Motorized Fly System

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Old-school riggers argue against fall protection by saying people who rely on it get sloppy, and to simply hire good riggers who won't fall and not amateurs. Everybody has now sipped the lanyard Kool-Aid and we've dumbed down high rigging.

Adding lanyards so that when riggers fall, and it can happen to any rigger, they are stopped in a safe manner doesn't dumb anything down but makes rigging safer. I'm not convinced these restrictor locks make anything safer. a counter weight system is designed to be human powered, having a lineset locked off for a show 1000 Lbs out of weight doesn't sound safe to me and restricts what i can do. Also what scenario do you need a lineset locked off that much out of weight?
 
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I'm sorry but I still disagree, you brought up a good point about cost though. Honestly it seems like you are throwing money at a brick wall and seeing what sticks though. Most schools brand new or even renovating cannot afford these restrictor locks. Hell they can barely afford to put lights in the space. First things they skimp on is always audio, lighting, and then fly systems, In that order. Well they've pretty muched cashed out what they can from the audio and lighting, now that fly system looks like its gonna be a dead hang because they can't afford to add the arbors and hand lines, let a lone the rope locks.
 
I'm not convinced these restrictor locks make anything safer. a counter weight system is designed to be human powered, having a lineset locked off for a show 1000 Lbs out of weight doesn't sound safe to me and restricts what i can do. Also what scenario do you need a lineset locked off that much out of weight?

What more do you need to be convinced? A 50lb lock cannot prevent a runaway in either direction. A Restrictor will prevent runaways in both directions.

Runaways are what we are trying to avoid. Restrictors prevent them. 50lb locks do not.

You can safely prevent a runaway with a 50lb lock plus a certain skill set, some sash cord or a broomstick, a comealong or tackle, and a sunday or prussick sling. But we've never successfully achieved that skill level enough to prevent runaway sets virtually every day in a theater somewhere in the US. You'd think we'd wise up.

Actually, "wising up" is coming in the form of schools being built without counterweight sets to eliminate the risk. I would rather have the CW system and manage the risk with Restrictors.

Isn't preventing runaways a worthwhile goal? Because what we've been doing for 100+ years has never prevented runaways on a near-daily basis, and is not going to suddently start working in 2015.

Restrictors make certain fast moves possible that would be difficult if the SM had to wait for a set to be snubbed, or where the flymen are so busy they cannot tend to the snubbing immediately.

A Restrictor adds possibilities, prevents runaways, and does not limit any move you want to make.

Say you want to strip a batten and slip the arbor down to bridge or floor level. With a 50lb lock you snub the purchase line, strip the pipe, unsnub the line and slip the arbor. It's exactly the same with the Restrictor except you do not set the lock before snubbing the purchase line; you just twist and snub.

In that scenario setting the 50lb lock accomplishes almost nothing anyway, so by not setting the Restrictor you're not losing anything.

But you gained something: in case of a problem, you can close the Restrictor and secure the set against a runaway. You can't accomplish anything by closing the 50lb lock on an imbalanced set, it's useless hardware at that point.

If a severely out-of-weight set sounds unsafe, then how much unsafer is it with a 50lb lock? Sometimes you can't reach the arbor and you have to manage severely out-of-weight sets some other way.
 
@Euphroe, I don't believe anyone here is disagreeing with you about the safety of a Restrictor lock in terms of operation. The debate is about what happens when students learn to rely on the Restrictor for that degree of safety, begin work in another theater, and fail to realize that non-Restrictor locks do not afford them that degree of safety.

If every rope lock in use today was a Restrictor or even most were, it wouldn't be so much an issue, but the Restrictor is currently a rare breed and unless price comes down drastically, likely to remain a rare breed. It's a promotion of what would be unsafe work methods under other, much more common circumstances. In schools, in particular, it's more troubling yet because students have such a narrow view of the world -- they'd be surprised to learn that not every other theater has the same types of rope locks as their theater does.

Another factor to take into consideration is that, though I'd expect runaways or close calls are not all that uncommon, we hear only about a few accidents a year where someone is substantially injured. While there are safer alternatives, such as motorized rigging with slackline detection and load monitoring, conventional counterweight rigging remains fairly safe. To that end, I'd not be surprised to learn more accidents happen in theaters annually from unsafe use of prop weapons or falls from ladders.

