CA2425065A1 - A sharply bent wood strand molded part - Google Patents

Abstract

A molded wood strand part (14), and a mold (10) and method for making same, wherein the part (14) includes a sharply bent portion (15) having an inside angle of 60 degree or less, and an inside root with a radius of curvature of 0.375 inches or less.

Description

A SHARPLY BENT WOOD STRAND MOLDED PART
BACKGROUND OF THE INVENTION
A. Field of the Invention The present invention relates to wood flake molding.
B. Background of the Art Wood flake molding, also referred to as wood strand molding, is a technique invented by wood scientists at Michigan Technological University during the latter part of the 1970s for molding three-dimensionally configured objects out of binder coated wood flakes having an average length of about 11/a to about 6 inches, preferably about 2 to about 3 inches; an average thickness of about 0.005 to about 0.075 inches, preferably about 0.015 to about 0.030 inches; and an average width of 3 inches or less, most typically 0.25 to 1.0 inches, and never greater than the average length of the flakes.
These flakes are sometimes referred to in the art as "wood strands." This technology is not to be confused with oriented strand board technology (see e.g., U.S.
Patent No.

3,164,511 to Elmendorfj wherein binder coated flakes or strands of wood are pressed into planar objects. In wood flake or wood strand molding, the flakes are molded into three-dimensional, i.e., non-planar, configurations.
In wood flake molding, flakes of wood having the dimensions outlined above are coated with MDI or similar binder and deposited onto a metal tray having one open side, in a loosely felted mat, to a thickness eight or nine times the desired thickness of the final part. The loosely felted mat is then covered with another metal tray, and the covered metal tray is used to carry the mat to a mold. (The terms "mold" and "die", as well as "mold die", are sometimes used interchangeably herein, reflecting the fact that "dies" are usually associated with stamping, and "molds" are associated with plastic molding, and molding of wood strands does not fit into either category.) The top metal tray is removed, and the bottom metal tray is then slid out from underneath the mat, to leave the loosely felted mat in position on the bottom half of the mold. The top half of the mold is then used to press the mat into the bottom half of the mold at a pressure of approximately 600 psi, and at an elevated temperature, to "set" (polymerize) the MDI
binder, and to compress and adhere the compressed wood flakes into a final three-dimensional molded part. The excess perimeter of the loosely felted mat, that is, the portion extending beyond the mold cavity perimeter, is pinched off where the part defining the perimeter of the upper mold engages the part defining perimeter of the lower mold cavity. This is sometimes referred to as the pinch trim edge.
U.S. Patents 4,440,708 and 4,469,216 disclose this technology. The drawings in Patent U.S. 4,469,216 best illustrate the manner in which the wood flakes are deposited to form a loosely felted mat, though the metal trays are not shown. By loosely felted, it is meant that the wood flakes are simply lying one on top of the other in overlapping and interleaving fashion, without being bound together in any way. The binder coating is quite dry to the touch, such that there is no stickiness or adherence which hold them together in the loosely felted mat. The drawings of Patent U.S. 4,440,708 best illustrate the manner in which a loosely felted mat is compressed by the mold halves into a three-dimensionally configured article (see Figs. 2-7, for example).
This is a different molding process as compared to a molding process one typically thinks of, in which some type of molten, semi-molten or other liquid material flows into and around mold parts. Wood flakes are not molten, are not contained in any type of molten or liquid carrier, and do not "flow" in any ordinary sense of the word.
Hence, those of ordinary skill in the art do not equate wood flake or wood strand molding with conventional molding techniques.
Heretofore, artisans have refrained from designing three-dimensionally curved parts having sharp bends, that is bends where the part is bent sharply back on itself at an inside angle of 60° or less, and where the root of the bend has a radius of curvature of less than 3/8 of an inch (0.375 inches). It has been thought that such a bend is simply too severe to allow the wood strands to properly consolidate in the area of the sharp bend, i.e. without leaving voids or other surface irregularities in the vicinity of the bend.
For similar reasons, it has been thought that it would not be possible to form a~
part having a portion, for example an edge portion, with a deep draw and a small draft angle, that is a depth from top to bottom of 1 3/8 inches (1.375 inches) or more, at a draft angle of 10° or less. The part overall may have had a top to bottom distance of greater than 1.375 inches, but no portion with a draft angle (angle of the side of the portion to vertical) of 10° or less combined with a draw of 1.375 inches or greater.
