Patent Publication Number: US-2021171321-A1

Title: Modular crane attachment device for purlins

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a crane attachment device and specifically to a crane attachment device that lifts a plurality purlins and sets the plurality of purlins onto the rafters of a steel building under construction. Modular crane attachment device for purlins lifts a plurality of purlins in one lift and sets the plurality of purlins in the exact position or close proximity required for immediate attachment to the rafters of a steel building under construction, which minimizes crane time, construction time, manpower, and safety hazards for the construction of a metal building. 
     2. Description of Related Art 
     This invention is used for the construction of a metal building and more specifically for the construction of a roof or roof framing on a metal building. A metal building roof or roof frame consists of a series of parallel rafters extending from one side of the building to the opposite side of the building. Attached to the rafters and at right angle to the rafters is a series of parallel purlins. A purlin is a horizontal beam along the length of a roof that is attached to one or more rafters. The roofing barrier or roofing sheet material is then attached on top of the purlins. 
     This invention is a device that is attached to a crane and set down near the supply stock of purlins on a construction site. Where a plurality of purlins is loaded onto this device that may include enough purlins to complete or fill in the entire width of the building. The device is then used to lift the plurality of purlins up to the rafters of a metal building under construction and, all at once, set each purlin in the exact location required for rigid attachment to the rafters. After all the purlins are attached to the rafters, the device is then set back down near the supply stock of purlins to repeat the cycle over and over again until all purlins are installed and set on the metal building. Prior to this invention, the standard way to attach purlins to the roof of a metal building was to lift and attach purlins on a one by one bases in between completed bays. With this invention, the entire bay may be filled with purlins with one crane lift rather than requiring several dozen crane lifts using the standard method. 
     There are many crane attachment devices in the prior art, however, there are none with the aspects as shown and described below. Modular crane attachment device for purlins is modular so that modules may be added or removed to yield the exact purlin carrying capacity that is required for any specific building size. Modular crane attachment device for purlins includes a plurality of adjustable J-hooks that are removeably attachable to any location along the length of the crane attachment device. Adjustable J-hooks are adjustable to receive and hold any size purlin. Modular crane attachment device for purlins is adjustable for pitch to accommodate the pitch of any roof of any metal building. Modular crane attachment device for purlins may be disassembled into a bundle of 10-20 foot long lengths of steel tubing that can be loaded onto a small truck or pickup truck. In best mode, modular crane attachment device for purlins may be quickly reassembled on the job site without requiring the use of any tools such as wrenches or screwdrivers. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an aspect of modular crane attachment device for purlins to attach to a hook or lift point of a crane. 
     It is an aspect of modular crane attachment device for purlins function with a crane that lifts heavy objects up and down on a construction site. 
     It is an aspect of modular crane attachment device for purlins to lift a plurality of purlins and place each purlin at the precise location on the rafters of a building to allow for immediate attachment of all purlins to the rafters wherein each purlin is fastened into place while held by the crane and modular crane attachment device for purlins which functions as an assembly jig in this manner. 
     It is an aspect of modular crane attachment device for purlins to lift a plurality of cross members and place each cross member at the precise location on the studs or wall of a building to allow for immediate attachment of all cross members to the studs or wall wherein each purlin is fastened into place while held by the crane and modular crane attachment device for purlins which functions as an assembly jig in this manner. 
     It is an aspect of modular crane attachment device for purlins to be modular where any number of modules may be assembled together to yield any length and any width in order to carry and lift any number and any length of purlins. 
     It is an aspect of modular crane attachment device for purlins to have a frame that includes a center section, a right section, and a left section. 
     It is an aspect of modular crane attachment device for purlins to include a hoist post that is pivotally attached to the frame of modular crane attachment device for purlins. 
     It is an aspect of modular crane attachment device for purlins to include a plurality of J-hooks that can be adjustably reversibly attachable to any position along the length of modular crane attachment device for purlins. 
     It is an aspect of modular crane attachment device for purlins to be modular so that the entire assembly may be broken down and dissembled into a bundle of 10-20 foot long structural members, fittings, and cables that can fit in any small truck or pickup truck. 
     It is an aspect of modular crane attachment device for purlins to be modular so that the entire assembly may be assembled from a bundle of 10-20 foot long structural members, fittings, and cables. 
     It is an aspect of best mode modular crane attachment device for purlins to be fully assembled from a bundle of 10-20 foot long structural members, fittings, and cables by hand and without any tools. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of modular crane attachment device for purlins. 
         FIG. 2A  is a front elevation view of modular crane attachment device for purlins. 
         FIG. 2B  is an enlarged view of hoist post cap, left lobe, and right lobe. 
         FIG. 3  is a rear elevation view of modular crane attachment device for purlins. 
         FIG. 4  is a left side elevation view of modular crane attachment device for purlins. 
         FIG. 5  is a right side elevation view of modular crane attachment device for purlins. 
         FIG. 6  is a top plan view of modular crane attachment device for purlins. 
         FIG. 7  is a bottom plan view of modular crane attachment device for purlins. 
         FIG. 8  is a perspective view of alternate modes of modular crane attachment device for purlins. 
         FIG. 9  is a front elevation view of alternate modes of modular crane attachment device for purlins. 
         FIG. 10  is a rear elevation view of alternate modes of modular crane attachment device for purlins. 
         FIG. 11  is a left side elevation view of alternate modes of modular crane attachment device for purlins. 
         FIG. 12  is a right side elevation view of alternate modes of modular crane attachment device for purlins. 
         FIG. 13  is a top plan view of alternate modes of modular crane attachment device for purlins. 
         FIG. 14  is a bottom plan view of alternate modes of modular crane attachment device for purlins. 
         FIG. 15  is an enlarged front elevation view of J-hook and vertical J-hook receiver. 
         FIG. 16  is an enlarged right side elevation view of J-hook and vertical J-hook receiver. 
         FIG. 17  is an enlarged front elevation view of J-hook and horizontal J-hook receiver. 
         FIG. 18  is an enlarged right side elevation view of J-hook and horizontal J-hook receiver. 
         FIG. 19  is bottom perspective view of modular crane attachment device for purlins showing environmental items including purlins, a crane, and metal building under construction. 
         FIG. 20  is a perspective view of an alternate mode of modular crane attachment device for purlins depicting a vertical lift using modular crane attachment device for purlins. 
     
