Rigging Certification -- Loader

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Rigging Certification -- Loader

• Purdue University Theatre
• April 8, 2006

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Introduction

• Counter Wait?
• Principles of counterweight systems
• How to knot hurt yourself and others
• Safe working practices on the weight rail
• Weight loading techniques and methods
• Help! Im tied up!
• Common rope types and uses
• Common knots and uses

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Counterweight systems

• Used to enable scenery to come from and disappear
  above the stage
• Simple in concept a system of ropes and pipes is
  used to move scenery up and down (known as
  flying in or flying out)
• Weight is used offstage to balance the weight of
  scenery onstage

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Counterweight systems

• Two common types of counterweight systems
• Single-purchase
• Double-purchase

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Single-Purchase Counterweight System
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Double-Purchase Counterweight System
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Counterweight systems

• Because single-purchase systems operate in a 11
  ratio, they must be able to travel the full
  distance of travel required of the batten (i.e.
  for a batten to descend 65' from the grid, the
  arbor must ascend 65' toward the grid)
• Because double-purchase systems operate on a 21
  ratio, they only need to travel half as far
  however, they need to stack twice as much
  counterweight, which means taller (and harder to
  load) arbors

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Counterweight systems

• The Hansen Theatre employs a single-purchase
  counterweight system
• 34 counterweight linesets
• 2 counterweight tab pipe linesets (running US-DS)
• 56' battens maximum live load 1450
• 5 lift lines with self-levelers
• T-track guided steel arbors maximum load 1850
• 2 counterweight (brick) sizes
• 1" (1/2 brick), 14
• 2" (full brick), 28

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Lift lines and Hand lines

• Lift lines
• Wire rope lines connecting the batten to the
  arbor
• Hand lines
• Provide method of operation of the lineset
• The hand line is essentially unrelated to the
  counterbalancing of the weight on stage
• A counterweight system can counterweight a
  batten without a hand line

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The Lock Rail

• The lock (locking) rail supports a series of rope
  locks, one for each hand line
• The lock is intended to keep a safely balanced
  batten in position
• The lock is never intended to hold a heavily
  unbalanced (out-of-weight) load while loading
  or unloading
• The lock is never intended to hold a heavily
  unbalanced (out-of-weight) load while loading
  or unloading

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Rope Locks
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The Arbor
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The Arbor

• The guide rods keep the counterweights in place
• The spreader plates prevent the guide rods from
  spreading apart should the arbor smash into the
  top or bottom stops if the guide rods were to
  spread, counterweights could fall out
• Spreader plates should be distributed every 2'
  (12 bricks)
• The lock plate prevent counterweights from
  falling out in the event of a crash, and should
  be locked down above the topmost counterweight

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Vocabulary

• Pipe weight
• The weight necessary to counterbalance the weight
  of the batten and the lift lines
• Pipe weight on each arbor is painted yellow, and
  should never removed from the arbor
• In-weight
• Refers to a state of balance on a lineset
• Out-of-weight
• Refers to a state of imbalance on a lineset
• Pipe Heavy
• Refers to an out-of-weight lineset which is
  heavier on stage (at the batten)
• Arbor Heavy
• Refers to an out-of-weight lineset which is
  heavier at the arbor
• Flying in (coming in)
• The movement of a lineset or scenery down toward
  the stage
• Flying out (going out)
• The movement of a lineset or scenery up away from
  the stage
• Heads
• Announcement used to indicate an uncontrolled,
  falling item

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The Loading Gallery

• The Hansen Theatre has two loading galleries, at
  approximately 50' and 60' above the stage
• When accessing the galleries (or any overhead
  position), remove all loose articles including
  hardware, tools, coins, wallets, or other items
  that might fall from your person
• All of the galleries, with the exception of the
  upper loading gallery, are accessible via
  standard stairwell

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The Loading Gallery

• Only authorized personnel are permitted on the
  galleries
• Unless wearing a fall-arrest harness and secured
  to the gallery, the guard chains must remain in
  place
• Never load or unload weight without being
  specifically directed to by the fly operator
• Always use proper calls when loading and
  unloading weight
• Always stack weights on the onstage side of the
  gallery
• Never stack weights higher than the kick plate on
  the gallery floor

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Cadence (or calls)

• When loading weight
• Fly rail loading 3 bricks, lineset 13.
• When unloading weight
• Fly rail unloading 4 bricks, lineset 3.
• When weight is loaded
• Fly rail lineset 12 at seven bricks above pipe
  weight.
• When weight is unloaded
• Fly rail lineset 7 at pipe weight.
• or, Fly rail lineset 7 now at 3 bricks above
  pipe weight.

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Proper Loading Procedure

• Announce commencement of loading to fly rail
• Loosen lock plate
• Slide spreader plates and lock plate up on the
  arbor and out of the way (secure with a metal
  spring clip)
• Firmly grasp brick with two hands, one on each
  side
• Always keep two hands on the brick!
• Slide brick onto arbor and around rear guide bar
• Lift near end of brick up and over to clear front
  guide bar lower around front guide bar
• Continue in this manner until proscribed number
  of bricks is loaded
• Slide a spreader plate down onto the stack after
  every 12th brick
• Slide spreader plates and lock plate down
• Tighten lock plate
• Announce completion of loading to fly rail

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Proper Unloading Procedure

• Announce commencement of unloading to fly rail
• Loosen lock plate
• Slide spreader plates and lock plate up on the
  arbor and out of the way (secure with a metal
  spring clip)
• Firmly grasp brick with two hands, one on each
  side
• Always keep two hands on the brick!
• Lift near end of brick up and over to clear front
  guide bar lower to rest on stack to the side of
  front guide bar
• Slide brick from rear guide bar and off the arbor
• Stack brick on the gallery (on the onstage side,
  never higher than the kick plate)
• Continue in this manner until proscribed number
  of bricks is unloaded
• Slide spreader plates and lock plate down
• Tighten lock plate
• Announce completion of unloading to fly rail

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Common Ropes

• Manila (natural fiber)
• Best natural fiber rope
• Because it is a natural fiber, it ages and loses
  strength
• Internal rotting
• Drying and dampening from atmosphere
• Stretching over time

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Common Ropes

• Three-strand twist (polyester, Multiline II)
• 2 times stronger than similar-sized manila
• Synthetic fiber is not susceptible to atmospheric
  aging
• Less likely to stretch than manila
• Because it is twisted like manila, any fiber
  breakage reduces the strength of the rope

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Common Ropes

• Parallel Core (polyester, Stage-Set X)
• 3½ times stronger than similarly-sized manila
• Continuous polyester fibers surrounded by a
  polyester jacket
• 95 of strength is in the core minor damage to
  jacket does not effect strength
• Synthetic fiber is not susceptible to atmospheric
  aging
• Nearly limitless lifespan

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Common Ropes

• Breaking Strengths for Manila, 3-strand twist,
  and parallel core

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Common Knots

• Effects of knotting
• Knotting a rope produces bends and shear
  stresses, and alters the geometric cross-section
  of the rope
• Knots thereby reduce the breaking strength
• Ropes will typically fail next to the knot
• Two common (and preferred) theatrical knots
• Clove hitch (used for tying to a rigid object,
  like a batten)
• 75 efficient (reduces breaking strength by 25)
• Bowline (used for creating a loop in a rope
• 60 efficient (reduces breaking strength by 35)