SUMMARY OF THE INVENTION
We have surprisingly discovered that the loosely felted wood strand or flake mat can be bent sharply back on itself during the molding process, to form a part having an inside angle of 60° or less, where the radius of curvature at the root of the angle of _2_ 0.375 inches or less, and even more surprisingly that we can even form to an inside angle of 50° or less, and/or to a radius of curvature at the root of 0.125 inches or less.
This adds considerable versatility to the design of wood strand molded parts.
Indeed, I have surprisingly found that I can form parts with portions at a draw of 1.375 inches or more and a draft angle of 10° or less, indeed even with a draw of 2.0 inches or more and/or a draft angle of 5° or Less. These results were surprising and unexpected for wood strand molding.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a side elevational cross sectional view of the spaced upper and lower mold halves with a loosely felted mat of wood flakes positioned therebetween.
Fig. 2 is the same view of Fig. 1 with the mold closed, whereby the wood flakes are consolidated, compressed, and cured under heat and pressure to form a molded wood flake part.
Fig. 3 is a fragmentary cross sectional view of the sharply bent portion of the part formed in Figs. 1 and 2.
Fig. 4 is a cross-sectioned perspective view of a portion of the part formed in the wood strand molding process illustrated in Figs. 1 and 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
For purposes of description herein, the terms "upper," "lower," "right,"
"left,"
"rear " "front " "vertical " "horizontal " and derivatives thereof shall relate to the > > > >
invention as orientated in Fig. 1. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary.
It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
The reference number 10 (Fig. 1) generally designates a mold of the present invention. The mold 10 is used in a method of forming a loosely felted mat 11 of wood flakes 12 into a molded wood flake part 14 (Fig. 2). The mold 10 includes a top mold die 16 and a bottom mold die 18. The top mold die 16 includes a surface 20, and the bottom mold die 18 includes a surface 26. The surface 20 of the top mold die 16 and the surface 26 of the bottom mold die 18 deftne a cavity 30 therebetween.
In the illustrated example, the molded wood flake part 14 is made by positioning a loosely felted mat 11 of wood flakes 12 on the bottom mold die 18 (Fig. 1).
The top mold die 16 and the bottom mold die 18 are then brought together (Fig. 2) and heat and pressure are applied to the felted mat 11. The felted mat 11 is thereby compressed and cured into the molded wood flake part 14.
Part 14 is designed to bend sharply back on itself at 15, along the side edges of the part (Figs. 2, 3 and 4). The inside corner or root of bent portion IS
includes a sharply rounded portion 17 having a radius of curvature R. The inside angle theta (0) of bend 15 is the angle formed by the intersection of the extensions of the generally flat portions of the inside surface 19 of bent portion 15. Inside surface 19 begins at approximately the point at which the curved root 17 begins to flatten out on either side of root 17.
The term "sharply bent" as used in this invention refers to a bent portion 15 where the inside angle theta (~) is less than 60°, and the radius of curvature of the root of the inside of the bent portion 15 is 0.375 inches or less. The point at which the radius of curvature of the inside surface of bent portion 15 begins to exceed 0.375 inches, is the point at which inside surface 19 begins.
It is particularly surprising that such a sharply bent part can be made where the bent portion 15 has an inside depth d (Fig. 4) of 1-inch or more, and is even more surprising when the sharply bent portion 15 is formed to create an inside depth d (Fig. 4) of 1 1/a inches or greater. The depth d (Fig. 4) can be thought of as the depth of a channel defined by sharply bent portion 15.
I have discovered even more surprisingly that I can form a part having an inside angle of 50° or less, and/or a radius of curvature at the root of the bent part of 1/8 of an inch (0.125 inches) or less. Thus, one part has been shaped to an inside angle of 50° at a root radius of curvature of 0.125 inches, with the part being drawn to a depth of 1.373 inches. Yet another part was shaped to an inside angle of approximately 42°, with a radius of curvature at the inside root of the bend of 0.312 inches.
A related, yet separate aspect of the invention is the relationship between the depth of draw of the part and the draft angle used. A part with a portion which is sharply bent back on itself will tend to have a steep, i.e. small, draft angle. The depth of draw "h" of the part, or more precisely of any portion of the part, is the depth of that portion from top to bottom. The draft angle alpha (a) of that portion of the part is the angle which the steepest portion of the part makes with respect to the vertical. This draft angle must be greater than 0° in order to be able to remove the molded part from a simple mold, i.e. a mold that does not require cams.