    
    
     DEFINITION LIST 
       
     
       
         
           
               
               
             
               
                   
               
               
                 Term 
                 Definition 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                 5 
                 Modular Crane Attachment Device for Purlins 
               
               
                 10 
                 Hoist Post 
               
               
                 11 
                 Hoist Post Cap 
               
               
                 12 
                 Hoist Post Cap Lift Hole 
               
               
                 13 
                 Left Lobe 
               
               
                 14 
                 Left Lobe Hole 
               
               
                 15 
                 Right Lobe 
               
               
                 16 
                 Right Lobe Hole 
               
               
                 17 
                 Hoist Post Receiver 
               
               
                 18 
                 Upper Hub Plate 
               
               
                 19 
                 Lower Hub Plate 
               
               
                 20 
                 Center Section 
               
               
                 21 
                 Center Section Front Cross Member 
               
               
                 22 
                 Center Section Left Cross Member 
               
               
                 23 
                 Center Section Rear Cross Member 
               
               
                 24 
                 Center Section Right Cross Member 
               
               
                 25 
                 Center Section Front Spreader Bar 
               
               
                 26 
                 Center Section Rear Spreader Bar 
               
               
                 27 
                 Center Section Left End Member 
               
               
                 28 
                 Center Section Right End Member 
               
               
                 32 
                 T-Splice Fitting 
               
               
                 34 
                 Corner Splice Fitting 
               
               
                 36 
                 Pin 
               
               
                 40 
                 Right Section 
               
               
                 42 
                 Right Section Front Spreader 
               
               
                 44 
                 Right Section Rear Spreader 
               
               
                 46 
                 Right Section End Member 
               
               
                 48 
                 Additional Right Section 
               
               
                 50 
                 Left Section 
               
               
                 52 
                 Left Section Front Spreader 
               
               
                 54 
                 Left Section Rear Spreader 
               
               
                 56 
                 Left Section End Member 
               
               
                 58 
                 Additional Left Section 
               
               
                 60 
                 Right Front Cable 
               
               
                 62 
                 Left Front Cable 
               
               
                 64 
                 Right Rear Cable 
               
               
                 66 
                 Left Rear Cable 
               
               
                 68 
                 Cable for Vertical Application 
               
               
                 70 
                 J-Hook 
               
               
                 72 
                 Horizontal J-Hook Receiver 
               
               
                 74 
                 Vertical J-Hook Receiver 
               
               
                 100 
                 Metal Building Under Construction 
               
               
                 105 
                 Purlin or Purlins 
               
               
                 110 
                 Crane 
               
               
                 115 
                 Crane Hook or Lift Point 
               
               
                   
               
            
           
         
       
     
