Counter Weight Flying

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This type of flying allows scenery to be counter balanced by a vertically travelling cradle which is attached to steel wires which run over a series of pulleys in the grid which all terminate on a fly bar. To operate the system control lines are tied off to each end of the cradle, this allows the operator to move the bar either in or out. By pulling the rope down the bar will move towards the stage and by pulling the rope up the bar will move towards the grid.


Single Purchase

“Single Purchase” simply means that to lift a certain load the same amount of “effort” is required.


With a single purchase counterweight set the same amount of weight is loaded into the cradle as is placed on the bar in order to “balance the set”, the weights become the “effort” required to lift the load rather than your arms which is good news for us compared to the hemp sets.


Note in the diagram below that the scenery is supported by 4 steel wires, which are attached to the top of the “cradle” which we now know holds an equal amount of weight.


The set is considered to be correctly weighted (balanced) when an operator can, let go of the control line and neither the scenery nor the cradle move.

The control line ( or "hauling line" as marked in the diagram) allows the operator to control the movement of the cradle, and therefore the scenery. The rope is moved in the same direction as the travel of the bar, i.e. when the rope is pulled down the bar will travel down toward the stage floor and vice versa. The cradle also moves exactly the same distance as the bar but in the opposite direction i.e. when the cradle moves up 6m the bar will travel down 6m, towards the stage floor.

I realise this is fairly hard to understand on paper but you will have the opportunity in the first weeks of term to try out the flying system and then refer back to these notes. I hope they will then become clearer.

SP-Counterweight.jpg



Double Purchase

The reason for using a double purchase system is usually lack of vertical space for the cradles. A Double Purchase system does not need as much height for the cradle, frame and runners as a single purchase system. In the Single Purchase set the cradle, frame and runners need to be the same as the full travel distance of the flying bar, in a Double Purchase system the cradle will only move half the travel distance of the flying bar.

The Double Purchase sets in the New Athenaeum are located above the dock doors into Room1. Since the runners could not come down to the floor level due, to the door, Double Purchase sets were installed.

In a Double Purchase set two lines support the load through a pulley on top of the cradle. Since each line has the full weight of the bar, double the weight must be added to the cradle to balance the set.

The simplified diagram below will, hopefully, begin to illustrate the relationship of weight and travel in a double purchase set.


DP-Counterweight.jpg DP-Diagram.jpg

The fact that the DP cradles are much bigger actually creates a problem when it comes to moving the bars with little or no weight on them. Since the bars are exactly the same as their Single Purchase neighbours the empty DP sets are naturally cradle heavy when unweighted and therefore do not exactly take double the weight of the flown piece at lighter loads.

Deading

Whether were flying using hemp sets or counterweight sets we need to be able to accurately fly the things on the bars to specific heights. Lighting need to know that their lights are returned to the height they were focused at if moved, masking may have two or three different precise positions during a performance and scenic elements and cloths during a busy show like a Pantomime can fly in and out numerous times.

So, we need to be able to mark the rope in a way that allows us to return the flying bar to the same position again and again, this is called “Deading” and is slightly different for Hemp than Counterweight

Dead marks at RSAMD consist of a broad band of white PVC tape and a narrow band of colour. The white is to help you see the dead in low light (performance) condition and the colour tape is for identification.

Deading.jpg

RCS Deading System

Generally the Grid Dead is marked with red in a 3 stripe (3 meters to grid), 2 stripe (2 meters to grid) and 1 stripe (1 meter to grid)


  • DO NOT Remove the grid deads
  • ALWAYS Remove old show deads after the production


Hemp Deads

Each hemp set has two cleats, an upper and a lower.

White and coloured PVC Tape marks are wrapped around each of the 3 ropes individually and normally lined up with the top of the flyrail; This tape would mark the “OUT DEAD” i.e. when the flying piece is flown out to its highest point so that it cannot be seen by the audience. The “IN DEAD” is slightly different, all 3 lines are cleated off to the lower cleat when the flying piece is in its IN position i.e. when the flying piece is at the height required by the performance to be seen by the audience. During a show the Flyman will only have to uncleat the line from the top cleat and lower the scenery until the lines are supported by the bottom tied off cleat. After the cue he will then pull on the lines to raise the flying piece until the OUT DEAD tape marks are lined up with the top of the flyrail and cleat off again.

Also when marking a dead on hemp rope, you do not need to exactly follow the above system of marks. The '1M' mark can be used for the out dead and you could do the same but with green tape just to highlight the in dead.

