# Weighting curtain for quick flys



## Anonymous067 (Jan 29, 2010)

Is it advisable or suggested to weight a curtain fly (in a counterweight system) so the curtain can be flown out very quickly?

I'm sure this is done in real life, but is it something that should be left to professionals, or can your average stand hand handle it so long as the weight is correct?


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## derekleffew (Jan 29, 2010)

Blah067 said:


> Is it advisable or suggested to ...



In my opinion, no. Intentionally making a lineset arbor-heavy may help overcome the initial inertia and friction to get the curtain moving, but will create additional problems stopping the movement and/or bringing the curtain back in. Plus, the rope lock should not have to maintain more than 50-75 pounds of imbalance, and that amount of weight is not going to make much difference in speed. If the curtain needs to fly out faster than a stagehand can manage, there are solutions such as rigging a double-purchase or automating it with high-speed winches.


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## Anonymous067 (Jan 29, 2010)

So is that how the pros do it? Just use motors instead of humans since they have unlimited budgets? Like when they fly real people from stage level to 30 feet up in <2 seconds?


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## derekleffew (Jan 29, 2010)

Have a look or two around this site: Fisher Technical Services, Inc..


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## photoatdv (Jan 29, 2010)

derekleffew said:


> Plus, the rope lock should not have to maintain more than 50-75 pounds of imbalance, and that amount of weight is not going to make much difference in speed.



I beg to differ on that. I intentionally added (or pulled) an extra 1/4 brick (17lbs) a few tries when I had fast ins or outs. It did make a pretty big difference with how fast I was able to fly it out. With that amount out of weight any competent flyman should be able to handle it safely (personally I use friction from my hand (wearing gloves) to slow it).

Of course as far as the locks consult whoever does your rigging inspections or the manufacturer if you aren't sure. Don't rig with fishing wire, no forks in outlets, ect. Standard warnings apply.


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## wolf825 (Jan 29, 2010)

Howdy, 
In a counterweight system the goal is to balance the weight so you do not have run-aways...and that what is being moved is done so in a always-controlled manner by the operator and can be moved by the operator safely. The operator then can move it at any speed manually as best they can.. If the operator is not 'strong enough' or 'fast enough' as implied, adding a second person to assist the flyman and double the effort and amount of hands moving the item would be the better safer choice then adjusting the weight on the arbor to put it out of balance deliberately. You can also, although not ideal, marry a second linset to that pipe for the second operator to use and operate together and then share the load between two arbors...but unless the item is bulky or exceeds the weight capacity, thats a pretty extreme thing to do just to gain speed.. I mean how fast do you need this curtain to move? Most fly moves happen in 3-5 seconds. Can the timing be adjusted elsewhere by when say the cue is called earlier etc? Is the Operator new and simply needs some practice to build confidence and strength/ability for timing? The OPERATOR of the flysystem should be the judge by the way of the weight and how it feels--if it is good for them...the weight should be tested by the operator prior to ensure it is in balance for their ability without difficulty or slippage--not adjusted by someone who is not operating the system or not testing weight for safety. 

When an arbor/lineset gets moving 'very fast' on a system that is not balanced or in this instance to fly out faster (arbor heavy) the potential for a single stage hand to lose control or injure himself in braking, or even have a runaway that cannot be stopped until it hits limit increases...and that can damage or destroy your system. An unbalanced item can shift when unlocked--and can knock items on the deck, or in the air the lineset may be adjacent to such as electrics and run into it because it began a swing motion when unlocked and things shifted suddenly...it creates an unstable element for safety in the theater operation. 

Additionally you then have a unit or lineset out of balance that then requires dogging or another method to secure & lock to hold that unbalanced weight when in and which can put stress on the lock and lines...and when the item is 'released' you increase the chance for a shifting of weight suddenly at the system in the blocks because it is out of balance, which can suddenly tighten lines operators may be holding and risk operator injury or damage. If an untrained stagehand or someone unfamiliar with the lineset being out of weight were to simply unlock without knowing--they could be caught off guard and lose control and damage/injury could result... 