     DETAILED DESCRIPTION OF THE INVENTION 
     Modular crane attachment device for purlins  5  may be used for horizontal lifts or vertical lifts. A horizontal lift is the standard primary application wherein the modular crane attachment device for purlins  5  is held by the crane  110  in a generally horizontal orientation with an angle or pitch. Horizontal applications are depicted in in  FIGS. 1-14 and 17-19 . Horizontal lifts are used to attach purlins  105  to a roof or rafters. A vertical lift is an application wherein the modular crane attachment device for purlins  5  is held by the crane  110  in a vertical orientation. Modular crane attachment device for purlins  5  is depicted in  FIGS. 17, 18, and 20 . Vertical lifts are used to attach wall members or cross members to a wall or studs. 
     Modular crane attachment device for purlins  5  comprises: a center section  20 , a right section  40 , a left section  50 , a right front cable  60 , a left front cable  62 , a right rear cable  64 , and a left rear cable  66 . Modular crane attachment device for purlins  5  may further comprise one or more additional right sections  48  and/or one or more additional left sections  58 . 
     Center section  20  comprises: a hoist post  10 , a hoist post cap  11 , a left lobe  13 , a right lobe  15 , a hoist post receiver  17 , an upper hub plate  18 , a lower hub plate  19 , a center section front cross member  21 , a center section left cross member  22 , a center section rear cross member  23 , a center section right cross member  24 , a center section front spreader bar  25 , a center section rear spreader bar  26 , a center section left end member  27 , a center section right end member  28 , a left front T-splice fitting  32 , a left rear T-splice fitting  32 , a right front T-splice fitting  32 , and a right rear T-splice fitting  32 . 
     Hoist post  10  is a rigid oblong vertical member with an upper end, a lower end, a left surface, a right surface, a length, and a longitudinal axis. Hoist post  10  is a sturdy member that is capable of holding a large amount of weight without stretching, bending, or breaking. Hoist post  10  may be solid or made with tubular structure. Hoist post  10  has a length of about 10-30 feet. Hoist post  10  may be made of any known high strength material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, hoist post  10  is made of tubular steel. 
     Hoist post cap  11  is a specially designed and specially constructed article. Hoist post cap  11  is rigidly attached to the upper end of hoist post  10 . Hoist post cap  11  functions to provide an attachment point or lift point that is reversibly connectable to the hook or lift point  115  of a crane  110 . Hoist post cap  11  comprises: horizontal member, a vertical member, a left gusset member, and a right gusset member. Horizontal member is a rigid horizontal planar member with an upper surface, a lower surface, a perimeter, and a slot or groove. Slot or groove is a slot or linear opening through horizontal member that does not break out to the edge or perimeter of horizontal member. Vertical member is rigid vertical planar member with an upper end, a lower end, a left surface, a right surface, and a longitudinal axis. The lower end of vertical member is sized and shaped to make a slip fit or clearance fit into the slot or groove on horizontal member and vice versa. To assemble hoist post cap  11 , the lower end of vertical member is inserted through the slot or groove in the upper surface of horizontal member so that the lower end of vertical member protrudes through the lower surface of horizontal member and the horizontal member forms a right angle or ninety-degree angle with the vertical member wherein the longitudinal axes of hoist post  10  and vertical member are coincident. Then the protruded lower end of vertical member is rigidly attached to lower surface of horizontal member. Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by one continuous weld around the entire lower end of vertical member. The upper end of vertical member has a hoist post cap lift hole  12 . Hoist post cap lift hole  12  is a circular opening or hole in the upper end of vertical member. The hook or lift point  115  of a crane  110  is reversibly attachable to hoist post cap lift hole  12 . Hoist post cap lift hole  12  is located above left and right gusset members. Left gusset member is a rigid vertical right triangle shaped planar member with a long side, a short side, a hypotenuse, and a longitudinal axis. The long side of left gusset member is rigidly attached to the left surface of vertical member. The short side of left gusset member is rigidly attached to the upper surface of horizontal member. The ninety-degree angle of the right triangle member is nested within and contiguous with the ninety-degree angle between the horizontal member and the vertical member wherein the longitudinal axes of hoist post  10  and left gusset member are parallel, as depicted. Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by one continuous weld along the long and short sides of left gusset. Right gusset member is a rigid vertical right triangle shaped planar member with a long side, a short side, a hypotenuse, and a longitudinal axis. The long side of right gusset member is rigidly attached to the right surface of vertical member. The short side of right gusset member is rigidly attached to the upper surface of horizontal member. The ninety-degree angle of the right triangle member is nested within and contiguous with the ninety-degree angle between the horizontal member and the vertical member wherein the longitudinal axes of hoist post  10  and right gusset member are parallel, as depicted. Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by one continuous weld along the long and short sides of right gusset. Vertical member, horizontal member, left gusset member, and right gusset member may be made of from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, vertical member, horizontal member, left gusset member, and right gusset member are each made of steel sheet. 
     The hoist post cap  11  is rigidly attached to the upper end of hoist post  10 . The lower surface of horizontal member of hoist post cap  11  is rigidly attached to the upper end of hoist post  10 . Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by one continuous weld around the full perimeter of horizontal member. 
     Left lobe  13  is a rigid vertical planar member with an upper half, a lower half, a right edge, a left edge, a front surface, a rear surface, and a longitudinal axis. Left lobe  13  is rigidly attached to the left surface of hoist post  10  just below hoist post cap  11 , as depicted. Left lobe  13  functions to provide an attachment point for the left front cable  62  and the left rear cable  66  which function to help steady the load of purlins  105  during the lifting and setting of the load of purlins  105 . The right edge of left lobe  13  is rigidly attached to the left surface of hoist post  10  so that the longitudinal axes of hoist post  10  and left lobe  13  are parallel. Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by one continuous weld around the entire right edge of left lobe  13 . The lower half of left lobe  13  has a left lobe hole  14 . Left lobe hole  14  is a circular opening or hole in the lower end of left lobe  13 . 
     Right lobe  15  is a rigid vertical planar member with an upper half, a lower half, a right edge, a left edge, a front surface, a rear surface, and a longitudinal axis. Right lobe  15  is rigidly attached to the right surface of hoist post  10  just below hoist post cap  11 , as depicted. Right lobe  15  functions to provide an attachment point for the right front cable  60  and the right rear cable  64  which function to help steady the load of purlins  105  during the lifting and setting of the load of purlins  105 . The left edge of right lobe  15  is rigidly attached to the right surface of hoist post  10  so that the longitudinal axes of hoist post  10  and right lobe  15  are parallel. Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by one continuous weld around the entire left edge of right lobe  15 . The lower half of right lobe  15  has a right lobe hole  16 . Right lobe hole  16  is a circular opening or hole in the lower end of right lobe  15 . 
     Hoist post receiver  17  is a rigid vertical member with an upper end, a lower end, a front surface, a left surface, a rear surface, a right surface, and a longitudinal axis. The lower end of hoist post receiver  17  is rigidly attached to the upper surface of upper hub plate  18  so that its longitudinal axis is perpendicular to the horizontal axis of upper hub plate  18 . Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by welding: a gusset between to the front surface of the lower end of hoist post receiver  17  and the upper surface of upper hub plate  18 , a gusset between to the left surface of the lower end of hoist post receiver  17  and the upper surface of upper hub plate  18 , a gusset between to the rear surface of the lower end of hoist post receiver  17  and the upper surface of upper hub plate  18 , and a gusset between to the right surface of the lower end of hoist post receiver  17  and the upper surface of upper hub plate  18 . The upper end of hoist post receiver  17  is reversibly pivotally attachable to the lower end of hoist post  10 . Reversibly pivotal attachment may be accomplished by any known means. In best mode, reversible pivotal attachment is accomplished by a hinge member where the upper end of hoist post receiver  17  is a female hinge member with a horizontal hinge pin hole, the lower end of hoist post  10  is a male hinge member with a horizontal hinge pin hole, wherein the male hinge member is inserted into female hinge member to align their hinge pin holes where a heavy duty hinge pin is inserted therein to pivotally attach the lower end of hoist post  10  to the upper end of hoist post receiver  17 . Hoist post receiver  17  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, hoist post receiver  17  is made of tubular steel. Heavy duty hinge pin may be made of any known material such as: steel, metal, carbon fiber, composite, or any other known high strength material. 
