400) What is the maximum safe working load of 1/8" galvanized wire rope? 401) What is the approximate safe working load of a safety cable? 402) What is the difference in SWL between a double saddle cable clamp and a malleable clamp? 403) What is the percent efficiency of a drop forged wire rope clamp? 404) What is the percent efficiency of a aluminum Nicopress sleeve and why are they not to be used on stage? 405) What is the difference between SWLs for stage work and industry? 406) What is the safe working load of a single spanset in the choker arrangement around 1x1 truss? 407) What is the approximate sheer strength of a store bought 5/16" lag bolt? 408) What is the Safe Working load of a 1200# SWL Rope with a Clove Hitch in it? 409) What is Schedule 80 pipe? 410)Which pipe is not measured the same as the rest of the pipe: Schedule 40 black pipe, PVC, Pneumatic, EMT, RMT, Aluminum, Galvanized, or Schedule 80? 411) What is the difference between 1/4" NPT, 1/4" NF, and 1/4" NC nuts? 412) What is the approximate bolt grade of Aircraft Grade Alloy Bolts? 415) What is the purpose of washers in high strength fastening? 416) Is there a difference in strength between zinc and plain steel fasteners? 417) What would be the best washer for use when bolting to an I-Beam? 418) When a rope or cable or wire breaks, why does it not break at the point it is being pulled from, instead it breaks somewhere between 9 an 36 inches from it? 419) A Sling lifting 1,000 pounds is attached so to its load so it forms a 45/45/90° triangle between its two hanging points and the hook, what is the approximate load on each diagonal leg of the sling? 420) In general when hanging things, the steeper the vertical angle of the cable from the hanging point, the ______ the load is on the cable. 421) The proper way to un-reel wire rope or cable from the spool is from above or below? 422) In coiling a right-lay cable, wire, or rope, the proper direction to coil is clockwise or counterclockwise? 423) How do you “Mouse off” a shackle or turnbuckle? 424) What does “Never Saddle a Dead Horse” mean? 425) What are Legs, Boarders, Teasers and Tormenters, which is which and what if anything is the differences between the two general styles of drape? 426) What is stronger in rigging components, bent stamped steel, cast steel plate, or forged steel? 427) What is West Coasting? 428) What is the average or normal speed in feet per minute of our 1 ton chain hoist? 429) Are 1 ton chain hoists Polyphase, Induction, Synchronous, Split Phase, Capacitor, Repulsion, or Shaded-Pole motors? 430) What is a fire link, what is its load rating, and how long of a service life does it have? 431) What is Static Equilibrium in reference to a fly system? 432) Mechanical advantage is what divided by applied force? 433) What does the head block of a fly system do? 434) What knot do you use to tie off a hemp lineset to a batten? 435) What is the cable called a Sunday and what is it used for? 436) What is a knuckle buster and what is it used for? 437) Rope must be strong enough to support the load safely and absorb what three loadings for any particular application? 438) Broken internal strands of wire or rope is an indication of what? 439) A the groove of a sheave should be sized to support at least how much of a ropes circumference? 440) Explain resultant forces applied on a block. 441) On a beam, batten or truss with three evenly spaced supports on each end and the center, what is the percentage of load carried by the center and each end? 442) In general, moving the end supports toward the center of a load does what to the percentage of the load carried? 443) On a five lineset or post supported beam/truss/batten, which post(s) carries the most weight? 444) Grid floors have their deck planks/steel mounted parallel or perpendicular to the proscenium? 445) What is fleet angle, and how much is permissible? 447) What is the difference between an Idler Pulley and a Mule Block? 448) How do you tie off a line set to a pin rail? 449) On a double-purchase counterweight system, how many feet does the batten travel for every 1' of arbor travel, and how many pounds of counterweight are required for every pound of load? 450) Three reasons imported rigging hardware is never used on stage are: 1) the safety factor if stamped on the material is usually not published, 2) With only a country of origin (esp. China) stamped on the hardware, it is hard to trace liability, and what other reason? 451) For stage rigging on the subject of reserve strength of wire rope, how many wires can be broken on a lineset before it should be replaced? 452) Wire ropes with more strands have better fatigue resistance, but for the most part less strength, what is one other advantage cable with more strands? 453) When installing a new wire rope, it should be taken off the spool so that the major bending is in the same or opposite direction as it was on the spool? 454) By how much can installing wire rope in the wrong direction from the spool reduce the life of the wire rope? 455) What two things will increasing sheave tread diameters do for wire rope? 456) What two types of wire rope are permissible to use in hemp houses on hemp shives? Why? 457) What does 6x37 IWRC stand for? 458) What would be the advantage besides smaller bending radius, of using fiber core cable over solid or stranded core wire rope? 459) For what two reasons is galvanized wire rope the standard cable for the industry over stainless steel? 