carabeener for keys nor a key chain for repelling.

You should not be making safety cables with them or be using them for other than repelling and rope work. If you have a drop line to pull parts up to the grid, shure, if you have to repell down from the grid to get into a place above the set, sure. If you have fall protection on, yes - as long as steel and designed for that purpose. This is all repelling or similar. You do not attach wire rope to them, nor use them for safety cables.

The design and materials used for repelling gear are in no way similar to those used for rigging or equipment safety. Oval carabeeners have just as much weight on the gate as the other side and should be avoided other than for specific purposes in repelling. Aluminum in general is lighter but is also much more prone to damage. Where high strength or resistance to abuse is needed newer styles of steel should be used. The end tabs on a carabiner gate cannot hold much weight and can snap when exposed to forces between 500 and 2,500#. Carabiners get weak from repeated stress, once exposed to this or showing wear they need to be replaced.

While the steel snap hook with eye is also not the ultimate in design, it is however designed for this purpose, much less is much smaller and less expensive. One decent carabeener - much less one with some form of lock to the latch will cost many times that of a pre-built safety cable or any of the other components.
 
I understood that, but you also mentioned using a carabiner proper for safety cable. You were worried about a key chain used for safety cable as opposed to a carabiner.

I was saying that neither a key chain, nor a carabiner should not be used on a safety cable.

In re-reading your post, it's kind of confusing. While you mention taking weight and safety cables in the same paragraph, there is nothing you said specifically stating an intent to use carabiners for safety cables. Just a fear that someone would use the key chain type for them.

I apologize for jumping to this conclusion if that un-stated link I drew was not intended to be assumed.


The photo shows repelling carabiners that had their gates bend from use/abuse. They were cut with a Sawzall before being thrown out.
 

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