     Upper hub plate  18  is a rigid planar member with an upper surface, a lower surface, a front end, a left end, a rear end, a right end, and a horizontal axis. The upper surface of upper hub plate  18  is rigidly attached to the lower end of hoist post receiver  17  as described above. Upper hub plate  18  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, upper hub plate  18  is made of steel sheet. 
     Lower hub plate  19  is a rigid planar member with an upper surface, a lower surface, a front end, a left end, a rear end, a right end, and a horizontal axis. Lower hub plate  19  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, lower hub plate  19  is made of steel sheet. 
     Center section front cross member  21  is a rigid oblong horizontal member with a front end, a rear end, an upper surface, a left surface, a lower surface, a right surface, a length, and a longitudinal axis. Length is about 2-10 feet. Center section front cross member  21  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section front cross member  21  is made of tubular steel. 
     Center section left cross member  22  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a rear surface, a lower surface, a front surface, a length, and a longitudinal axis. Length is about 2-15 feet. Center section left cross member  22  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section left cross member  22  is made of tubular steel. 
     Center section rear cross member  23  is a rigid oblong horizontal member with a front end, a rear end, an upper surface, a left surface, a lower surface, a right surface, a length, and a longitudinal axis. Length is about 2-10 feet. Center section rear cross member  23  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section rear cross member  23  is made of tubular steel. 
     Center section right cross member  24  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, a lower surface, a rear surface, a length, and a longitudinal axis. Length is about 2-15 feet. Center section right cross member  24  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section right cross member  24  is made of tubular steel. 
     Upper hub plate  18 , lower hub plate  19 , center section front cross member  21 , center section left cross member  22 , center section rear cross member  23 , and center section right cross member  24  are reversibly attached or assembled together to form the base frame or structural integrity of center section  20 . Upper hub plate  18 , lower hub plate  19 , center section front cross member  21 , center section left cross member  22 , center section rear cross member  23 , and center section right cross member  24  are assembled together as follows. 
     The upper surface of the rear end of center section front cross member  21  is reversibly attached to the lower surface of upper hub plate  18  at the front end. The lower surface of the rear end of center section front cross member  21  is reversibly attached to the upper surface of lower hub plate  19  at the front end. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of upper hub plate  18 , a vertical hole in the rear end of center section front cross member  21 , and a vertical hole in the front end of lower hub plate  19  to attach these members together. 
     The upper surface of the right end of center section left cross member  22  is reversibly attached to the lower surface of upper hub plate  18  at the left end. The lower surface of the right end of center section left cross member  22  is reversibly attached to the upper surface of lower hub plate  19  at the left end. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of upper hub plate  18 , a vertical hole in the right end of center section left cross member  22 , and a vertical hole in the left end of lower hub plate  19  to attach these members together. 
     The upper surface of the front end of center section rear cross member  23  is reversibly attached to the lower surface of upper hub plate  18  at the rear end. The lower surface of the front end of center section rear cross member  23  is reversibly attached to the upper surface of lower hub plate  19  at the rear end. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of upper hub plate  18 , a vertical hole in the front end of center section rear cross member  23 , and a vertical hole in the rear end of lower hub plate  19  to attach these members together. 
     The upper surface of the left end of center section right cross member  24  is reversibly attached to the lower surface of upper hub plate  18  at the right end. The lower surface of the left end of center section right cross member  24  is reversibly attached to the upper surface of lower hub plate  19  at the right end. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of upper hub plate  18 , a vertical hole in the left end of center section right cross member  24 , and a vertical hole in the rear end of lower hub plate  19  to attach these members together. 
     The longitudinal axes of the center section front cross member  21  and the center section rear cross member  23  are coincident. The longitudinal axes of the center section left cross member  22  and the center section right cross member  24  are coincident. The longitudinal axes of the center section front cross member  21  and the center section rear cross member  23  are perpendicular to the longitudinal axes of the center section left cross member  22  and the center section right cross member  24 , as depicted. The longitudinal axis of each cross member  21 , 22 , 23 , 24  is perpendicular to that of hoist post  10 . The four cross members  21 , 22 , 23 , 24  attached to upper and lower plates  18 , 19  form a rigid cross-shaped assembly or rigid plus sign shaped assembly as depicted. 
     Center section front spreader bar  25  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, a lower surface, a rear surface, a length, a mid-point, and a longitudinal axis. Length is about 5-20 feet. There is a plurality of horizontal holes in the front surface and the rear surface of center section front spreader bar  25  running uniformly along the entire length of the center section front spreader bar  25 . Center section front spreader bar  25  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section front spreader bar  25  is made of tubular steel. 
     Center section rear spreader bar  26  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, a lower surface, a rear surface, a length, a mid-point, and a longitudinal axis. Length is about 5-20 feet. There is a plurality of horizontal holes in the front surface and the rear surface of center section rear spreader bar  26  running uniformly along the entire length of the center section rear spreader bar  26 . Center section rear spreader bar  26  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section front spreader bar  25  is made of tubular steel. 
     Center section left end member  27  is a rigid oblong horizontal member with a front end, a rear end, an upper surface, a left surface, a lower surface, a right surface, a length, a mid-point, and a longitudinal axis. Length is about 8-30 feet. Center section left end member  27  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section left end member  27  is made of tubular steel. 
     Center section right end member  28  is a rigid oblong horizontal member with a front end, a rear end, an upper surface, a left surface, a lower surface, a right surface, a length, a mid-point, and a longitudinal axis. Length is about 8-30 feet. Center section right end member  28  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, center section right end member  28  is made of tubular steel. 
     Each T-splice fitting  32  is a female by female by female T-shaped socket fitting or pipe fitting. Each T-splice fitting  32  is a rigid member. Each T-splice fitting  32  has three female sockets that form a T shape. Each T-splice fitting  32  has a base socket, a left socket, and a right socket to form the T shape. Base socket is at the base of the T shape. Left and right sockets are at the top of the T shape. T-splice fitting  32  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, T-splice fitting  32  is made of tubular steel. 