Counterweight Deads

Deading on the counterweight sets is much easier. We only have to dead one rope (the control line) and it is normally deaded just above the brake assembly as shown in the diagram above. Please use the system above to mark deads on the rope, using the same color ect.

There are also permanent “Grid Deads” on each of the counterweight control line ropes, these are marked slightly differently to avoid confusion and are always red and white. (we don’t use red for anything else) . These Grid Deads warn the operator that the bar is approaching the grid, they are marked as 3,2 and 1 red stripes as a countdown to the point where the bar reaches the grid. These marks alert you as to when you should be slowing down and stopping. The more you fly the more used to the system you will get and the better you will be at stopping on a dead. Hitting a Counterweight Bar off the grid is considered VERY bad practice and normally carries the penalty of buying everyone else in the vicinity a beer in the pub that evening.

Removing Deads

This is an extremely important and often overlooked part of the performance process. All show deads (not grid deads) must be removed at the strike. I have seen flying mistakes time and time again where a poor operator flys in a scenic piece to a blue dead, as it says on the fly cue sheet, only to be shouted at that the piece is out of position. What has happened is that a blue dead from a previous show has been left on the rope through lazyness and the operator has stopped at that instead of his own blue dead.

Please ensure deads are removed when they are no-longer needed.

Rigging

This is the Safe Sytem of Work for LOADING of Countwerweight Sets re-written September 2010. The term "floor manager" is used for clarity but this will normally be the Technical Stage Manager.

1. Personnel must include 1 floor manager, 1 fly person on flyfloor and 2 persons to unload cradle. A member of staff must be present in the venue.

2.. Hard Hats & Steel toe capped shoes must be worn by all onstage during this procedure.

3. The floor manager will instruct the fly person that the stage is clear to bring bar in until it is at a suitable height for attachment of scenic item. The floor manager watches at all times and gives clear vocal instructions to the fly person as the bar approaches the floor. Walkie Talkies should be used where possible.

4. When the bar is at rigging position the flyperson applies the brake and applies a rope clip. Once this is done the flyperson will inform the floor manager that they may proceed with the task.

5. The floor manager may then instruct the attachment of the scenic item, checking all equipment, attachments and fixing points.

6. Once the scenic item is attached and checked, the floor manager will request to the flyperson a specific number of weights to be loaded into the cradle. The flyman will pass this information to the Loading Gallery confirming the number or weights and cradle number. Stage crew may be required to maintain downward force on the bar to act as a counterweight against the loaded cradle either manually or by ropes slung over the bar depending on total weight of the scenic item.

7. Once the cradle is loaded the loading gallery will inform the flyperson that the cradle is loaded confirming the cradle number and number of weights. The flyperson will pass the information to the Floor Manager confirming the cradle number and number or weights.

8. The floor manager will then instruct the flyperson to remove the brake and clip and fly the bar. Again the crew may be required to act as counterweight until the weight of the scenic item is fully hanging on the bar. This will be the decision of the floor manager.

9. Once the scenic item is hanging on the bar the flyperson will adjust the weights if required i.e. add or remove a couple of weights at the flyfloor to ensure that the counterweight set is “balanced”.

10. Once the bar is balanced the flyperson will inform the floor manager who will then instruct further work plan.



This is the Safe Sytem of Work for UNLOADING of Countwerweight Sets re-written September 2010. The term "floor manager" is used for clarity but this will normally be the Technical Stage Manager.

1. Personnel must include 1 floor manager, 1 fly person on flyfloor and 2 persons to unload cradle. A member of staff must be present in the venue.

2.. Hard Hats & Steel toe capped shoes must be worn by all onstage during this procedure.

3. The floor manager will instruct the flyperson that the stage is clear to bring bar in until scenery is floating just above stage. The floor manager watches at all times and gives clear vocal instructions to the fly person as the bar approaches the floor. Walkie Talkies should be used where possible.

4. The floor manager then manually guides the scenery onto the floor. Depending on weight and personnel this may be manually or using ropes slung over the bar to ensure that the bar and cradle remain in balance at all times.

5. Once the loaded bar is in and the bar is at it’s lowest level, the floor manager will request that the fly person applies the brake and clip to the counterweight rope. The stage crew must maintain downward force on the bar to act as a counterweight against the loaded cradle.

6. Once the rope is secured and clipped the fly person informs the loading gallery and floor manager that the bar is braked and clipped. The floor manager then requests to the flyperson that all weight be removed from the specified cradle. The flyperson then instructs the loading gallery to remove all weights from the specified cradle. The stage crew continues to apply weight on to the bar until the procedure is complete and the loading gallery confirms that the cradle is empty.

