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	WPI Technical Theatre Handbook: Lifts
	Lifts Often times, a fly system is not available for use for flying lighting or audio equipment. Some venues, such as WPI's Alden Hall, do not have any permanent provisions for lighting equipment in the house. Thus, it becomes desirable to be able to fly a lighting truss in front of the proscenium by some portable means. Several companies produce portable lifts that can be raised and lowered by manual, pneumatic, hydraulic, or electric means. Lifts go by several names, such as Genie Lifts (a trade name) or towers. One such lift is shown in figure 4.7. Lifts have a set of feet that are adjusted to give stability to the structure. These feet typically immobilize the lift, as well as increase the footprint to reduce the chances of tipping. Once the feet are in position, the lift is typically raised enough for the load to be placed on it. Once loaded, they can be raised to the appropriate height for the task. Figure 4.7: A Genie Industries SuperTower being used to hold lighting truss. Usually lifts have a set of forks, akin to a forklift, for bearing a load. When placing a load on these forks, the load should be placed as close to the lift end of the fork as possible, to minimize the amount of stress on the fork. Often, two lifts are used in conjunction to raise a span of truss. When this is the case, it often helps to have a person stand back and keep watch over how level the truss is. Hand signals are typically used to tell the people raising the truss to stop or go. Figure 4.8: The forks of a lift. The top image shows the proper orientation of the forks. At WPI, Genie Lifts are often used to fly lighting truss. There are several important things to consider when using these lifts, as listed below: Make sure forks are placed on the lift properly. There are two orientations for the removable forks. The appropriate one is with the offset from the fork to the mounting piece to be facing down, as in figure 4.8 Never dynamically load a lift. This means don't bounce on it, and don't suddenly drop loads on to it. Most lifts have built-in braking schemes that will lock the extension arm in place if it is dynamically loaded. This means that the lift can not be raised or lowered without manually releasing the brake, which is a long and involved process. Be sure to lock the lift crank after lowering. The cranks on Genie lifts are ratcheting, but the ratchet releases when lowering the lift. This ratchet will not re-engage unless the crank is turned in the upwards direction. When a loud click is heard, the ratchet is re-engaged. Use of information in this document implies understanding and agreement with the copyright and terms of use. Specifically, no warranty is expressed or implied regarding the accuracy of the information contained within. YOU USE THIS INFORMATION AT YOUR OWN RISK. All trademarks are property of their respective owners. You must obtain permission from the author before using the contents of The Handbook for anything other than private use.	Table of Contents [Whole book in PDF 5.3MB] Contents Introduction Goals Sources Methods Conclusions Costumes Introduction Procurement Fabrics Color Patterns Fitting Rehearsal Clothing Design How to Begin Color Practicality Documents The Set Introduction Set Pieces Platforms Flats Stairs Rakes Other Structures Floor Coverings Construction Materials Tools Finishing Painting Types of Paint Mixing Paints Applying Paint Draperies Design How to Begin Documents Computer-Aided Design A Typical Set Construction at WPI Rigging Introduction Common Rigging Hardware Rope Wire Rope Thimbles, Wire Rope Clips, and Swages Shackles, Turnbuckles and Hooks Chain & Rapid Links Slings Fly Methods Non-Counterweighted Pulley Systems Counterweighted Fly Systems Lifts Chain Motors Flying Set Pieces Lighting Introduction Lighting Instruments Scoops Cyclorama Lights Parabolic Reflector Cans Fresnel Spotlights Ellipsoidal Reflector Spotlights Automated Instruments Color Color Theory Primary, Secondary and Complementary Colors of Light Light Mixing Practical Use of Color Glass, Gelatine and Plastics Dichroic Color Filters Patterns Dimmers Dimmer History Cables and Connectors Lighting Boards Control Design Washes Specials Cyclorama Lighting Color Lighting Angle Simulating Exteriors Lighting Design Paperwork Shop Order Instrument Plots Focus Sheets Computer-Aided Lighting Design A Typical Lighting Hang at WPI Audio Introduction Input Microphones Converting Sound to Electricity Directionality Analog Tape Digital Audio Tape (DAT) Compact Disc (CD) Mini-Disc (MD) Digital Samplers Computer Sound Cards Mixing Boards Signal Processing Equipment Equalizers Compressors and Limiters Noise Gates Effects Processors Output Power Amplifiers Speakers Crossovers Cabling and Connectors Line-Level Speaker-Level Automation Design Creating and Obtaining Effects Editing and Processing Effects Designing the Sound System The Input Section Signal Processing The Output Section A Typical Audio Setup at WPI Power Introduction Basic Theory Power Feeds Power Distribution Boxes Power Protection Important Considerations Special Effects Introduction Animated Costuming Smoke and Fog Pyrotechnics Acknowledgements References List of Figures Index About this document ...

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