     The left end of center section front spreader bar  25  slides into the left socket of the left front T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of center section front spreader bar  25  and a vertical hole the left socket of the left front T-splice fitting  32  to attach these members together. The right end of center section front spreader bar  25  slides into the right socket of the right front T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of center section front spreader bar  25  and a vertical hole the right socket of the right front T-splice fitting  32  to attach these members together. The front end of center section front cross member  21  is reversibly attachable to the rear surface of center section front spreader bar  25  at its midpoint. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by sliding the front end of center section front cross member  21  over a rigid male protrusion extending outward from the rear surface of center section front spreader bar  25  at its midpoint with one or more removable vertical pins that each extend through a vertical hole in the front end of center section front cross member  21  and a vertical hole in the rigid male protrusion to attach these members together. 
     The left end of center section rear spreader bar  26  slides into the right socket of the left rear T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of center section rear spreader bar  26  and a vertical hole the right socket of the left rear T-splice fitting  32  to attach these members together. The right end of center section rear spreader bar  26  slides into the left socket of the right rear T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of center section rear spreader bar  26  and a vertical hole the left socket of the right rear T-splice fitting  32  to attach these members together. The rear end of center section rear cross member  23  is reversibly attachable to the front surface of center section rear spreader bar  26  at its midpoint. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by sliding the rear end of center section rear cross member  23  over a rigid male protrusion extending outward from the front surface of center section rear spreader bar  26  at its midpoint with one or more removable vertical pins that each extend through a vertical hole in the rear end of center section rear cross member  23  and a vertical hole in the rigid male protrusion to attach these members together. 
     The front end of center section left end member  27  slides into the base socket of the left front T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of center section left end member  27  and a vertical hole the base socket of the left front T-splice fitting  32  to attach these members together. The rear end of center section left end member  27  slides into the base socket of the left rear T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of center section left end member  27  and a vertical hole the base socket of the left rear T-splice fitting  32  to attach these members together. The left end of center section left cross member  22  is reversibly attachable to the right surface of center section left end member  27  at its midpoint. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by sliding the left end of center section left cross member  22  over a rigid male protrusion extending outward from the right surface of center section left end member  27  at its midpoint with one or more removable vertical pins that each extend through a vertical hole in the left end of center section left cross member  22  and a vertical hole in the rigid male protrusion to attach these members together. 
     The front end of center section right end member  28  slides into the base socket of the right front T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of center section right end member  28  and a vertical hole the base socket of the right front T-splice fitting  32  to attach these members together. The rear end of center section right end member  28  slides into the base socket of the right rear T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of center section right end member  28  and a vertical hole the base socket of the right rear T-splice fitting  32  to attach these members together. The right end of center section right cross member  24  is reversibly attachable to the left surface of center section right end member  28  at its midpoint. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by sliding the right end of center section right cross member  24  over a rigid male protrusion extending outward from the left surface of center section right end member  28  at its midpoint with one or more removable vertical pins that each extend through a vertical hole in the right end of center section right cross member  24  and a vertical hole in the rigid male protrusion to attach these members together. 
     Right section  40  comprises: a right section front spreader bar  42 , a right section rear spreader bar  44 , a right section end member  46 , a front corner splice fitting  34 , and a rear corner splice fitting  34 . 
     Right section front spreader bar  42  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, a lower surface, a rear surface, a length, a mid-point, and a longitudinal axis. Length is about 5-20 feet. There is a plurality of horizontal holes in the front surface and the rear surface of right section front spreader bar  42  running uniformly along the entire length of the right section front spreader bar  42 . Right section front spreader bar  42  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, right section front spreader bar  42  is made of tubular steel. 
     Right section rear spreader bar  44  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, lower surface, a rear surface, a length, a mid-point, and a longitudinal axis. Length is about 5-20 feet. There is a plurality of horizontal holes in the front surface and the rear surface of right section rear spreader bar  44  running uniformly along the entire length of the right section rear spreader bar  44 . Right section rear spreader bar  44  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, right section front spreader bar  42  is made of tubular steel. 
     Right section end member  46  is a rigid oblong horizontal member with a front end, a rear end, an upper surface, a left surface, a lower surface, a right surface, a length, a mid-point, and a longitudinal axis. Length is about 8-30 feet. Right section end member  46  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, right section end member  46  is made of tubular steel. 
     Each corner splice fitting  34  is a female by female elbow or ninety-degree socket fitting or pipe fitting with an outer dimension and an inner dimension. Each corner splice fitting  34  is a rigid member. Each corner splice fitting  34  has two female sockets that form an L shape. Each corner splice fitting  34  has a first socket and a second socket to form the L shape. First and second sockets lie in a horizontal plane. Each corner splice fitting  34  has a corner lift plate rigidly attached thereto. Corner lift plate is a rigid vertical planar member with a large hole or void and a small hole or void in its center or interior section. The inner dimension of the large hole is slightly larger than the outer dimension of corner splice fitting  34 . To attach corner lift plate to corner splice fitting  34 , corner splice fitting  34  is inserted through the large hole so that the corner plate straddles the 90 degree section or corner section of corner splice fitting  34  wherein the corner lift plate protrudes vertically upwards from the horizontally positioned corner splice fitting  34  while at a 45-degree angle at the center of the elbow shape. In this position, corner plate is rigidly attached to corner splice fitting  34  by a full perimeter weld around the entire perimeter of large hole. The small hole on corner lift plate is located on the section of corner plate that protrudes vertically upwards from the horizontally positioned corner splice fitting  34 . There must be sufficient corner lift plate material left around this small hole to provide the small hole with great tensile strength. This small hole is a lift hole. Each corner splice fitting  34  has a lift hole. Lift holes are used to attach to the lower ends of cables  60 , 62 , 64 , 66  as described below. Corner splice fitting  34  and corner lift plate may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, corner splice fitting  34  is made of tubular steel and lift plate is made of steel sheet. 
     The left end of right section front spreader bar  42  slides into the left socket of the right front T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of right section front spreader bar  42  and a vertical hole the left socket of the right front T-splice fitting  32  to attach these members together. The right end of right section front spreader bar  42  slides into the first socket of the front corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of right section front spreader bar  42  and a vertical hole the first socket of the front corner splice fitting  34  to attach these members together. 
     The left end of right section rear spreader bar  44  slides into the right socket of the right rear T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of right section rear spreader bar  44  and a vertical hole the right socket of the right rear T-splice fitting  32  to attach these members together. The right end of right section rear spreader bar  44  slides into the first socket of the rear corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of right section rear spreader bar  44  and a vertical hole the first socket of the rear corner splice fitting  34  to attach these members together. 