I have surprisingly discovered that I can form a part with a portion having a depth of draw h of 1 3/8 inches or more, at a draft angle a of 10° or less. Indeed, I
have surprisingly found that I can form parts to a depth of draw h of 2 inches or more and a draft angle a of 5° or less. One part has been formed to a depth of draw of 2.5 inches at a draft angle of 3.1 ° . Another was formed to a depth of draw of almost 3 inches, at a draft angle of 3 . 8 ° .
It is surprising that the wood flakes can be folded or forced to slide or bend down into deeply drawn portions of the part during the molding process. The parts are preferably formed to a thickness from '/ inch to 1 inch, preferably 3/8 of an inch to 5/8 of an inch. Parts can be made which are thicker, but they take longer to cure in the mold. While some parts could probably be made to thicknesses of less than '/
of an inch, it is difficult to do so without encountering an unacceptable number of rejects.
The wood flakes 12 used in creating the molded wood flake part 14 can be prepared from various species of suitable hardwoods and softwoods used in the manufacture of particleboard. Representative examples of suitable woods include aspen, maple, oak, elm, balsam fir, pine, cedar, spruce, locust, beech, birch and mixtures thereof. Aspen is preferred.
Suitable wood flakes 12 can be prepared by various conventional techniques.
Pulpwood grade logs, or so-called round wood, are converted into wood flakes 12 in one operation with a conventional roundwood flaker. Logging residue or the total tree is first cut into fingerlings in the order of 2-6 inches long with a conventional device, such as the helical comminuting shear disclosed in U.S. Patent No. 4,053,004, and the fingerlings are flaked in a conventional ring-type flaker. Roundwood wood flakes 12 generally are higher quality and produce stronger parts because the lengths and thickness can be more accurately controlled. Also, roundwood wood flakes 12 tend to be somewhat flatter, which facilitates more efficient blending and the logs can be debarked prior to flaking which reduces the amount of less desirable fines produced during flaking and handling. Acceptable wood flakes 12 can be prepared by ring flaking fingerlings and this technique is more readily adaptable to accept wood in poorer form, thereby permitting more complete utilization of certain types of residue and surplus woods.
Irrespective of the particular technique employed for preparing the wood flakes 12, the size distribution of the wood flakes 12 is quite important, particularly the length and thickness. The wood flakes should have an average length of about 1'/ inch to about 6 inches and an average thickness of about 0.005 to about 0.075 inches.
The average length of the wood flakes is preferably about 2 to about 3 inches. In any given batch, some of the wood flakes 12 can be shorter than 1'/ inch, and some can be longer than 6 inches, so long as the overall average length is within the above range. The same is true for the thickness.
The presence of major quantities of wood flakes 12 having a length shorter than about 1'/a inch tends to cause the felted mat 11 to pull apart during the molding step.
The presence of some fines in the felted mat 11 produces a smoother surface and, thus, may be desirable for some applications so long as the majority of the wood flakes, preferably at least 75 % , is longer than 1 1 /8 inch and the overall average length is at least 11/ inch.
Substantial quantities of wood flakes 12 having a thickness of less than about 0.005 inches should be avoided, because excessive amounts of binder are required to obtain adequate bonding. On the other hand, wood flakes 12 having a thickness greater than about 0.075 inch are relatively stiff and tend to overlie each other at some incline when formed into the felted mat 11. Consequently, excessively high mold pressures are required to compress the wood flakes 12 into the desired intimate contact with each other. For wood flakes 12 having a thickness falling within the above range, thinner ones produce a smoother surface while thick ones require less binder. These two factors are balanced against each other for selecting the best average thickness for any particular application. The average thickness of the wood flakes 12 preferably is about 0.015 to about 0.25 inches, and more preferably about 0.0020 inch.
The width of the wood flakes 12 is less important. The wood flakes 12 should be wide enough to ensure that they lie substantially flat when felted during mat formation.
The average width generally should be about 3 inches or less and no greater than the average length. For best results, the majority of the wood flakes 12 should have a width of about 1/16-inch to about 3 inches, and preferably 0.25 to 1.0 inches.

