US3876073A

US3876073A - Heavy duty paper board reel

Info

Publication number: US3876073A
Application number: US329244A
Authority: US
Inventors: Stephen A Herbetko
Original assignee: Connelly Containers Inc
Current assignee: Connelly Containers Inc
Priority date: 1973-02-02
Filing date: 1973-02-02
Publication date: 1975-04-08
Anticipated expiration: 1992-04-08

Abstract

A reel for heavy duty use is provided, made entirely of corrugated paper board. The reel comprises a pair of flange plates and an axially extending core. The flange plates are preferably formed of two sub-plates secured together, each subplate comprising multi-layer corrugated board, with the corrugations of the two sub-plates being transverse. The core is secured to the flange plates by locking fingers, the core being formed of a circumferential series of panels, alternate panels having a locking finger at each end thereof. The locking fingers have a flap and a locking tab, the fingers and tabs extending through slots in the flange plate. In one embodiment a reinforcing structure is provided within the core, with at least one locking tab at each end engaging the reinforcing structure to interlock it with the core and flange plates. A locking tab and slot construction is provided on the core to secure it into a generally cylindrical formation. Cable, hose or other linear material coiled on the reel is covered with a peripheral paper board sheet, which is secured in position. The reel components may be impregnated with a wax material to impart additional strength.

Description

United States Patent [191 Herbetko 1 HEAVY DUTY PAPER BOARD REEL [75] Inventor: Stephen A. l-lerbetko, Philadelphia.

[73] Assignee: Connelly Containers, lnc., Bala Cynwyd. Pa.

[22] Filed: Feb. 2, 1973 [21] Appl. No.: 329.244

[52] U.S. Cl. 206/400; 242/155; 242/118.8 [51] Int. Cl 865d 85/04; B65h 75/14 [58] Field of Search 242/1 18.8, 118.7. 118.4, 2421115, 118.6, 118.61, 159, 170; 206/52 R, 460, 398

[56] References Cited UNITED STATES PATENTS 335.692 2/1886 Fries 242/1 18.8 1.052.303 2/1913 Aven 242/1 18.8 2.799.458 7/1957 Nye 242/118.8 2,853,185 9/1958 Rollie.... 206/52 R 1059,7615 10/1962 Eifrid............ 242/1 18.8 3,412,847 1 [/1968 Wise et 242/1 18.8 X 3.537.667 11/1970 Dorman 242/1 18.8 FOREIGN PATENTS OR APPLICATIONS 1.018.914 2/1966 United Kingdom 242/170 706.260 3/1965 Canada 242/1 18.8

1.243.063 8/1971 United Kingdom 24211187 51 Apr. 8, 1975 Primary Examiner-George F. Mautz Attorney, Agent. or F irmlrvin A. Lavine [57] ABSTRACT A reel for heavy duty use is provided. made entirely of corrugated paper board. The reel comprises a pair of flange plates and an axially extending core. The flange plates are preferably formed of two sub-plates secured together. each sub-plate comprising multi-layer corrugated board, with the corrugations of the two subplates being transverse. The core is secured to the flange plates by locking fingers, the core being formed of a circumferential series of panels, alternate panels having a locking finger at each end thereof. The locking fingers have a flap and a locking tab, the fingers and tabs extending through slots in the flange plate. in one embodiment a reinforcing structure is provided within the core. with at least one locking tab at each end engaging the reinforcing structure to interlock it with the core and flange plates. A locking tab and slot construction is provided on the core to secure it into a generally cylindrical formation. Cable, hose or other linear material coiled on the reel is covered with a pe ripheral paper board sheet, which is secured in posi tion. The reel components may be impregnated with a wax material to impart additional strength.

8 Claims, 9 Drawing Figures HEAVY DUTY PAPER BOARD REEL BACKGROUND OF THE INVENTION The present invention pertains to a reel for storing and dispensing linearly extending material coiled thereon.

Reels have been used for many years for storing, shipping and dispensing linearly extending material which is coiled thereon. These reels have been used for relatively light weight materials, such as thread, paper or cloth in tape or sheet form, and light twine and cord. Such reels were often made of light weight metal, card board and the familiar wooden spool for holding sewing thread. Where heavy loads such as wire, electric cable, tubing and the like have been stored on reels, it has been conventional to utilize heavy wooden reels. Such heavy wooden reels or even composite wooden and metal reels, have been expensive to manufacture. could not be shipped in knocked-down condition. or if so shipped, required extensive labor at the users plant in order to erect them and were themselves substantially heavy, thereby contributing to the load on the workman and the moving equipment in connection with such reels.