     The front end of right section end member  46  slides into the second socket of the front corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of right section end member  46  and a vertical hole the second socket of the front corner splice fitting  34  to attach these members together. The rear end of right section end member  46  slides into the second socket of the rear corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of right section end member  46  and a vertical hole the second socket of the rear corner splice fitting  34  to attach these members together. 
     Modular crane attachment device for purlins  5  may further comprise one or more additional right sections  48 . One or more additional right sections  48  are located in between center section  20  and right section  40 . Additional right sections  48  use T-spice fittings  32  instead of corner splice fittings  34  on the end to provide room for the attachment of the right section  40  or additional right sections  48 . There is always one center section  20  and one right section  40 . Optionally, there may be a plurality of additional right sections  48  there between. Each additional right section  48  comprises: a right section front spreader bar  42 , a right section rear spreader bar  44 , a right section end member  46 , a front T-splice fitting  32 , and a rear T-splice fitting  32 . Additional right sections  48  are assembled as follows. 
     The left end of right section front spreader bar  42  slides into the left socket of the right front T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of right section front spreader bar  42  and a vertical hole the left socket of the right front T-splice fitting  32  to attach these members together. The right end of right section front spreader bar  42  slides into the right socket of the front T-splice fitting  32  on right section  40  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of right section front spreader bar  42  and a vertical hole the right socket of the front T-splice fitting  32  to attach these members together. 
     The left end of right section rear spreader bar  44  slides into the right socket of the right rear T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of right section rear spreader bar  44  and a vertical hole the right socket of the right rear T-splice fitting  32  to attach these members together. The right end of right section rear spreader bar  44  slides into the left socket of the rear T-splice fitting  32  on right section  40  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of right section rear spreader bar  44  and a vertical hole the left socket of the rear T-splice fitting  32  to attach these members together. 
     The front end of right section end member  46  slides into the base socket of the front T-splice fitting  32  on right section  40  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of right section end member  46  and a vertical hole the base socket of the front T-splice fitting  32  to attach these members together. The open left socket on front T-splice fitting  32  is used to attach the right section  40  or additional right sections  48  as described above. The rear end of right section end member  46  slides into the base socket of the rear T-splice fitting  32  on right section  40  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of right section end member  46  and a vertical hole the base socket of the rear T-splice fitting  32  to attach these members together. The open right socket on rear T-splice fitting  32  is used to attach the right section  40  or additional right sections  48  as described above. 
     Left section  50  comprises: a left section front spreader bar  52 , a left section rear spreader bar  54 , a left section end member  56 , a front corner splice fitting  34 , and a rear corner splice fitting  34 . 
     Left section front spreader bar  52  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, a lower surface, a rear surface, a length, a mid-point, and a longitudinal axis. Length is about 5-20 feet. There is a plurality of horizontal holes in the front surface and the rear surface of left section front spreader bar  52  running uniformly along the entire length of the left section front spreader bar  52 . Left section front spreader bar  52  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, left section front spreader bar  52  is made of tubular steel. 
     Left section rear spreader bar  54  is a rigid oblong horizontal member with a left end, a right end, an upper surface, a front surface, a lower surface, a rear surface, a length, a mid-point, and a longitudinal axis. Length is about 5-20 feet. There is a plurality of horizontal holes in the front surface and the rear surface of left section rear spreader bar  54  running uniformly along the entire length of the left section rear spreader bar  54 . Left section rear spreader bar  54  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, left section rear spreader bar  54  is made of tubular steel. 
     Left section end member  56  is a rigid oblong horizontal member with a front end, a rear end, an upper surface, a left surface, a lower surface, a right surface, a length, a mid-point, and a longitudinal axis. Length is about 8-30 feet. Left section end member  56  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, left section end member  56  is made of tubular steel. 
     Each corner splice fitting  34  is a female by female elbow or ninety-degree socket fitting or pipe fitting with an outer dimension and an inner dimension. Each corner splice fitting  34  is a rigid member. Each corner splice fitting  34  has two female sockets that form an L shape. Each corner splice fitting  34  has a first socket and a second socket to form the L shape. First and second sockets lie in a horizontal plane. Each corner splice fitting  34  has a corner lift plate rigidly attached thereto. Corner lift plate is a rigid vertical planar member with a large hole or void and a small hole or void in its center or interior section. The inner dimension of the large hole is slightly larger than the outer dimension of corner splice fitting  34 . To attach corner lift plate to corner splice fitting  34 , corner splice fitting  34  is inserted through the large hole so that the corner plate straddles the 90 degree section or corner section of corner splice fitting  34  wherein the corner lift plate protrudes vertically upwards from the horizontally positioned corner splice fitting  34  while at a 45-degree angle at the center of the elbow shape. In this position, corner plate is rigidly attached to corner splice fitting  34  by a full perimeter weld around the entire perimeter of large hole. The small hole on corner lift plate is located on the section of corner plate that protrudes vertically upwards from the horizontally positioned corner splice fitting  34 . There must be sufficient corner lift plate material left around this small hole to provide the small hole with great tensile strength. This small hole is a lift hole. Each corner splice fitting  34  has a lift hole. Lift holes are used to attach to the lower ends of cables  60 , 62 , 64 , 66  as described below. Corner splice fitting  34  and corner lift plate may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, corner splice fitting  34  is made of tubular steel and lift plate is made of steel sheet. 
     The right end of left section front spreader bar  52  slides into the right socket of the left front T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of left section front spreader bar  52  and a vertical hole the right socket of the left front T-splice fitting  32  to attach these members together. The left end of left section front spreader bar  52  slides into the first socket of the front corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of left section front spreader bar  52  and a vertical hole the first socket of the front corner splice fitting  34  to attach these members together. 
     The right end of left section rear spreader bar  54  slides into the left socket of the left rear T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of left section rear spreader bar  54  and a vertical hole the left socket of the left rear T-splice fitting  32  to attach these members together. The left end of left section rear spreader bar  54  slides into the first socket of the rear corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of left section rear spreader bar  54  and a vertical hole the first socket of the rear corner splice fitting  34  to attach these members together. 
     The front end of left section end member  56  slides into the second socket of the front corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of left section end member  56  and a vertical hole the second socket of the front corner splice fitting  34  to attach these members together. The rear end of left section end member  56  slides into the second socket of the rear corner splice fitting  34  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of left section end member  56  and a vertical hole the second socket of the rear corner splice fitting  34  to attach these members together. 