Working unbalanced loads can also place stresses on the fly system, tracks, blocks, ropes, bearings and linesets that is adding more wear and abuse. Also keep in mind that it also varies whether you have a single purchase or a double purchase system in the amount of weight you are talking about here--a single purchase the weight ratio is 1:1 but in a double purchase system you have to double the arbor weight added for the item on the pipe in which you are trying to move (if you are lifting 150lbs, you need to load 300lbs of weight counter in a double purchase..where a single purch would be equal 150lbs loaded counter to move it--the weight issues being adjusted then become very significant to consider). If you alter that weight deliberately to toss it significantly out of balance, then you are significantly tossing out of balance and out of safety the system for proper operation. A balanced system is a safe system... 

While not 'perfect'--it does happen where in a system that a lineset may be a small degree off in balance--but this is usually no more then one brick off...either because the item is an odd weight which cannot be ideally matched, or because of the strength of the operator has adjusted it to their ability for (as you are asking) to give a very slight edge to fly out or fly in an item with speed--but such is only a very slight edge because its often only no more then a brick in difference...and the operator who does this should be a trained professional and who knows how to use and maintain control in a counterwieght system and fully understands the system operations. No lineset should ever be deliberately placed siginificantly out of weight to make gravity the second fly operator--gravity is not your friend in this case cause it does not take direction well.... And certainly not unbalanced to the point where the flyman only has to just open the lock and the lineset/arbor begins to move without assistance one way or another. The weight in a system should never be off by more then one brick or so..and your operators should all be trained to test weight in a lineset before they unlock or move an item to make sure nothing has changed. 30-40lbs difference is usually the max. Rope burns can reach 2nd degree stages easily, & injuries which can take layers of skin off down to the bone, crushing injuries and impact injuries from items from overhead are very possible...not for the amature. 

I would suggest you simply add a helper for the flyman and they both be trained in safe operation and they practice together many times before... A lineset can only physically move so fast and maintain safe CONTROLLED operation by the operator...and if for some reason the average 3-5 seconds or so is not 'instant' enough in a move time--then that may simply be one of the work-arounds a director or show will have to suck up and deal with. 

EDIT: I would also not suggest any 'old flyman tricks' either of holding the rope and jumping off a chair or stool to get an extra boost etc--that just adds to the injury potential for obvious reasons.. 


Just my thoughts on the subject....hope it helps. 

-w


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## venuetech (Jan 29, 2010)

you must have the system in balance but there are ways of getting the main curtain out quickly.


When you fly the curtain in go past the normal low spike, crumpling a foot or two of the curtain onto the floor, lock it off there. but never leave it in this condition this requires your constant attention.
with the bottom chain and a foot or two of fabric crumpled onto the floor you now have an slightly out of weight pipe ready to spring up.
with the momentum started by the spring should give you a quick out. as the pipe goes out it comes back into proper balance as it picks the curtain off the floor.

rehearse this with a number of observers.
pay special attention to the traveler block and lines.


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## photoatdv (Jan 29, 2010)

Thats actually a remarkable idea! Can't believe I haven't thought of it... I mean a curtain partially on the ground (starting with just a little, going to whatever weight that person can comfortably handle... that way it balances and I can grab it if they freak and let go (again... I love my gloves!) is how I train people on dealing with out of weight conditions. But I never thought about actually doing it for a show.


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## Footer (Jan 29, 2010)

This is why most flyman in IA houses are the 300 pound biker looking guy that can grab a line with one arm and get it moving to fullspeed with one pull. If you need to re-weight you pipes to get something moving, might be time to hit the gym or the McDonalds.


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## epimetheus (Jan 29, 2010)

Footer said:


> This is why most flyman in IA houses are the 300 pound biker looking guy that can grab a line with one arm and get it moving to fullspeed with one pull. If you need to re-weight you pipes to get something moving, might be time to hit the gym or the McDonalds.