460) What are the differences between rotation resistant wire rope and sash cord wire ropes? 461) Which type of wire rope is weakest and strongest, Bright Sash, Tiller Rope, Plow Steel, or Galvanized Wire Rope? 462) On a trim chain with 1.1/2 wraps around the pipe, how do you attach the two ends of the chain to double the weight capacity of the trim chain? 463) Why should you not use regular steel chain on a fly system? 464) New trim chain comes with snap hooks/dog snaps, by current standards what is the purpose of it, and should you use a quick link, lap link, shackle, or grade 5 bolt to replace the snap hook? Why? 465) How do you tie a circus knot, and what is it used for? 466) On a batten, when a clove hitch is applied with wire rope clips above it, what is the efficiency of the attachment? 467) When using turnbuckles on a fly system what is required to be done to them to make them safe? 468) The proper sizing of a sheave to 7x19 aircraft cable D/d ratio is 4:1, 10:1, 25:1, or 50:1? 469) Wire guide arbors are used for fly systems with grid heights under how many feet? 470) Why are donut arbors frowned upon? 471) Spreader bars should be used every how many feet on a counterweight arbor? 472) What is the correct order to install 3 wire rope clips after a thimble? 473) What is the proper torque to apply to 1/8" wire rope clips and what size nut is it? 474) What is the proper order to install the crimps on a 1/8" nico sleeve and how many are required? 475) What is the reason not to re-use nuts to bolts for purposes of rigging? 476) What grade of bolt is used for most general purpose rigging applications? 477) Abrasion on wire rope is the result of rubbing, what is the name for when little cracks appear on wire rope and which is potentially more serious? 478) A wire broken under a tensile load that exceeds its strength is recognized by the “cup or cone configuration at the fracture point, coned break points indicate what? 479) The number of broken wires allowable on the running ropes in one rope lay for a tower or pillar crane is six, how many are allowable per strand? 480) A wire rope or electrical cable which has a tightly spiraling pig-tailed look when not under tension is the result of what? 481) Little knots or distortions and displacements in the grain of a wire rope but flush to it, is the result of what? 482) Big knots or distortions usually the wires from the inner core poking out of the wire rope are the result of what? 483) What is the minimum lifting angle to the center plane on a drop forged sholulder verses normal eyebolt? 484) Properly reeved splices in rope are considered to be how efficient? 485) What are two ways to ensure a screw pin shackle will not un-screw? What other types of shackle are available? 486) What should you do when two or more Spanset ends are to be installed on a chain hoist hook? 487) When two spansets with hooks or safety cables are installed bridle style on a beam with 2 rig points, which way should the opening of the hook face inboard or outboard? 488) What is the standard length of a new Schedule 40 pipe from a plumbing supplier? 489) What is the difference between the main and the grand drape? 490) What is an Olio and how is it different from show drops? 492) What is the difference between a show portal and a leg? 493) Where is the plaster line on stage? 494) What is the purpose of a Tab Drape? 495) What is a purchase line? 496) How are tableu or tabs rigged differently than pleated drapes? 497) To ensure fullness, how should you hang a drape? 498) When hanging drapes how many eyelets of over lap should there be between seems? 499) How are the on-stage ends of a leg tied off? 500) How do you go about bouncing the main? 501) When lowering a drop, electric, or other scenery on a fly system, where should your primary attention and eyes be directed? 502) How many lights can be pulled off an electric before it should be re-weighted? 503) 2-3%, 3-5%, 10-15%, or 20-25% is the maximum allowable voltage drop for a motor? 504) Load speed is appreciably below rated speed is caused from voltage drop or what? 505) Chain hoists should or should not be stored or transported at their pre-set limits, Why? 506) Why shouldn’t you operate or store a chain-hoist on its side? (2 reasons) 507) What is the maximum load rating of a Genie ST-24 Super Tower? 508) What is the standard batten weight including cable, gack, and standard instrument weight per fixture? 509) What is the difference in SWL between brass and aluminum Nicopress sleeves? 510) When rigging a sling in the choker, how is the shackle installed, and which has the highest SWL multiplier capacity, Wire rope, Fiber Webbing, or Chain? 511) Which is the proper formula for deadhang tension? (Length of member in tension) = L, (Vertical Length) = V, (Weight) = W, (Horizontal Distance) = H & (Tension) = T H2/V2 (W2) = T; H/V (W) = T; L/V (W) = T; D2/L (W) = T 512) What is the minimum safety factor for overhead lifting? 513) What is this a equation for? (Rigging Strength x Strength Reduction Factor) (Safety Factor x Load Increase Factor) 514) Federal and state occupational safety and health laws require that any employee in danger of falling more than 6' be protected from falling, so fall protection is required whenever people are on rigged equipment higher than this (stage hands on lighting trusses) for example. If their hoists are used to support people and the fall protection systems, what should the hoist load capacity be derated to? 1) Hoists already have a safety factor for this built into them, and do not have to be derated for intermittent use; 2) 75% Capacity; 3) 60% ; or 4) 50% 515) Static loading of any hoist should not exceed how much of its capacity? 