     Modular crane attachment device for purlins  5  may further comprise one or more additional left sections  58 . One or more additional left sections  58  are located in between center section  20  and left section  50 . Additional left sections  58  use T-spice fittings  32  instead of corner splice fittings  34  on the end to provide room for the attachment of the left section  50  or additional left sections  58 . There is always one center section  20  and one left section  50 . Optionally, there may be a plurality of additional left sections  58  there between. Each additional left section  58  comprises: a left section front spreader bar  52 , a left section rear spreader bar  54 , a left section end member  56 , a front T-splice fitting  32 , and a rear T-splice fitting  32 . Additional left sections  58  are assembled as follows. 
     The right end of left section front spreader bar  52  slides into the right socket of the left front T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the right end of left section front spreader bar  52  and a vertical hole the right socket of the front right T-splice fitting  32  to attach these members together. The left end of left section front spreader bar  52  slides into the left socket of the front T-splice fitting  32  on left section  50  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of left section front spreader bar  52  and a vertical hole the left socket of the front T-splice fitting  32  to attach these members together. 
     The right end of left section rear spreader bar  54  slides into the left socket of the left rear T-splice fitting  32  on center section  20  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of right section rear spreader bar  44  and a vertical hole the right socket of the left rear T-splice fitting  32  to attach these members together. The left end of left section rear spreader bar  54  slides into the right socket of the rear T-splice fitting  32  on left section  50  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the left end of left section rear spreader bar  54  and a vertical hole the right socket of the rear T-splice fitting  32  to attach these members together. 
     The front end of left section end member  56  slides into the base socket of the front T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the front end of left section end member  56  and a vertical hole the base socket of the front T-splice fitting  32  to attach these members together. The open right socket on front T-splice fitting  32  is used to attach the left section  50  or additional left sections  58  as described above. The rear end of left section end member  56  slides into the base socket of the rear T-splice fitting  32  and is reversibly attachable thereto. Reversible attachment may be accomplished by any know means such as: screws, bolts, fasteners, rivets, pins, clips, snaps. In best mode, reversible attachment is accomplished by one or more removable vertical pins that each extend through a vertical hole in the rear end of left section end member  56  and a vertical hole the base socket of the rear T-splice fitting  32  to attach these members together. The open left socket of rear T-splice fitting  32  is used to attach the left section  50  or additional left sections  58  as described above. 
     Right front cable  60 , left front cable  62 , right rear cable  64 , and left rear cable  66  are each a length of cable or thick rope of wire or nonmetallic fiber with an upper end and a lower end. The lower end of right front cable  60  is reversibly attachable to the lift hole on the front corner splice fitting  34  of right section  40 . The lower end of right rear cable  64  is reversibly attachable to the lift hole on the rear corner splice fitting  34  of right section  40 . The lower end of left front cable  62  is reversibly attachable to the lift hole on the front corner splice fitting  34  of left section  50 . The lower end of left rear cable  66  is reversibly attachable to the lift hole on the rear corner splice fitting  34  of left section  50 . The upper end of right front cable  60  is reversibly attachable to right lobe hole  16 . The upper end of right rear cable  64  is reversibly attachable to right lobe hole  16 . The upper end of left front cable  62  is reversibly attachable to left lobe hole  14 . The upper end of left rear cable  66  is reversibly attachable to left lobe hole  14 . Reversible attachment may be accomplished by any know means such as by hook, ring, clevis, shackle, or similar. The length of right front cable  60 , left front cable  62 , right rear cable  64 , and left rear cable  66  must be adjusted so that the cables are without slack and under tension when attached. Right front cable  60  and right rear cable  64  function to carry load or weight from the right section  40  as modular crane attachment device for purlins  5  is being used to lift a plurality of purlins in the air. Left front cable  62  and left rear cable  66  function to carry load or weight from the left section  50  as modular crane attachment device for purlins  5  is being used to lift a plurality of purlins in the air. Center section  20 , right section  40 , and left section  50  are assembled together to form an overall planar assembly as depicted. Since hoist post  10  is pivotally attached to hoist post receiver  17 , the overall planar assembly of center section  20 , right section  40 , and left section  50  may be tilted to any pitch or angle to match the pitch or angle of the roof of the building  100 . The length of right front cable  60 , left front cable  62 , right rear cable  64 , and left rear cable  66  may be adjusted to match this pitch or angle so that the desired pitch or angle may be maintained during the lift a plurality of purlins in the air. 
     Modular crane attachment device for purlins  5  further comprises: a plurality of J-hooks  70  and a plurality of horizontal J-hook receivers  72  or a plurality of vertical J-hook receivers  74 . Modular crane attachment device for purlins  5  uses either horizontal J-hook receivers  72  or vertical J-hook receivers  74  at any one time. Modular crane attachment device for purlins  5  utilizes horizontal J-hook receivers  72  to conduct horizontal lifts wherein the modular crane attachment device for purlins  5  is held by the crane  110  in a generally horizontal orientation. Modular crane attachment device for purlins  5  is depicted with horizontal J-hook receivers  72  in  FIGS. 1-14 and 17-19 . Horizontal lifts are used to attach purlins  105  to a roof. Modular crane attachment device for purlins  5  utilizes vertical J-hook receivers  74  to conduct vertical lifts wherein the modular crane attachment device for purlins  5  is held by the crane  110  in a generally vertical orientation. Modular crane attachment device for purlins  5  is depicted with vertical J-hook receivers  74  in  FIGS. 17,18 , and  20 . Vertical lifts are used to attach wall members or cross members to a wall. 
     Each J-hook  70  is a rigid J-shaped member, hook member, or hook shaped member. Each J-hook  70  comprises: a long vertical member, a horizontal member, and a short vertical member. Long vertical member is a rigid oblong vertical member with an upper end, a lower end, an outer dimension, a length, and a longitudinal axis. Long vertical member has a length of about 1-6 feet. Long vertical member has a plurality of holes spaced along its entire length. Long vertical member may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, long vertical member is made of tubular steel. Horizontal member is a rigid oblong horizontal member with a left end, a right end, a length, and a longitudinal axis. Horizontal member has a length of about 3-30 inches. Horizontal member may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, horizontal member is made of tubular steel. Short vertical member is a rigid oblong vertical member with an upper end, a lower end, a length, and a longitudinal axis. Short vertical member has a length of about 3-30 inches. Short vertical member may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, short vertical member is made of tubular steel. The lower end of long vertical member is rigidly attached to the right end of horizontal member. The left end of horizontal member is rigidly attached to the lower end of short vertical member. The longitudinal axes of long and short vertical members are parallel and perpendicular to the longitudinal axis of horizontal member to form the J-shape. Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by welding. 