In addition to the above conventional reels, the prior art contains a number of suggestions for utilizing reels made of paper material, such as corrugated paper board. For example, in one instance there was suggested a reel for carrying telephone cable comprised of a core of tubular construction made by wrapping long strips of paper around a spindle, this core thereby forming a cylinder with an axially extending hole, the cylinder having a solid paper wall of substantial thickness. End flanges were secured to this cylindrical core by being glued to the end faces of the core, these end flanges comprising a composite structure of corrugated paper board and a layer of a second material, such as pressed fiber board or thin ply wood. This construction could not be shipped flat and assembled by the user, required a relatively heavy weight core, and was not made entirely of paper board material.

Another construction known in the prior art was of a spool or reel made of solid fibre board, corrugated fibre board, or other suitable material, and included a pair of end panels and a hub-forming member made of a body blank comprising a plurality of side wall panels defined by side scores, the side wall panels having tapered positioning flaps and a holding tab extending from the ends thereof. A strip of adhesive tape was used to join the ends ofthe body blanks together. While this construction could be shipped in flat condition, it was intended, apparently, for relatively light weight use such as wire, tape, and strap.

Yet another construction known in the prior art was intended for receiving and paying out relatively light weight filament-like products, which was fabricated of card board, corrugated board and other relatively light weight materials. This reel provided a core formed of a cut and scored blank, the blank including panels separated from one another by score lines, the panels having at their ends hooks which serve to interconnect the core with the side walls of the reels, the hooks also functioning to partially define the bearing surfaces of the reel for an axle which supports the reel. This construction, being intended for light weight materials, was not sufficiently strong to enable it to be used for relatively heavy materials.

Other suggestions in the prior art include reels with some reinforcement in the core, such as a paper reel with a steel wire frame. While such reels might be relatively strong, they were also somewhat costly. since they were not made entirely of paper board, and obviously could not be shipped in flattened condition.

Among the objects of the present invention are to provide a reel for supporting heavy loads, and thereby capable of heavy duty usage, such reels being of light weight and high strength.

Another object of the present invention is to provide a heavy duty, heavy load reel constructed substantially entirely of light weight paper board material.

Yet another object of the present invention is the provision of a heavy duty reel made of paper board, which can be shipped in flattened condition, and another object of the present invention is to provide such a reel which can be easily erected by the user without machinery or equipment such as metal stitching devices or machines.

Yet another object of the present invention is to provide a reel construction which will support heavy loads, and which, while being made entirely of paper board, will not deteriorate under adverse weather conditions.

Still another object of the present invention is the provision of a reel construction in which the material stored on the reel is protected against damage, as by abrasion or weather.

Other objects and many of the attendant advantages of the present invention will be readily understood from the following specification and drawings.

SUMMARY OF THE INVENTION The present invention provides a heavy duty reel of paper board material. the reel comprising a core and a pair of flange plates. The flange plates are formed of two sub-plates secured together, as by adhesive, and each sub-plate comprises multi-layer corrugated board, having for example two or three corrugated paper me diums. The corrugations of one sub-plate are perpendicular to the corrugations of the other sub-plate. The core is formed of a circumferential series of panels, with alternate panels having locking fingers at each end. Each locking finger extends through a slot in a flange plate, an integral flap extends from the locking finger along the outside of the flange plate, radially inwardly, and at its end has a locking tab which extends through another slot in the end flange, the locking tab having a slightly wider extent than the slot, to provide for secure holding action. For protection against the elements, and for added strength, these three components may be impregnated with a resinous material, such as wax. For the heaviest duty, to sustain the heaviest loads, a reinforcing structure is provided within the hollow core, the reinforcing structure receiving at least one locking tab of the core, to thereby provide for interengagement and structural interaction of the core, reinforcement and flange plates. The reinforcement preferably comprises a pair of generally U-shaped members, each U-shaped member comprising a pair of spaced parallel legs connected by a panel, the legs being provided with slits and the legs of one member entering into the legs of the other member, by means of the slits. Thus, the panels of the U-shaped members are positioned so that they are in substantial engagement with the inner sides of the end flanges, and the legs have edges which are in substantial engagement with the interior ofthe core. Hence, the reinforcement serves to add column strength to the reel when a plurality of reels are stacked on their end flanges, and also adds beam strength to the core to prevent its yielding under the load of the material carried on the core. In final form, the material, such as heavy cable, which is coiled on the reel may be protected by a circumferential sheet of heavy paper board material secured in position by conventional means, such as metal strapping.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a reel in accordance with the present invention.