7. When the cradle is clear of weights the loading gallery communicates to teh flyperson that teh specific cradle has been completely de-weighted

8. The flyperson confirms with the floor manager that the specific cradle has been de-weighted and the bar is safe to de-rig.

9. Once the bar is de-rigged, the floor manager communicate to the fly person that the empty bar can be flown out.

10. The fly person gives a loud warning shout confirming bar number and that the bar is about to be flown out.

11. The fly person should position themselves so as to have the best view possible onto the stage and begin lifting out the bar slowly until the bar reaches it’s “out position”.

12. The floor manager remains watching at all times during this move and gives clear instructions to the flyperson if required due to the flyperson’s restricted view

Grid

The highest area in the fly tower, this is where all the loft and header blocks send the steel wires which are attached to the cradle down through the grid floor to the bar.

When working on the grid you MUST empty your pockets and make sure any tools you need are attached to yourself or something that wont move.

The gaps at the edge of the grid area are filled in with mesh panels.

Please make sure that ropes run through the wire mesh are not rubbing.

Loading Gallery

This is where the cradle is at its highest point of travel and so is weighted here. The cradle is at the loading gallery when the 'Deck Dead' is level with the break on the fly floor. Please keep the weights stacked neatly and half weights in a separate pile (it makes it much easier)

Intermediate Fly Floor

Level between fly floor and loading gallery this area is used for balancing out double purchase cradles (since is is the half way point of the DP bar travel) and can be used for a variety of other purposes such as giving assistance with heavy hemp lines or rigging high level breast lines.


Fly Floor

Where all the fly bars are operated from.

Please keep the fly floor tidy. The Head of Flys for each show is responsible for keeping the fly floor tidy and in a safe working order i.e Tidying rope, clearing rubbish, using appropriate rope deads, clearly marking chalk boards with bar information and removing them after the show.

A copy of the Fly Plot and Fly Matrix for your show should be clearly displayed on the fly floor at all times the show is in fit up, tech/dress runs and performances.

Flying Bar

Metal bar onto which flown pieces of scenery, lighting, speakers, pyrotechnics etc. are attached to.

The wire ropes which are attached to the flying bar, travel up to the grid, go through a series of pulleys and attach to the cradle via Short, Short Mid, Long Mid, Long steel wire rope.

Cradle

Sometimes referred to as Arbor

A metal frame into which counterweights are placed to counter-balance the weight of a flying bar.


CounterWeights

Weights used to balance out heavy scenery which are placed into a cradle usually in two sizes 'whole' and 'half' weights. Whole weights in the New Athenaeaum Theatre are 12kg and Half Weights 7.5kg. Don't ask :-)

Control Line

The line which is hauled either up or down to move the cradle and move the flying bar.


Brake

The brake has the control line passing through it and when applied is designed to stop any movement in the cradle or bar however they are not designed to, and should never be, holding any of the weight.


Rope Clips

Metal hardware peices used as a secondary safety device when working with counterweight bars on stage. They are used by the flyman to grip the control line to itself. Commonly used during a fit-up or LX rig, the bar in question will usually be flown in to working height, then "braked and clipped" before the weight on the bar or in the cradle is adjusted.

Rope-Clip.jpg

Loft Blocks & Header Blocks

The header block is always the first block on the grid which the lines will pass through (directly above the flyrail), the pulley blocks which sit on the grid are loft blocks.


Hardware

Drifts

These are lengths of steel wire rope which are used to hold scenery to fly bars. Normally made up by a specialist company and supplied marked with a Safe Working Load and Declaration of Conformity Certificate.


Hanging Clamp

Hanging Clamp Small.gif

Double sided clamp with circular hole designed to fit round fly bar and hold scenery in place. These can be with the ring attached as in the picture or without.


Turnbuckle, Rigging Screw, Straining Screw

US Fed eye to eye.jpg

Double ended twisting screw which allows small altertions in the height and level of a flying piece by either raising or lowering it. Can have jaws or eyelets at each end or one of each. Diagrams shows "eye to eye"


Shackles

Used as a joining piece between drifts, turnbuckles and barrel clamps. Usually in two different types:

D-Shackle AB161077LG.jpg

Can only have force applied on each end of shackle. Good for straight up/down rigging.


Bow Shackle

Images.jpg

Can have force applied in several directions. Good for multi-angle/directional rigging.


Flying Irons

Flying Iron Small.gif

Attachement between the scenery and the drift, MUST be bolted through the flat and then attached normally to a straining screw which, in turn, is shackled to drift.