     Each horizontal J-hook receiver  72  is a rigid oblong vertical member with an upper end, a lower end, a front surface, a left surface, a rear surface, a right surface, a length, and a longitudinal axis. Horizontal J-hook receiver  72  has a length of about 1-6 feet. Horizontal J-hook receiver  72  has a plurality of holes spaced along its entire length. There is a plurality of holes in the front surface and the rear surface of horizontal J-hook receiver  72 . The upper end of horizontal J-hook receiver  72  has two rigid tabs or ears with a hole in each tab or ear. The upper end of Horizontal J-hook receiver  72  is reversibly pivotally attachable to: center section front spreader bar  25 , center section rear spreader bar  26 , any right section front spreader bar  42 , any right section rear spreader bar  44 , any left section front spreader bar  52 , or any left section rear spreader bar  54 . Reversible pivotal attachment may be accomplished by any known means. In best mode, reversible pivotal attachment is accomplished by aligning the two holes in the upper end of Horizontal J-hook receiver  72  with two holes in: center section front spreader bar  25 , center section rear spreader bar  26 , any right section front spreader bar  42 , any right section rear spreader bar  44 , any left section front spreader bar  52 , or any left section rear spreader bar  54 , and then inserting a hinge pin or pin  36  through the four holes to create a pivotal attachment between these members that pivots about the hinge pin. This attachment is depicted in  FIGS. 17 and 18 . A horizontal J-hook receiver  72  may be pivotally attached to any position along the lengths of center section front spreader bar  25 , center section rear spreader bar  26 , any right section front spreader bar  42 , any right section rear spreader bar  44 , any left section front spreader bar  52 , or any left section rear spreader bar  54  because there is a plurality of holes along these members as described above. In this way, modular crane attachment device for purlins  5  may be customized to fit any size building  100  with any required purlin-to-purlin distance. The lower end of horizontal J-hook receiver  72  has an open-ended tubular shape. The lower end of horizontal J-hook receiver  72  has an inner dimension or overall inner dimension that is slightly larger than the outer dimension of the long vertical member of J-hook  70 . The lower end of Horizontal J-hook receiver  72  is reversibly attachable to the upper end of long vertical member of J-hook  70 . Reversibly attachment may be accomplished by any known means. In best mode, reversibly attachment is accomplished by inserting the upper end of long vertical member of J-hook  70  into the open end of the lower end of horizontal J-hook receiver  72  to align a hole on long vertical member of J-hook  70  with two holes in horizontal J-hook receiver  72 , one hole on its front surface and one hole on its rear surface, and then inserting a hinge pin or pin  36  through the holes to attach these members, as depicted in  FIGS. 17 and 18 . A J-hook  70  may be attached to horizontal J-hook receiver  72  at multiple locations or multiple lengths because there is a plurality of holes along the length of the long vertical member of J-hook  70  where any one could be used to align with a plurality of holes along the length of horizontal J-hook receiver  72  for attachment thereto. Horizontal J-hook receiver  72  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, horizontal J-hook receiver  72  is made of tubular steel. 
     In order to use modular crane attachment device for purlins  5  to conduct standard horizontal lifts and to raise a plurality of purlins, the modular crane attachment device for purlins  5  is assembled as described above, wherein the required amount of left and right sections  40 , 48 , 50 , 58  is used to allow for the attachment of the desired amount of J-hooks  70  to attach the desired amount of purlins  105  to building  100 . The crane hook  115  is attached to hoist post cap lift hole  12  and modular crane attachment device for purlins  5  is lifted off the ground and held in a horizontal position near the purlin supply pile on the job site. The desired amount of J-hooks  70  is then attached to spreader bars  25 , 26 , 42 , 44 , 52 , 54  using a horizontal J-hook receiver for each J-hook  70 . Typically, two J-hooks  70  are required to lift one purlin  105 . The J-hooks must be position exactly as required to mate with the particular rafters or roof of building  100 . The desired amount of purlins  105  is then loaded onto the J-hooks  70  by placing the purlin  105  in the cradle section of the J-shape. The load of purlins is then raised up to the building  100  by the crane  110  and placed into the exact position or close proximity required for immediate attachment to the roof or rafters. Workers then attach all rafters. The modular crane attachment device for purlins  5  may be lowered to lift each purlin out of the cradle section of the J-hook  70  after placement to allow clearance. The empty modular crane attachment device for purlins  5  is then lifted away from the roof and lowered back to the purlin supply pile where the process is repeated until all purlins are attached to the roof or rafters. 
     Each vertical J-hook receiver  74  is a rigid elbow shaped vertical member with an upper end, a lower end, a front surface, a left surface, a rear surface, a right surface, a length, and a longitudinal axis. Vertical J-hook receiver  74  has a length of about 1-6 feet. Vertical J-hook receiver  74  has a plurality of holes spaced along its entire length. There is a plurality of holes in the front surface and the rear surface of vertical J-hook receiver  74 . The upper end of vertical i-hook receiver  74  has two rigid parallel tabs or ears that break from the longitudinal axis to form a bend or elbow shape as depicted. The two rigid tabs or ears are askew with the lower end. In best mode, the tabs or ears form a 135-degree angle with the lower end. There is a hole in each tab or ear. The upper end of vertical J-hook receiver  74  is reversibly attachable to: center section front spreader bar  25 , center section rear spreader bar  26 , any right section front spreader bar  42 , any right section rear spreader bar  44 , any left section front spreader bar  52 , or any left section rear spreader bar  54 . Reversible attachment may be accomplished by any known means. In best mode, reversible attachment is accomplished by aligning the two holes in the upper end of vertical J-hook receiver  74  with two holes in: center section front spreader bar  25 , center section rear spreader bar  26 , any right section front spreader bar  42 , any right section rear spreader bar  44 , any left section front spreader bar  52 , or any left section rear spreader bar  54 , and then inserting a hinge pin or pin  36  through the four holes to create an attachment between these members, as depicted in  FIGS. 15 and 16 . A vertical J-hook receiver  74  may be attached to any position along the lengths of center section front spreader bar  25 , center section rear spreader bar  26 , any right section front spreader bar  42 , any right section rear spreader bar  44 , any left section front spreader bar  52 , or any left section rear spreader bar  54  because there is a plurality of holes along these members as described above. In this way, modular crane attachment device for purlins  5  may be customized to fit any size building  100  with any required cross member to cross member distance. The lower end of vertical J-hook receiver  74  has an open-ended tubular shape. The lower end of vertical J-hook receiver  74  has an inner dimension or overall inner dimension that is slightly larger than the outer dimension of the long vertical member of J-hook  70 . The lower end of vertical J-hook receiver  74  is reversibly attachable to the upper end of long vertical member of J-hook  70 . Reversibly attachment may be accomplished by any known means. In best mode, reversibly attachment is accomplished by inserting the upper end of long vertical member of J-hook  70  into the open end of the lower end of vertical J-hook receiver  74  to align a hole on long vertical member of J-hook  70  with two holes in vertical J-hook receiver  74 , one hole on its front surface and one hole on its rear surface, and then inserting a hinge pin or pin  36  through the holes to attach these members, as depicted in  FIGS. 15 and 16 . A J-hook  70  may be attached to vertical J-hook receiver  74  at multiple locations or different lengths because there is a plurality of holes along the length of the long vertical member of J-hook  70  where any one could be used to align with a plurality of holes along the length of Vertical J-hook receiver  74  for attachment thereto. Vertical J-hook receiver  74  may be made from any known rigid material such as: steel, metal, carbon fiber, composite, or any other known high strength material. In best mode, vertical J-hook receiver  74  is made of tubular steel. 
     In order to conduct a vertical lift, two or more corner splice fittings  34  must each further comprise a vertical lift tab. Each vertical lift tab is rigid planar member rigidly attached to the exterior surface of a corner splice fitting  34 . Rigid attachment may be accomplished by any known means such as: weld, glue, epoxy, adhesive, bolts, screws, rivets, clips, or snaps. In best mode, rigid attachment is accomplished by welding. Each vertical lift tab has a vertical lift tab hole. Two vertical lift tabs are required to use modular crane attachment device for purlins  5  for a vertical lift. With vertical lifts, just two cables are used to attach modular crane attachment device for purlins  5  to crane hook  115 . In contrast, with horizontal lifts, all four cables  60 , 62 , 64 , 66  are used to attach modular crane attachment device for purlins  5  to crane hook  115 . With vertical lifts, the lower end of left front cable  62  is reversibly attached to a vertical lift hole on a vertical lift tab on left front corner splice fitting  34  and the left rear cable  66  is reversibly attached to a vertical lift hole on a vertical lift tab on left rear corner splice fitting  34 . Alternately, a vertical lift may be conducted with the lower end of right front cable  60  is reversibly attached to a vertical lift hole on a vertical lift tab on right front corner splice fitting  34  and the right rear cable  64  is reversibly attached to a vertical lift hole on a vertical lift tab on right rear corner splice fitting  34 . A vertical lift is depicted in  FIG. 20 .