I do believe I've worked with that particular flyman once of twice! Or maybe they just all look like that...


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## cprted (Jan 29, 2010)

Footer said:


> If you need to re-weight you pipes to get something moving, might be time to hit the gym or the McDonalds.


McD's is gross, hit the gym instead!

Blah067 said:


> So is that how the pros do it? Just use motors instead of humans since they have unlimited budgets? Like when they fly real people from stage level to 30 feet up in <2 seconds?


Unlimited budgets? In my wildest dreams!


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## Anonymous067 (Jan 29, 2010)

So does that mean bringing a curtain in farther than the normal in puts the lineset out of weight? I wasn't aware that the height affected the weight of the lineset.


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## cprted (Jan 29, 2010)

Blah067 said:


> So does that mean bringing a curtain in farther than the normal in puts the lineset out of weight? I wasn't aware that the height affected the weight of the lineset.


If you bring something like softgoods in below trim, as they pile up on the floor, the floor takes weight off the batten, thus putting things a little out of balance.


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## GreyWyvern (Jan 29, 2010)

Blah067 said:


> So does that mean bringing a curtain in farther than the normal in puts the lineset out of weight? I wasn't aware that the height affected the weight of the lineset.



The 1 or 2 feet of the curtain that is piled on the floor is weight that is not on the lineset at that point, the floor is taking that weight. So, yes, it temporarily throws things out of balance. However, as soon as the curtain leaves the floor, the weight is then transfered back and things are back in balance. Does that make sense?


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## derekleffew (Jan 29, 2010)

photoatdv said:


> Thats actually a remarkable idea! ...



Not necessarily. The visual of velour crumpled on the floor my be objectionable. Depending on masking trim heights, the track or batten may be exposed. Again, it puts undue stress on the rope lock and purchase line.

I've seen many main curtains rigged using lattice track that had no rope lock at all. When "in" they were perfectly balanced; when "out" slightly arbor heavy due to the weight of the lift lines.

See also

ship said:


> ... "What is meant by the term - bounce the Main?"
> 
> A) It's a term for when you dust it off by hitting it from the rear with a broom. Looks like the description from the front and thus it took as a term.
> B) It's a term for a style of closing the main drape where you close it all the way down and past it's normal position so it puddles up on the floor some than returns to it's normal position.
> ...


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## Anonymous067 (Jan 29, 2010)

GreyWyvern said:


> The 1 or 2 feet of the curtain that is piled on the floor is weight that is not on the lineset at that point, the floor is taking that weight. So, yes, it temporarily throws things out of balance. However, as soon as the curtain leaves the floor, the weight is then transfered back and things are back in balance. Does that make sense?



I suspected that. And yes, it does.

So last week, one of the boarder linesets in our theater was acting up, it wouldn't slide on the track. So I flew it in way past the normal "in" position (batten was at eye level, and we through a dust cloth down first to we didn't damage the curtain), fixed the track (didn't do this part, ask the SM), and flew it back out. I didn't fly it back out, but if I had, would I have felt it was very difficult or very easy because the weight of the curtain was on the ground and not the batten? Do those quesions make any sense?


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## MarshallPope (Jan 29, 2010)

Assuming you are single purchase, it likely would have been easier to take it out because, with part of the normal batten weight on the floor, the arbor would have been relatively heavier, causing it (the arbor) to want to came in when unlocked, raising the drape. The inertia gained at the beginning would help boost the drape as it went up, but it probably would not make much of a difference once it got five or six feet off of the deck.


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## MPowers (Feb 1, 2010)

No! NEVER intentionally unballance a lineset. 
1. If you have to unballance a lineset to make a line work fast enough, you are the wrong flyman for the job.
2. If you feel you must, you have the wrong mindset for a rigger. 
3. If a client/boss asks for a something that can not be done safely, your JOB as a rigger is to determine if there is an alternative in execution, materials or equipment and if not, to say NO. 