FIG. 2 is an exploded view, in perspective, of subplates forming the flange plates of the reel of FIG. 1.

FIG. 3 is a plan view ofthe core blank for forming the core of the reel of FIG. 1.

FIG. 4 is a perspective view with parts broken away taken interiorally of the core, showing the locking tab construction.

FIG. 5 is a perspective view, with parts broken away showing the core and end flange interlock.

FIG. 6 is an exploded perspective view, with parts broken away. of the reinforcing structure which may be used with the reel of FIG. I.

FIG. 7 is an exploded perspective view, with parts broken away, showing the reel with the reinforcing structure in the core.

FIG. 8 is a cross sectional view taken on the line 88 of FIG. 7.

FIG. 9 is a perspective view, with parts broken away, of a reel and a protective covering.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, wherein like or corre sponding reference numerals are used to designate like or corresponding parts throughout the several views. there is shown in FIG. 1 a reel generally designated 10, which is made substantially entirely of paper board. Reel 10 comprises a generally longitudinally extending core 11 and a pair of flange plate 30, which are preferably of circular configuration. The flange plates 30 are of substantially identical construction, which is disclosed specifically, in preferred form, in FIG. 2.

Referring to FIG. 2, each flange plate 30 may be seen to comprise a sub-plate 31 and a second sub plate 32, which are of substantially identical construction, subplate 31, for example, comprises a multilayer corrugated board. Thus, the sub-plate 31 has a pair of corrugated medium sheets 33 interposed between and adhesively secured to three flat paper liner sheets 34. As in dicated by the arrows, the corrugations ofthe sub-plate 31 are parallel to each other, and the corrugations of the sub-plate 32 are parallel to each other, the corrugations of sub-plate 31 being transverse to, preferably perpendicular, the corrugations of the sub-plate 32, as also indicated by the arrows of FIG. 2. These two

subplates

31 and 32 are secured together, with the corrugations transverse, preferably perpendicular, as indicated, so as to obtain maximum strength. The securement of the sub-plates is preferably by a suitable adhesive.

The sub-plates 31 and 32 are provided with an outer annular series of slots 36 and an inner annular series of slots 37, for purposes to be hereinafter described, the

slots being in alignment when the sub-plates 31 and 32 are assembled as above described.

Referring now to FIG. 3, there is shown the blank for forming the core 11, comprising a first group of alternate panels 12, 12A12G and a second group of

alternate panels

13, 13A-13G, the panels of the first group being interposed between the panels of the second group. The panels of the

second group

13, 13A are somewhat shorter than the panels of the

first group

12, 12A, so that each of the panels 12 has at its opposite ends a length or extension generally designated 12' and 12". These extensions 12' and 12" constitute locking fingers, and are each substantially of a length equal to the thickness of a flange plate 30, being defined by a score line 14 which separates the locking finger 12', 12" from an integral flap 16. Each flap 16 is tapered outwardly, and is separated by a score line 17 from a locking tab 18 which is of narrowest extent at the score line 17 and comprises an outer rounded head 19 with inwardly facing shoulder 19'. As will be understood, there are as many locking fingers 12', 12", flaps 16 and locking tabs 18 as there are pairs of

slots

36, 37 in the flange plates 30. Further, the core 11 is provided with a structure for securing axially extending edges thereof, without requiring additional metal stitching, tape or the like.

Specifically, the blank of the core 11 as shown in FIGv 3 includes adjacent the panel 12 and extending in tegrally therefrom a locking tab 21, which preferably lies along a central median plane of the blank of the core 11, locking tab 21 having a pair of flaps 22 extending therefrom, generally parallel to but separated from the panel 12, the flaps 22 being hingedly connected to the locking tab 21 and separated from it by a score line 23. Adjacent the panel there is a panel 24 which is of substantially the same size as the panel 130, separated from it by a score line 26: in the panel 24 and adjacent the score line 26 is a slot 27 which has a width along the median line of the blank shown in FIG. 3 which is approximately equal to three times the thickness of the corrugated board of which the blank is made, and having a length transverse to the medium line which is at least as long as the length of the locking tab 21 between the score lines 23.