Taking into account the frequency of injuries in our industry, and comparing the risks versus rewards of Restrictor-type locks, I'm just not sure the risks outweigh the rewards. While that specific theater may have a reduced number of accidents and close calls, the prevalence of accidents and close calls may increase in the many theaters without Restrictor-type locks, who have people working there who have grown up with Restrictor-type locks.

Another thing to examine is I see more and more venues with motorized battens for electrics, and counterweight for general-purpose sets. Almost always, the most hanging from these counterweight sets are legs, borders, and drops. Maybe a mirror ball or a banner from time to time. I actually don't see many schools hanging scenery on their battens in excess of a couple hundred pounds. Certainly none that are going up several hundred pounds on a given batten, and anyone doing that level of production probably has a scene shop attached to the theater and proper supervision.

All things considered, I think that Restrictor-type locks in academic environments promote an unsafe work method in the broader industry that students are being prepared for, and that for that risk, not enough reward is to be had. For venues with motorized electrics for lighting (where the vast majority of reweighting would otherwise occur), the number of times a counterweight set is even used for actual scenery that may weight more than 250lbs is almost none, making Restrictor-type locks vastly overkill for the application.
 
Three thoughts-

Is there any data kept on runaways or other rigging accidents? All I've ever heard is anecdotal.

What happens when the restrictor gets loaded to 1,020#?

What kind of abuse do the head and tension blocks and purchase lines sustain being forced to carry 50-1000# loads? Are those retrofitted as well?


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When I hear of deliberately stripping electrics and then "slipping arbors" to the floor I have to clarify I do not tolerate absence of loading bridges. If you're installing counterweight (for general use) you must have a properly designed loading bridge. I think twice in maybe 150 projects I've renovated rigging systems without retrofitting a loading bridge, but did require a mule winch system and extra training and precautions. Not providing a loading bridge in new build should be criminal. I feel almost as strongly about gridiron access to make regular inspection and service much more likely. And if you can't afford the bridge or gridiron, you can't afford manual counterweight. Besides, a loading bridge is like the cost of one or two linesets, so no excuse.
 
...All things considered, I think that Restrictor-type locks in academic environments promote an unsafe work method in the broader industry that students are being prepared for, and that for that risk, not enough reward is to be had. ...
Do you feel the same about the SureStop™ Head Block ?
Couldn't one make the same argument against the SawStop | America's Number One Cabinet Saw | SawStop ? "Oh my dear deity, these poor, not properly trained, disadvantaged children are going to cut off all their fingers the minute they encounter a traditional saw."

Experts, care to expound on the merits/drawbacks of SureStop and Restrictor (and any others that serve similar purposes)? Disclosure: my experience in the early 1980s, with Tiffin's automatic ropelock that included a deadman pedal, was less than positive. Safe perhaps, but not enjoyable.
 
I think the Sawstop is different. Either you don't know it's there and you don't plan on it to save your butt, or you know it's there, either because someone bragged to you about it or you figured out the hard way. You also can't lean on the Sawstop to encourage your poor work practices because when it activates, it ruins the blade and costs a bit of money to replace. Whereas you can tap into the features of the Restrictor without ever knowing it, many times a day.
 
The SureStop looks interesting. It addresses the safety issue on the Euphroe side, but also makes everyone aware that an imbalance error has just been averted without slamming a pipe/kid into the grid/bridge.

I would still guess we're in cost-prohibitive-land for most schools.



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I like the concept of the SureStop because it doesn't (or at least shouldn't) allow you to work differently than a house that doesn't have them. It only should afford you some extra security.
 
It's been quite a while since I've worked on counterweight rigs so I defer to those who do this all the time. That said, I work with inexperienced people all the time in a place where adequate supervision is not always possible. Consequently, I am a strong believer in anything that makes it harder for somebody to hurt herself. The Restrictor appears to be designed to make it difficult to release a load that is badly out of balance. That might (and I stress the word "might") make it possible to develop bad habits that could get you hurt elsewhere. The same could be said for relying on any safety device that isn't universal such as seatbelts, airbags, parachutes, fuses, etc. Should I avoid using something in my venue that would make it safer? Isn't it the other venue's responsibility to provide the proper training for their space?

At the risk of heading off on another tangent, has any vendor ever developed and arbor with load cells that would sound an alarm when the load is badly imbalanced, like how commercial vehicles have to have a backup alarm? There are certainly times during loading and unloading when the system is knowingly out of balance. Maybe they should be beeping until the problem is resolved.
 