The blade setting on a flaker can primarily control the thickness of the wood flakes 12. The length and width of the wood flakes 12 are also controlled to a large degree by the flaking operation. For example, when the wood flakes 12 are being prepared by ring flaking fingerlings, the length of the fingerlings generally sets the maximum lengths. Other factors, such as the moisture content of the wood and the amount of bark on the wood affect the amount of fines produced during flaking.
Dry wood is more brittle and tends to produce more fines. Bark has a tendency to more readily break down into fines during flaking and subsequent handling than wood.
While the flake size can be controlled to a large degree during the flaking operation as described above, it usually is necessary to use some sort of classification in order to remove undesired particles, both undersized and oversized, and thereby ensure the average length, thickness and width of the wood flakes 12 are within the desired ranges. When roundwood flaking is used, both screen and air classification usually are required to adequately remove both the undersize and oversize particles, whereas fingerling wood flakes 12 usually can be properly sized with only screen classification.
Wood flakes 12 from some green wood can contain up to 90 % moisture. The moisture content of the mat must be substantially less for molding as discussed below.
Also, wet wood flakes 12 tend to stick together and complicate classification and handling prior to blending. Accordingly, the wood flakes 12 are preferably dried prior to classification in a conventional type drier, such as a tunnel drier, to the moisture content desired for the blending step. The moisture content to which the wood flakes 12 are dried usually is in the order of about 6 weight % or less, preferably about 2 to about 5 weight % , based on the dry weight of the wood flakes 12. If desired, the wood flakes 12 can be dried to a moisture content in the order of 10 to 25 weight % prior to classification and then dried to the desired moisture content for blending after classification. This two-step drying may reduce the overall energy requirements for drying wood flakes 12 prepared from green woods in a manner producing substantial quantities of particles which must be removed during classification and, thus, need not be as thoroughly dried.
To coat the wood flakes 12 prior to being placed as a felted mat 11 within the cavity 30 within the mold 10, a known amount of the dried, classified wood flakes 12 is introduced into a conventional blender, such as a paddle-type batch blender, wherein predetermined amounts of a resinous particle binder, and optionally a wax and other additives, is applied to the wood flakes 12 as they are tumbled or agitated in the blender.
Suitable binders include those used in the manufacture of particle board and similar pressed fibrous products and, thus, are referred to herein as "resinous particle board binders." Representative examples of suitable binders include thermosetting resins such as phenolformaldehyde, resorcinol-formaldehyde, melamine-formaldehyde, urea-formaldehyde, urea-furfuryl and condensed furfuryl alcohol resins, and organic polyisocyantes, either alone or combined with urea- or melamine-formaldehyde resins.
Particularly suitable polyisocyanates are those containing at least two active isocyanate groups per molecule, including diphenylmethane diisocyanates, m-and p-phenylene diisocyanates, chlorophenylene diisocyanates, toluene di- and triisocyanates, triphenylmethene triisocyanates, diphenylether-2,4,4'-triisoccyanate and polyphenylpolyisocyanates, particularly diphenylmethane-4,4'-diisocyanate. So-called MDI is particularly preferred.
The amount of binder added to the wood flakes 12 during the blending step depends primarily upon the specific binder used, size, moisture content and type of the wood flakes 12, and the desired characteristics of the part being formed.
Generally, the amount of binder added to the wood flakes 12 is about 2 to about 15 weight % , preferably about 4 to about 10 weight % , as solids based on the dry weight of the wood flakes 12. When a polyisocyanate is used alone or in combination with a urea-formaldehyde resin, the amounts can be more toward the lower ends of these ranges.
The binder can be admixed with the wood flakes 12 in either dry or liquid form.
To maximize coverage of the wood flakes 12, the binder preferably is applied by spraying droplets of the binder in liquid form onto the wood flakes 12 as they are being tumbled or agitated in the blender. When polyisocyantes are used, a conventional mold release agent preferably is applied to the die or to the surface of the felted mat prior to pressing. To improve water resistance of the part, a conventional liquid wax emulsion preferably is also sprayed on the wood flakes 12 during the blinding step. The amount of wax added generally is about 0.5 to about 2 weight % , as solids based on the dry weight of the wood flakes 12. Other additives, such as at least one of the following: a coloring agent, fire retardant, insecticide, fungicide, mixtures thereof and the like may also be added to the wood flakes 12 during the blending step. The binder, wax and other additives, can be added separately in any sequence or in combined form.