The potential for a single incident, (rope slips, miss your first stop grab, glove has worn and rips exposing your hand to the moving rope, glove is worn and rips jambing in the lock and pulling your finger with it, etc., etc.) to esclate into a catistrophic event are far too high. No effect, no gimick, no show, is worth getting someone hurt for. You might get away with it for a while, but in the end it will catch up with you.

I rigged my first show in 1963, I've never had a rigging related injury on a show since and I intend to keep it that way.

Michael Powers, Project Manager, ETCP Certified Rigger-Theatre
Central Lighting & Equipment Inc., Des Moines, Iowa Central Lighting & Equipment
[email protected], 515-277-4190x115


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## Morpheus (Feb 4, 2010)

wolf825 said:


> ...gravity is not your friend in this case cause it does not take direction well....



Yea, when was the last time you successfully told gravity to stop?

Yea, our main drape takes 2-3 people to bring it in FULLY (for when we need to move it to another lineset. We don't like moving it for that reason), yet one person can operate it normally no problem.


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## wolf825 (Feb 4, 2010)

Morpheus said:


> *Yea, when was the last time you successfully told gravity to stop?*
> Yea, our main drape takes 2-3 people to bring it in FULLY (for when we need to move it to another lineset. We don't like moving it for that reason), yet one person can operate it normally no problem.




Usually right at the point of impact is when gravity begins to listen to you...  



-w


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## MNicolai (Feb 4, 2010)

In another thread of yours, you mentioned how it took 6 people to fly a draw curtain in. The concept they've explained here is why. As more weight is transferred off of the lift lines and onto the floor, the system will act as if it is arbor-heavy, because once your draw curtain is on the floor, several hundred pounds that is intended to balance with the soft goods, now has to balance with the amount of tension you are placing on the purchase line.

I think many people here have taken the idea of taking the system out of balance a little too extreme. We use 20# bricks and 40# bricks. The closest you can ever hope to get your system in balance is within 10lbs accuracy. Even then, your load is ever-changing based on how much of your load is being distributed into the floor (if at all), and where your lift lines are. Your lift lines weigh something too, so a system that's in perfect balance will actually only ever remain in perfect balance when the line set is half of the way up. This is when half of your lift lines far factoring into your arbor weight, and the other half are part of your load weight. So even a system in perfect balance is actually already out of balance anytime the arbors are at the grid or at the floor. Taking the system a few extra pounds out of weight to make it move a little faster in a given direction is not going to result in any kind of sudden catastrophe. Each time you muscle in soft goods you're taking the system out of balance. Out of balance doesn't not necessarily mean out of control.

Part of safely operating rigging sets is being able to judge how fast is _too_ fast. Don't let your desire for a smooth scene change overpower your better judgements of what is or is not safe. The reality is if that scene change takes an extra two seconds, it's really not that big of a deal. And when out of balance remember that if you let go of the purchase line when the rope lock is disengaged, your line set will now begin to accelerate towards your grid. If this seems to accelerate too quickly to be safe, put the system more in balance.

There is some amount of discretion that the operator needs to take, not only when using rigging equipment, but in theatre as a whole. If you try something and it doesn't seem to be safe, don't let a director say, "Yes! That's the effect we want!" It may be the effect they want, but that doesn't mean it's safe to be performed every night. If this is really something you need, try it one-half brick out of balance and see how well it works for you. If you aren't the person who will be on the weight rail for the show, ask yourself if you consider that amount of imbalance something you would trust them or not to handle.

The difference between letting the soft goods pile up on the floor versus adding an extra half-brick is minimal. It allows the rigging set to accelerate just as quickly, and once up to speed, creates the same opportunity for disaster. *Granted, as soon as the soft good is off the floor, the set is back in balance and acceleration will slow somewhat*. The system being a couple pounds out of balance isn't what makes it dangerous though. What makes it dangerous is how the operator handles the load while in motion and at speed. If there is a person on the weight rail who is unable to safely handle a load being +/- 20lbs out of balance, they should not be at the weight rail in the first place.


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