Referring now to FIG. 4, there is shown a first step in the erection of a reel 10, this being the formation median the blank shown in FIG. 3 into a generally cylindrical configuration. Thus, there is shown the panel 24 which lies inwardly of the panel 12, which is not shown, although the locking fingers l2 and 12" may be seen.

Adjacent panels

13 and 12A may be seen, as well as the end panel 136 and the adjacent panel 12G. The locking tab 21 is seen extending through the slot 27, the flaps 22 having been folded into overlying rela tionship to the locking tab 21 and the locking tab 21 and flaps 22 then being pushed through the slot 27, after which the flaps 22 were moved or caused to be moved to the locking positions as shown in FIG. 4, preventing withdrawal of the locking tab structure including the flaps 22 through the slots 27.

Referring now to FIG. 5, there may be seen the reel 10 including a part of the core 11, specifically including the

panels

12A,13A, 12B, 13B. Panel 12A may be seen to have

integral locking fingers

12A and 12A" extending through slots 36 in the flange plates 30. There may also be seen the flaps 16 which extend along the outer surface of the flange plates 30, towards the slots 37 of the inner annular series of slots, and the locking tabs 18 at either end which extend through the slots 37, and which are somewhat wider than the slots 37in order to provide for security of engagement and prevent accidental withdrawal of the locking tabs 18 through the slots 37', the ends of the

panels

13, 13A-l3G engage the inside surfaces of the flange plates 30.

Reel as hereinabove described may be manufactured substantially entirely of corrugated paper board. as indicated, and in addition, may be shipped in flattened condition, to thereby conserve shipping and storage space. in addition, in some instances the core 11 and flange plates 30 may be impregnated with a suitable resinous or wax material. which will thereby substantiaily increase the strength of the reel. Where conventional resinous material or wax is utilized, the corrugated board material is so stiff that erection by the user is not possible, since the flaps cannot be manipulated, and so the reel is first assembled, and is then impregnated with the high strength resinous or wax material, and is then shipped in erected condition. This material also provides protection against weakening of the reel 10 from moisture, such as rain or snow.

Referring now to FIG. 6, there is shown a reinforcing structure generally designated 40, and comprising a pair of substantially identical U-shaped members 41 made of corrugated paper board. Each member 41 comprises a pair of spaced

parallel legs

42 and 43 with a back panel 44 integral with them, and extending between them, preferably at right angles to them. Leg 42 is provided with a pair of

slits

42A and 42B and leg 43 is provided with a pair of

corresponding slits

43A and 42B and leg 43 is provided with a pair of corresponding slits 43A and 438, the slits extending from the free ends of the legs inwardly toward the panel 44, and thereby define fingers. The back panels 44 are provided with a pair of slots 46, and also, preferably, with a central circular opening 47.

Referring now to FIG, 7, there may be seen a reel 10 in perspective view, partially assembled. Thus, there is provided a flange plate 30 to which the core 1] has been assembled by passing the locking fingers through the slots 36 and the locking tabs through the slots 37. As will be understood, the formation ofthe core ll into generally cylindrical configuration will have previously taken place, in the manner illustrated in connection with FIG, 4. One of the U-shaped members 41 of the reinforcing structure 40 will have been placed on a surface of the flange plate 30 with the back panel 44 thereof in engagement therewith, and with the slots 46 in the back panel 44 passed over a pair of the locking tabs 18. Either prior to or subsequent to this assembly operation, the fingers formed by the slits in the

