Counterweight Fly Systems Technical Theatre Mr. Bartosh
What is a Counterweight System? A system of raising and lowering scenery and lights using a set of pipes, cables, ropes, pulleys and weights Allows for vertical storage above the stage in the heavens Also allows for utility work (bringing electrics in to hang/remove lights) Made from a series of line sets is one system of a pipe, all of the cables, pulleys (blocks) and rope
Where is this junk? Into the fly house The fly house is the space above the stage where scenery, curtains and electrics are stored when not in use Fly house is masked by what?
Loft Block Multi-Grooved Head Block Loading Gallery Grid Lift Line (Aircraft Cable) Trim Chain Arbor T-Track Purchase Line Locking Rail Batten Attachment Line Load Rope Lock Lock Ring Tension Pulley
Parts of a Single-Purchase Counterweight Fly System
Multi-Grooved Head Block Loft Block T-Track Guide Arbor Backbone Arbor Rod Collar locks Stageweight, Pig, Brick Lock Ring Rope Lock Tension Pulley
What are the pipes called? The pipe attached to a line set is called a batten On the Concert Hall stage, our battens are 63-0 long Our battens are industry standard 1-½ Schedule 40 Black Pipe The proscenium opening is 50-0 wide Why are the battens 13 longer than the proscenium opening?
Before You Move a Batten In a loud, clear and serious tone call the following EVERY time a batten is about to move (except during performance) 1. Heads up 2. Line set # 3. Coming in/going out 4. Location (US, DS, CS) 5. Make sure people on stage heard you with their response thank you
To Move a Batten After calling the batten: 1.Remove the lock ring and set it quietly on the rope lock 2.Unlock the rope lock by pulling the red lever away from the purchase line 3.Locate the batten you re moving and check to make sure there s nothing obstructing it s path to it s destination 4.Pull the purchase line closer to you to make the batten come in, pull the purchase line away from you to make the batten go out. 5.Lock the batten off when done. 6.Report any out of weight situations (the batten moves without you pulling the line) to Mr. Bartosh
Types of battens Single pipe batten (Type I)-Most of our battens One pipe suspended by lift lines (7 on our stage) Truss Batten (Type II)-Concert Ceilings 2 pipes joined together by steel connector bars Looks like a ladder on it s side Advantage? Holds more weight (and has a bigger arbor) Tri-Batten (Type III)-Electrics 2 pipes joined together and tipped at an angle, joined to a 3 rd pipe above (with a raceway for dimmer circuits) Used for electrics Battens used for lighting
Grid An open floor made of a grid of iron high over the stage (54ft on our stage) Perpendicular to the iron, loft blocks are attached to carry a lift line towards the stage floor. The open spaces in the grid floor are designed to allow additional pulleys and lines for special spot lines.
What s a Block? Loft blocks (or any block) is a pulley that s mounted in a fixed position. The wheel that rotates as the cable runs over it is called a Sheave
Fire Curtain Primary purpose of the fire curtain: To isolate the fire and save lives Always located most downstage Four ways to bring in: 1. Motor control (allows for raising and lowering) 2. Emergency pull handles (one way only) 3. Fusible links (activated by heat, one way only) 4. Electronic release (fire alarm system is activated)
Line Sets One complete set of counterweight components (batten, lift lines, blocks, arbor, purchase line, stage weights) The Concert Hall has 33 Line Sets 25 Manual Line Sets 8 Motorized Which are motorized? Electrics Concert Ceilings Fire Curtain (Separate system)
Motorized Line Sets A type of dead-lift system that employs electric winches designed for the purpose of lifting scenery 4 Electrics & 3 Concert Ceilings are motorized Controlled by motor control panel & pendant Pendant allows for 4 preset targets & current height Fire curtain separate & controlled SR Winch: A hand-cranked or motorized drum rigged with cable used to move scenery
Types of Counterweight Systems Single Purchase L.T.P.A.C. Concert Hall 1:1 ratio for both travel and weight 1 pound added to the batten means 1 pound must be added to the arbor 1 foot of travel for the batten means the arbor will travel 1 foot What does this mean the length of the T-Tracks must be? Purchase line is tied to the top & bottom of the arbor
Types of Counterweight Systems Double Purchase UTPAC Bass Concert Hall 1:2 ratio for travel and weight 1 pound of weight added to the batten means 2 pounds of weight must be added to the arbor 2 feet of travel on the batten means the arbor will travel 1 foot Provides a mechanical advantage Arbor tracks only have to be ½ as long as the batten travels Purchase line is tied to the head-block girder and anchored to the floor
Stageweights, Bricks or Pigs Made of pig iron or lead We have three sizes of stageweights: 10 lb 20 lb 40 lb
Trim Trim is the height of something above the deck (stage floor) In-Trim is the position of scenery as it should be when in use Out-Trim is the position of scenery as it should be when not in use
Spreader Plates A commonly misunderstood part of the arbor Primary purpose is to prevent the arbor rods from bending The spreader plates should be at the top of the brick stack on the arbor, and leave one behind every 2 feet in the stack
Muled Sets Used when fleet angles would exceed allowed tolerance Batten and arbor can be different distances from the plaster line Batten can be located in a place where an arbor cannot be Adds significant friction Requires special attention
To Rig Scenery to a Batten 1. Bring the batten all the way in to the deck 2. Attach the scenery to the batten using only rated stage hardware 3. Use shipping information, or good estimation to determine the weight of the scenery 4. Have a loading crew at the loading gallery add that amount of weight to the arbor 5. Check the lineset for balance 6. Repeat steps 4 & 5 until completely balanced 7. Use this method in reverse to remove scenery from a batten
Counterweight Safety (From Safety Memo) Complete silence when battens are moving or loading of arbors Make sure rail is lit Remain in control at all times, at least one hand on purchase line when unlocked Raise and lower battens slowly Do not force battens Do not bang the grid or deck Yell HEADS! In an emergency Do not sit on fly rail Only Mr. Bartosh or crew head talk to loading crew Line sets must always be left balanced and locked Rope locks will not hold out of weight line sets Safer to be slightly arbor heavy than batten heavy Make sure SL is clear before loading operations Always attach loads first, then weight the arbor Remove weight first, then remove loads