I also seem to remember a discussion at USITT a few years back of a theatre that had a counterweight system that used water to keep things balanced and sensed the weight loads and moved water as needed from a tank on the roof. Though I may be making this up entirely.


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Strad-in a new building I'd guess either the top lock or head block will cost about one in six or seven linesets so instead of 30-35 you'd get 25-30.

No, you probably should not retrofit a restrictor without some engineering analysis, and the t-bar is likely the weak point - just as it is the reason many people don't approve of using an uncle buddy. But that's a quick response, and I'd want a sealed drawing or calculations showing it.
 
> If you reduce the consequences of falling from height, have you encouraged people to act unsafely? That's silly.

Nope. In fact there's plenty of scientific evidence that risk mitigation just causes people - especially young people - to find news risks.

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This has been an interesting thread. MNicolai: I especially appreciate your thoughtful, substantive response, and the effort you put into both the substance and tone.

[playful tone on]

I would like to respond further, but am busy disconnecting the anti-lock braking system on my daughter's car. Since 100% of cars cannot be instantly changed over to ABS brakes, and she cannot tell the difference by looking at the car, it is unsafe for young drivers to have ABS brakes. They are a tool for teaching improper driving habits like jamming on the brake pedal.

Since young drivers cannot be introduced to ABS brakes, that innovation can never be introduced. All cars should be equally dangerous; the lowest common denominator governs.

[playful tone off]

Tiffin invests in building a safer product to mitigate a universally-recognized risk, and are basically told to jump in the lake; that their product actually creates a hazard by being too safe. This is the industry at its worst, discouraging innovation.

There's a century-long history of crashed CW sets. Few fatalities, but bent stoprails everywhere you go. IA crews struggling to bull sets, rope burns, scary moments that did not result in a hospital stay, but were bad enough.

Against this known history of accidents and near-accidents, there's a hypothetical possibility of an accident caused by a student who doesn't know the difference between a Restrictor and a paleo-lock. And the consquences of that accident will be no worse than the accidents that are already happening.

To the idealogues who insist after a century of failure that we should continue relying on teaching the "right way" with old locks:

It IS possible to use Restrictors but teach students to treat them like paleo-locks. To teach students not to trust them to hold more than 50lbs.

Because if you cannot reliably teach them the correct method with Restrictors, then you cannot teach them the correct method with paleo-locks either.

The difference is that with a Restrictor, you can teach them the traditional method, safely.

With the paleo-lock, we are *guaranteed* to have more accidents of the kind we've been having for a century or more.
 
Been thinking about this thread as it has been developing. It occurred to me that the one run away situation that I did witness could have been prevented had these rope locks been in place. Two students would have avoided ER visits and the costs of a rigging inspection and lineset replacement could have been avoided. So, that has me in favor of the Restrictor. Yet the situation could also have just as easily been prevented by better communication and education, so ultimate I remain internally conflicted.

Technology should never been viewed as a replacement for training and communication. I cannot stress this strongly enough. A lack of education and oversight is going to make any theatrical system dangerous, Restrictor locks or not. Is a poorly run venue or school safer with Restrictor locks? I'd argue marginally at best.

On the other hand, lets not fight technology when it can make our lives safer. I know that there is often a sense of tradition in Theatre, "if it ain't broke dont fix it" and "if it was good enough for me its good enough for them", but can we stop making our lives harder? Everyone makes mistakes, even the best up riggers and scenic carpenters, is it wrong to have more safety built into the system? I understand that the biggest fear is a sense of complacency that some might develop from using a product like the Restrictor or the Sawstop, but is the possibility of a *what if* scenario enough justification to stick to traditional tools? I think thats the heart of the debate here.
 
Can you actually back up this "crashes happen everywhere all the time" figure? I'm actually curious because you've seen evidence in every theatre you've been to it seems and in all the high schools I've been too I've been lucky enough to never see any of this. I'm not saying they don't happen, but I've visited probably 30 high school theatres and I've seen one with a batten that was bent but that's it.

Like strad asked earlier is there anywhere that we can find data on injuries and incidents out there or do we only have anecdote evidence to rely on?


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In maybe being backstage in 300 high schools, I think I've seen signs of two or three run-aways - deformed lock rail - and all on stages without a loading bridge. Keep it in balance, which it can be in nearly every high school situation as long as there is a loading bridge.
 

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