legs

42 and 43 of the U-shapcd members 4] will have been interdigitated, the

legs

42 and 43 of one U-sl'iaped member 41 extending towards the back panel of the other U-shaped member 41. The resulting reinforcing structure 40 will have an axial extent, along the axis of the core 11, of the same amount as the length of the panels 13, l3A-l3G. Consequently, when the second flange plate 30 is assembled, the locking fingers, flaps and locking tabs will be passed through the slots 36 until the inner or underneath surface of the flange plate 30 engages the ends of the panels 13, l3A-l3G and the panel 44 of the U-shaped reinforcing member 41 adjacent thereto. Then the flaps 16 are bent, as shown in FIG. 8, and the locking tabs 18 are forced through the slots 37 in the flange plate 30, the locking tab 18 also passing through a slot 46 in the back panel 44. Consequently, the reel 10 has substantial additional strength in the axial direction, and is thereby able to be stacked, so that a plurality of reels loaded with heavy wire or insulated cable, may be placed one on top of the other, without danger of collapsing the bottom-most reel which carries the greatest weight. This is due to the fact that the back panels 44 of each of the U-shaped reinforcing members 41 engages with the inner surface of the adjoining flange 30, and thereby contribute to the column strength of the reel 10 when placed on its side, in addition to the column strength obtained through the use of the core 11.

It will further be understood that the length of the panels 44 is such that they extend between the inner surfaces of the core 11, engaging these inner surfaces and thereby adding to the strength of the core ll, when it functions as a beam, as when the reel 10 is resting on the flange plates 30. Consequently, the core 11 is reinforced against bending in this position, as well as against columnar collapse when in the above noted po sition in which the reel lies on one or the other of the flange plates 30.

it will be noted in FIG. 8 that the opening 47 is in registry with a central opening 38 in the flange plate 30, to enable an axle or spindle to be passed through the reel, for supporting it, or possibly for driving it.

In use, the present invention corrugated paper board heavy duty reel has been found to be of extremely satisfactory cost and construction, enabling the carrying of relatively heavy loads of material. For example a reel in accordance with the present invention construction has flange plates of 44 inches in diameter and a core having an axial length of 30 inches; such a reel has sat isfactorily supported and stored, and been used in the shipment of material weighing some 400 pounds.

Referring now to FIG. 9, there may be seen a reel 10 including the flange plates 30, with reinforcing 40 within the core thereof. On the core there is coiled linearly extending material M, such as hose of rubber or plastic, cable, and the like, and overlying the material M is a corrugated paper board sheet 50 which extends peripherally of the reel, and is secured in position by a metal strapSl. The sheet 50 is preferably of a very strong multiple ply corrugated paper board, having two or even three corrugated mediums of paper. The sheet 50 may lie somewhat inwardly of the peripheries of the flange plates 30, or if more of the material M is coiled on the reel 10, the sheet 50 may be closer to the peripheries of the flange plates 30. in either event, the sheet 50 serves to protect the material M from damage as by abrasion or impact, and also from damage which may occur due to adverse weather conditions.

There has been provided a reel for heavy duty use, in connection with the storing, shipment and dispensing of heavy weight linerally extending products such as hose and cable. The reel herein disclosed is of econom ical construction, being made of corrugated paper board, substantially entirely. It is therefore extremely economical, while being sufficiently strong to carry such heavy loads. These loads may be carried by the reel both when stacked on a single flange plate, or resting on a peripheral portion of both flange plates, In its preferred form, the reel may be shipped in flattened condition, although the reel may additionally be impregnated with a resinous substance for imparting even greater strength thereto, but a resin-impregnated reel cannot ordinarily be shipped in flattened condition. Significantly, also, the reel construction herein provided includes a reinforcement of corrugated paper board which adds both to the columnar and beam strength of the core. The flange plates are preferably constructed of multiple sub-plates, each of multiple layer corrugated board, for additional strength, the corrugations of one sub-plate being transverse to the corrugations of another sub-plate. In addition, there is herein disclosed a reel in which the material on the reel is protected by an economical yet satisfactory construction.

It will be obvious to those skilled in the art that various changes may be made without departing from the spirit of the invention and therefore the invention is not limited to what is shown in the drawings and described in the specification but only as indicated in the appended claims.

I claim:

1. A heavy duty reel made essentially entirely of paper board comprising:

a generally cylindrical hollow core formed from an initially flat cut and scored blank of corrugated paperboard and comprising a plurality of axially extending panels including a pair of end panels and a series of successive intermediate panels, a locking tab extending from one said end panel having a flap hinged thereto about a fold line transverse to the core axis, a panel adjacent said other end panel having a slot therein of a size to admit said locking tab and flap in overlying relationship and to prevent withdrawal of said locking tab and flap when said flap is out of overlying relationship with said locking tab, said locking tab extending through said slot.

a plurality of integral locking fingers at each end of said core.

a pair of flange plates at each end of said core, each said flange plate having an annular series of slots therein having the locking fingers of said core extending therethrough.