_g_ The moistened mixture of binder, wax and wood flakes 12 or "furnish" from the blending step is formed into a loosely-felted, layered mat 11, which is placed within the cavity 30 prior to the molding and curing of the felted mat 11 into molded wood flake part 14. The moisture content of the wood flakes 12 should be controlled within certain limits so as to obtain adequate coating by the binder during the blending step and to enhance binder curing and deformation of the wood flakes 12 during molding.
The presence of moisture in the wood flakes 12 facilitates their bending to make intimate contact with each other and enhances uniform heat transfer throughout the mat during the molding step, thereby ensuring uniform curing. However, excessive amounts of water tend to degrade some binders, particularly urea-formaldehyde resins, and generate steam which can cause blisters. On the other hand, if the wood flakes 12 are too dry, they tend to absorb excessive amounts of the binder, leaving an insufficient amount on the surface to obtain good bonding and the surfaces tend to cause hardening which inhibits the desired chemical reaction between the binder and cellulose in the wood. This latter condition is particularly true for polyisocyanate binders.
Generally, the moisture content of the furnish after completion of blending, including the original moisture content of the wood flakes 12 and the moisture added during blending with the binder, wax and other additives, should be about 5 to about 25 weight % , preferably about 8 to about 12 weight % . Generally, higher moisture contents within these ranges can be used for polyisocyanate binders because they do not produce condensation products upon reacting with cellulose in the wood.
The furnish is formed into the generally flat, loosely-felted, mat 11, preferably as multiple layers. A conventional dispensing system, similar to those disclosed in LT.S.
Pat. Nos. 3,391,223 and 3,824,058, and 4,469,216 can be used to form the felted mat 11. Generally, such a dispensing system includes trays, each having one open side, carried on an endless belt or conveyor and one or more (e.g., three) hoppers spaced above and along the belt in the direction of travel for receiving the furnish.
When a mufti-layered felted mat 11 is formed, a plurality of hoppers usually are used with each having a dispensing or forming head extending across the width of the carriage for successively depositing a separate layer of the furnish as the tray is moved beneath the forming heads. Following this, the tray is taken to the mold to place the felted mat within the cavity of bottom mold, by sliding the tray out from under mat.
_9_ In order to produce molded wood flake parts 14 having the desired edge density characteristics without excessive blistering and springback, the felted mat should preferably have a substantially uniform thickness and the wood flakes 12 should lie substantially flat in a horizontal plane parallel to the surface of the carriage and be randomly oriented relative to each other in that plane. The uniformity of the mat thickness can be controlled by depositing two or more layers of the furnish on the carriage and metering the flow of furnish from the forming heads.
Spacing the forming heads above the carriage so the wood flakes 12 must drop about 1 to about 3 feet from the heads en route to the carriage can enhance the desired random orientation of the wood flakes 12. As the flat wood flakes 12 fall from that height, they tend to spiral downwardly and land generally flat in a random pattern.
Wider wood flakes 12 within the range discussed above enhance this action. A
scalper or similar device spaced above the carriage can be used to ensure uniform thickness or depth of the mat, however, such means usually tend to align the top layer of wood flakes 12, i.e., eliminate the desired random orientation. Accordingly, the thickness of the mat that would optimally have the nominal part thickness 100 preferably controlled by closely metering the flow of furnish from the forming heads. The mat thickness that would optimally have the nominal part thickness I00 used will vary depending upon such factors as the size and shape of the wood flakes 12, the particular technique used for forming the mat 11, the desired thickness and density of the molded wood flake part 14 produced, the configuration of the molded wood flake part 14, and the molding pressure to be used.
Following the production of the felted mat 11 and placement of the felted mat within the cavity 30 of the mold 10, the felted mat 11 mat is compressed and cured under heat and pressure when the top mold die 16 engages the bottom mold die 18.
The felted mat 11 is then compressed and cured between the top mold die I6 and the bottom mold 18 to become the molded wood flake part 14. After the molded wood flake part 14 is produced by the method of the present invention, any flashing is removed by conventional means.
The resulting part I4 is formed with very sharp bent portions IS at its edges.
The ability to design said sharply bent portions 15 into the part results in a part with greatly added strength in the areas of the bent portions. Part 14 which is shown has a depth of draw at its perimeter of approximately 1.5 inches and a draft angle of 10°. Part 14 as shown in Fig. 4 might be used as a tractor seat, for example, or as the shell for making a tractor seat.
The above description is that of the preferred embodiment only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiment described above is merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents.