516) Whenever a load is picked up, stopped, moved or swung, there is an increased force due to dynamic loading. The more rapidly or suddenly such actions occur, the greater this increase will be. In extreme cases, the force put on the rope may be two, three, or even more times the normal load involved. How is SWL of a rope designed to reflect this? 517) What agency is in charged with enforcing rigging safety? 518) When rigging, you choose the safety factor, calculate the allowable load than try to stay how much below it? 519) What is the SWL of ½” wire rope slings? 520) When using a shackle on a wire rope sling, besides SWLs matching up, what other factor should be considered in choosing a shackle to fit within the thimble opening? 521) When using a basket hitch, why is it necessary to use a shackle on one of the ends attached to the main shackle, and where on the shackle should it be installed, towards or away from the eyelet of the pin? 522) A basket hitch will hold how much weight above the SWL of the sling itself? 523) What is a split basket hitch and what is it used for? 524) What kind of a knot should you tie to equipment at the bottom of a drop line? 525) What is a pear ring used for? 526) When installing a roundsling on the pin of a shackle, what should you do to the sling to prevent the sling from twisting and un-screwing the pin? What would be a better way of hooking this connection up when possible? 527) How many shackles can be safely loaded on the hook to a chain hoist? 528) Why should you only hook two equal length bridles to each shackle? 529) How many layers of normal thickness burlap bag should be used to protect the corners of a beam? 530) When hooking up to a truss, why do you not hang from the top chords? 531) When hooking up to a truss, why do you have to wrap around junctions (panel points) and not points between panel points of the tubing? 532) When possible, why do you wrap slings around the parameter of a truss and not go through the center? 533) What is the minimum angle of a basket hitch tied around a truss to the pickup point shackle? 534) Why is a low head-room truss bracket OK for a truss layout with angles or boxes, but not Ok for a single span or length of truss? 535) What is the SWL and use of Stac Chains (Deck Chains) How many bends are they allowed? 536) Under current industry practice, Block and Falls with hooks are safe and usable 1) only with latches, with shackles, or either way? 537) What type of drop forged Eye-Bolt is the only type to be used for angular lifting? 538) What is the a strength loss to webbing & roundslings when wet, and what is the maximum operating temperature? 5% /130°; 10% /165°; 15% /180°; or 25% /210° 539) What is this the formula to? Force = (Weight) x [(Free Fall Distance/Stopping distance) +1] 540) If a rigging point fails, the dynamic load can be as much as ____ times the falling load, redundant points make up for this by carrying and distributing this load as much as possible under a safety factor of ____ when possible, for _____ times the original static load. (3 or 5; 10 or 12; 30 or 60) 541) Safeties for rigging should be (with a slight tension, or slightly slack)? 542) A 250# man wearing a safety harness with lanyard falls 6'. As he stops, the harness and lanyard stretch 6". What is the force on him and the rigging supporting him? If he has a shock absorber lanyard that extends 2' as it stops him, what will be the force? What if the shock absorber extends 42"? 543) Find the length of wire ropes, and the tension on them: (note: the load is evenly distributed) Two diagonal support cables have a horizontal distance from rig point to truss of 5' and a vertical distance of 10'. Truss weight or static load is 4,000 pounds. What is the SWL weight of the cable? Note: Diagonal Force = (Diagonal Length ÷ Vertical Length) x (Vertical Force) 544) If a center pickup point were installed vertically on this truss, what would the new figures be? 545) For dead hangs, try to keep the applied load at least 20 to 25% under the cable’s allowable load. If you do then: Dead hangs of ___ degrees off vertical are OK, without calculations needed. (Force increase of 15 degrees or less) Dead hangs between ___ and ___ degrees off vertical are possible, but must be calculated. Dead hangs more than ___ degrees off vertical should be avoided.Since most dead hangs are within ___ degrees of vertical, this rule given the safety factor and safety margin eliminates the need for most dead hang calculations given the SWL of the cable is known. 546) An electrician wants to lift a 600# dimmer board that is 8' long. He wraps it once around tightly with ½" manilla rope, ties a square knot, and puts a chain hoist hook on the rope at the center. The rope stretches 12", so there is some gap between the board and the hook. What is the tension on the rope? If wrapped around twice would it be any safer? A square knot is about 40-45% efficient. The bend on the box corner cuts the rope capacity to about 75% of its original strength. Given the above formula, and the rope’s tag rating of 2650#, is this safe? 547) What is this equation? Distance x Force = 2 feet x 50# = 100 ft-lbs. 548) What is the load distribution weight of a 1,000# truss 40' long when the first hoist is placed at one end and the second is placed 10' from the other end? 549) A 40' truss has an evenly distributed load of 800#, in addition to this, it has a 1,000# point load 10' from one end. What is the load on each lifting point if the first one is 10' from the end, the second one is in the center, and the third one is at the end of the truss? 