2. A heavy duty reel made essentially entirely of paper board comprising:

a generally cylindrical core having a plurality of integral locking fingers at each end thereof,

a pair of flange plates at each end of said core, each said flange plate having an annular series of slots therein having the locking fingers of said core extending therethrough, and

reinforcing means for providing axial compressive resistance in said hollow core and having panels engaging said flange plates, each said panel of said reinforcing means having slots therethrough in alignment with slots of said flange plates, said locking fingers of said core having flaps integral therewith and engaging the surface of said flange plates, said flaps having locking tabs integral therewith and at least some of the locking tabs extending through aligned slots in said flange plates and in said reinforcing means,

whereby to provide for erection and assembly of said reel by insertion of said locking fingers and locking tabs in said slots of said flange plates and reinforcing means panels and to provide for interlock of the flanges, core and reinforcing means.

3. The reel of claim 2, said reinforcing means comprising a pair of U-shaped members each having a pair of spaced parallel legs with a said panel integral with and extending between said legs, said legs of said U- shaped members having slits therein defining fingers, the legs of each member extending toward the panel of the other member and said fingers being interdigitated.

4. The reel of claim 2, said flange plates each comprising a first sub-plate and a second sub-plate, each subplate comprising a plurality of corrugated paper mediums interposed between and secured to a plurality of flat paper sheets, with the corrugations parallel, and means securing said sub-plates to each other with the corrugations of one sub-plate substantially perpendicular to the corrugations of the other sub-plate.

5. The reel of claim 4, and means for securing axially extending edges of said core comprising a locking tab and a slot.

6. The reel of claim 3, and means for securing axially extending edges of said core comprising a locking tab and a slot,

7. The reel of claim 2, and linearly extending material coiled on said reel between said plates a corrugated paper board sheet extending peripherally of said reel and overlying said coiled material, and means for securing said sheet in position.

8. The reel of claim 7, said reinforcing means in said hollow core consisting essentially of corrugated paper board.

Claims

1. A heavy duty reel made essentially entirely of paper board comprising: a generally cylindrical hollow core formed from an initially flat cut and scored blank of corrugated paperboard and comprising a plurality of axially extending panels including a pair of end panels and a series of successive intermediate panels, a locking tab extending from one said end panel having a flap hinged thereto about a fold line transverse to the core axis, a panel adjacent said other end panel having a slot therein of a size to admit said locking tab and flap in overlying relationship and to prevent withdrawal of said locking tab and flap when said flap is out of overlying relationship with said locking tab, said locking tab extending through said slot, a plurality of integral locking fingers at each end of said core, a pair of flange plates at each end of said core, each said flange plate having an annular series of slots therein having the locking fingers of said core extending therethrough.

2. A heavy duty reel made essentially entirely of paper board comprising: a generally cylindrical core having a plurality of integral locking fingers at each end thereof, a pair of flange plates at each end of said core, each said flange plate having an annular series of slots therein having the locking fingers of said core extending therethrough, and reinforcing means for providing axial compressive resistance in said hollow core and having panels engaging said flange plates, each said panel of said reinforcing means having slots therethrough in alignment with slots of said flange plates, said locking fingers of said core having flaps integral therewith and engaging the surface of said flange plates, said flaps having locking tabs integral therewith and at least some of the locking tabs extending through aligned slots in said flange plates and in said reinforcing means, whereby to provide for erection and assembly of said reel by insertion of said locking fingers and locking tabs in said slots of said flange plates and reinforcing means panels and to provide for interlock of the flanges, core and reinforcing means.

3. The reel of claim 2, said reinforcing means comprising a pair of U-shaped members each having a pair of spaced parallel legs with a said panel integral with and extending between said legs, said legs of said U-shaped members having slits therein defining fingers, the legs of each member extending toward the panel of the other member and said fingers being interdigitated.

4. The reel of claim 2, said flange plates each comprising a first sub-plate and a second sub-plate, each sub-plate comprising a plurality of corrugated paper mediums interposed between and secured to a plurality of flat paper sheets, with the corrugations parallel, and means securing said sub-plates to each other with the corrugations of one sub-plate substantially perpendicular to the corrugations of the other sub-plate.

6. The reel of claim 3, and means for securing axially extending edges of said core comprising a locking tab and a slot.