Claims (19)

The invention claimed is:

1. A wood strand molded part, molded from a loosely felted mat of binder coated wood flakes having an average length of about 1 1/4 to about 6 inches, an average thickness of about 0.005 to about 0.075 inches, and an average width of 3 inches or less, said average width never being greater than said average length of said flakes, wherein said part has been molded to include a sharply bent portion having an inside angle of 60°
or less, and a radius of curvature at the root of the inside angle of 0.375 inches or less.

2. The wood strand molded part of claim 1 wherein said sharply bent portion has an inside depth of at least 1 inch.

3. The wood strand molded part of claim 1 wherein said sharply molded portion has an inside depth of at least 1 1/2 inches.

4. The wood strand molded part of claim 1 wherein said wood flakes have an average length of about 2 to about 3 inches, an average thickness of about 0.015 to about 0.030 inches, and an average width of 0.25 to 1.0 inches.

5. The wood strand molded part of claim 4 wherein said sharply bent portion has an inside depth of at least 1 inch.

6. The wood strand molded part of claim 4 wherein said sharply molded portion has an inside depth of at least 1 1/2 inches.

7. A mold for forming a wood strand molded part, molded from a loosely felted mat of binder plated wood flakes having an average length of about 1 1/4 to about 6 inches, an average thickness of about 0.005 to about 0.075 inches, and an average width of 3 inches or less, said average width never being greater than said average length of said flakes, said mold being configured to form a part having a sharply bent portion having an inside angle of 60° or less, and a radius of curvature at the root of the inside angle of 0.375 inches or less.

8. The mold of claim 7 which is configured to form said sharply bent portion to an inside depth of at least 1 inch.

9. The mold of claim 7 which is configured to form said sharply molded portion to an inside depth of at least 1 1/2 inches.

10. A wood strand molded part, molded from a loosely felted mat of binder plated wood flakes having an average length of about 1 1/4 to about 6 inches, an average thickness of about 0.005 to about 0.075 inches, and an average width of 3 inches or less, said average width never being greater than said average length of said flakes, wherein said part has been molded to include a portion with a depth of draw of 1.375 inches or more and a draft angle of 10° or less.

11. The wood strand molded part of claim 10 in which said portion is drawn to a depth of 2 inches or more.

12. The wood strand molded part of claim 11 in which said portion has a draft angle of 5° or less.

13. The wood strand molded part of claim 12 wherein said wood flakes have an average length of about 2 to about 3 inches, an average thickness of about 0.015 to about 0.030 inches, and an average width of 0.25 to 1.0 inches.

14. The wood strand molded part of claim 10 in which said portion has a draft angle of 5° or less.

15. The wood strand molded part of claim 10 wherein said wood flakes have an average length of about 2 to about 3 inches, an average thickness of about 0.015 to about 0.030 inches, and an average width of 0.25 to 1.0 inches.

16. A mold for forming a wood strand molded part, molded from a loosely felted mat of binder plated wood flakes having an average length of about 1 1/4 to about 6 inches, an average thickness of about 0.005 to about 0.075 inches, and an average width of 3 inches or less, said average width never being greater than said average length of said flakes, said mold being configured to form a part having a portion with a depth of draw of 1.375 inches or more and a draft angle of 10° or less.

17. The mold of claim 15 which is configured to form said portion to a depth of draw of 2 inches or more.

18. The mold of claim 17 which is configured to form said portion to a draft angle of 5° or less.

19. The mold of claim 16 which is configured to form said portion to a draft angle of 5° or less.