550) What are the loads on the two pickup points of a 48' truss that weighs 1782#, and has a point load 10' from the second end of 1129#? [Load = (Span between Center of gravity or point load location and lifting point ÷ Total span) x (Weight)] 551) A weight on the end of a cantilever causes a load on the near support that is bigger than the weight itself. Lifting load at the closest point = distance between point load at the end of cantilever and the next closest support distance times the weight at the end of the cantilever. If rigging loads of a cantilever load are undesirable, what two things can be done to the first support to relieve this situation, given the first point closest to the load cannot change? Note: both answers involve a change in one part of the formula above and no ghost or phantom loads on the opposite end. 552) A beam has 4 supports, evenly spaced and with an even distribution of load. The total load is 2638# what is the load on each support using the intuition method and actual load method? 553) In what case would you use the intuition method for figuring load verses actual multi-point load distribution? Note: Intuitive multi-point load distribution assumes that on a straight level uniformly loaded beam supported at multiple evenly spaced points our intuition assumes that each support holds up half the weight of the beam sections hanging from it. Why is this different from how real load works? 554) The rule of thumb method assumes that with four or more points, the biggest difference on any point between intuition and good mathematics is 14% of section weight, defined as (X). This can be handled by making sure the rigging for each point can support 14% more than the intuition predicts, so assume all interior loads weigh 1.14X. With a three-point beam, the difference on the center point is 25%, so the center point rigging should support 25% more than intuition predicts it will weigh. End point loads are always under what intuition predicts, so don’t add anything to them beyond the intuitive answer. What is the rule of thumb load distribution for a evenly distributed load of 1,000# between 4 points with a point load of 200# three quarters of the way to support number three? 555) A 120' long truss is supported by 4 hoists evenly spaced every 40', numbered L1, L2, L3, and L4. The truss, lights, and cable together weigh 6,000#. The lights and cable are more-or-less evenly distributed, and the is a cable pick hoist that supports the weight of the multi-cable coming off the truss. There is also a point load of 1,000# 30' from L1. What are the loads on each hoist? 556) Truss supported by and raised and lowered by chain hoists pose certain problems when raising truss and other equipment, depending on their individual speeds amongst other things the weight of a truss can vary by how much at each support given a three motor truss? 557) How would a 20' x 20' square of truss differ in how loading was figured from a straight line 800' supported by the same number of hoists? 558) When using a four point bridle to support a box or square truss supported by the corners, you must design each corner to be able to support how much of the total weight? Why? 559) What is the difference in design loading for short term temporary rigging, with experts doing the rigging verses permanent installs with unknown personnel operating the equipment in the future? 560) The clutch on a chain hoist is designed to slip at approximately what percentage of its capacity? 561) Point loads at the center of an evenly supported truss with six points will approximately have how much added or subtracted weight on each member in reality due to the built-in flexibility of truss or pipe given the center will receive 70-80% of the actual point load? 562) How would a point load on a 7 point truss be given the load directly under the center load? 563) Why are trusses designed with flexibility or deflection in mind in relation to the flexibility of the buildings they are hung from? 564) If there is a cable drop off the end of a truss, it gets heavier as the truss rises and what? 565) An object hung on angled deadhangs rises more or the same as the length of the wire that runs into the hoist? On a 9 point suspension, of a box supported by two corners and the center on a vertical hang, and the rest diagonally what will be the solution to raising it? 566) Using the 3 to 1 rule, how much trim height can you get at a minimum on a 10' distance between beams to a point between them given a 12" truss and a 8" beam? What would be the span on the 90° rule. 567) On the 3 to 1 rule, a 1 foot change in the length of one leg makes how much of a change in the junction position? 568) The flatter the bridle angle the ___ the juxtaposition of the hanging point when moved. 569) What is this a formula for? (W = Weight, L = Diagonal Length, H = Horizontal Length, V = Vertical Length) Tension1 = W x L1 x H2 T2 = W x L2 x H1 V1 x H2 + V2 x H1 V1 x H2 + V2 x H1 Tension on the first leg decreases with length, as Tension increases on the second leg with length. 570) What is the full-load amperage of our ½ and 1 ton chain hoists?