CA2022900A1 - System for oriented strand layup - Google Patents

Abstract

SYSTEM FOR ORIENTED STRAND LAYUP
ABSTRACT OF THE DISCLOSURE
A system for continuously forming a multi-layer, oriented strand layup from at least two, and preferably four, layup feed sources. At least first and second layups are simultaneously formed, overlapping one on top of the other in zig-zag patterns on a longitudi-nal, sid-to-side moving conveyor trough. The top of the bottom layer is formed at the same time as the bottom of the top layer, and an angled base on which the strands fall is thereby created which has a consistent strand angle across the interface of the layers. This care-fully coordinated layup motion forms a strand mat with a continuous average strand angle throughout its layup feed interface(s), thereby forming, after heating and compression thereof, an elongate compos-ite product having consistent strength properties.

Description

2~2~

SYSTEM FOR ORIENTED STRAND LAYUP

CXOSS-REFERENCE TO RELAT~SD APPLICATIONS
This is a continuation-in-part of copending Application Serial No. 07/389,405, filed August 4, 1989, which is a divisional of Applica-tion Serial No. 07/154,440, filed February 9, 1988, now U.S. Patent 4,872,544 (l544), which in turn is a continuation of Serial No.
06/882,372, filed July 7, 1986, now abandoned, which in turn is a con~
tinuation of Seriial No. 06/738,542, filed May 28, 1985, now U.S. Patent 4,706,799 (~799), which in turn is a divisional of Serial No. 06/547,578, filed November 1, 1983, now U.S. Patent 4,563,237 (~23?). Each o~ the applications, patents and other publications mentioned anywhere in this disclosure is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
The present invention relates to continuous processes and apparatuses ~or depositing elongate members in a layup wtth each member oriented substanti~y in a longitudinal direction OI the layup.
The invention further relates to such processes wherein the mat thereby produced in the trough is formed ~rom a plurality of layup eeds. `
A product containing oriented elongated strands is disclosed in Barnes, U5. Patent No. 4,061,819 (~819), for example. The process of the ~819 patent de~sit-s elongate wood strands with ~their ends in`
overlapping relationship to provide a roughly uni~orm distribution along the length of the trough. The strands are subsequently com-pressed and heated to cure their resin coatings to thereby form a structural product having a strength equal to prime structural lumber Mats produced by processes of the ~819 patent can have the strands thereof positioned at excessively large angles either vertically or "

~:R~

22~

laterally to the longitudinal direction of the form. The composite product thereby produced thus has less than its full strength potential.
When composite strand products are prepared by batch meth-ods, the strands can be positioned by hand with no signii'icant loss in strength due to disoriented strands. However, when composite strand prodwts are made using a continuous process, the strands are usually deposited on a moving conveyor bel~ so that the ends thereor overlap.
An example thereof is shown in Champigny, U.S. Patent 3,493,021 (~021). The strands are deposited at angles similar in both magnitude and direction in a "card-decking~ orientation wherein each s~rand is at an angle to the longitudinal direction of the layup mat. Excessive vertical strand angle in this mat can result in undesirable vertical curvature in the resulting continuously compressed product.
The processes and apparatuses disclosed in the parent ~544, ~799 and '237 patents remedy thes,e disadvantages of the prior art. The process~s disclosed therein ~ontinuously form a product from elongate members at least about a foot in length which are oriented, com-pressed and bonded. The elongate members are depo~ited on a moving carrier and oriented substantially parallel to the direction of move-ment Or the carrier and on the carrier over a length thereof that is a~
least as long as about one and a haLr times the length of the elongate members and is at least as long as about thirty times the final thick-ness of the compressed, composite product.
~ erore laying these strands in a side-by-side lengthwise dimen-sion in the trough layup they are coated with an adhesive. The strand layup mat is then conveyed to a press where the arranged strands are heated and compressed to thereby rorm a high~trength dimensional comp~$ite product. Examples Or~ belt presses are those disclosed in Churchland, U.S. Patent 4,517,148 (~148) and copending U.S. Appli~a-tion Serial No. 07/456,657, riled December 29, 1989 (Canadian applica-tion Serial No~ 2,006,9g~-3, filed December 29, 1989). The press can incorporate a heating device to heat the strand matefial during its passage through the press and thereby cure the adhesive, and an example thereoî is the microwave heating device shown in Churchland, U.S. Patent 4,456,498.

2 ~

Two or more of these layup systems have been used in the prior art to ~orm a single layup mat. When used though, the interface between the two layups is prone to strand alignment inconsistencies.
This is because the random positioning of strands in the extreme top and bottom in each of the layups creates a different average strand angle during the compre~sion process. The strands in the mat tend to lie at an angle whose tangent, when defined by referring to Figure 2 of the ~237 patent, is equal to Z/Y. In contrast, the strands or parts thereof that are on the very top or bottom are compressed to an angle equal to zero since they are compressed flat against the platens.
When two such layups are formed and placed one on top o~ the other, the interface between them creates a region of strands where the average strand angle is slightly more parallel to the product axis of the buL" of the layup. The consistent strength properties of the final product (PSL) are a function of the consistent manu~acturing parame-ters insluding strand angle. This internal variation affects a band of product about one inch thic~ which can be over fifty percent of the re-manufactured product depth. This can affect all strength proper-ties across the beam thereby produced and perhaps most importantly ~he modulus of elasticity (MOE). This can also induce a remembered stress of the type described in the ~148 patent.
It is also old to provide a single feed position which is two strands wide. In other words, strands shorter than that disclosed in the '544 patent can be conveyed on a conveyor which is slightly more than two strand lengths wide and conveys two columns of these strar~ds generally simultaneously towards the trough. The strands are thus fed in two places onto the infeed drum or the infeed conveyor.
SUMh1~RY OF 1~ INVEN~ON
Acdordingly, it is a principal object o~ the present invention to provide a system for continuously forming a multilayer layup from at least two layup sources, which system does not suffer from strand alignment and consistency problems.
It is a iurther object of the present invention to pro~ide a pro-cess for making composite products from elongate strands which - 2~2~

products have consistent superior mechanical properties throughout their depths.
Directed to achieving these ob~ects, an improved system for forming an oriented strand layup is disclosed herein. This system includes, in a preierred embodiment thlereof, four layup feeds, each feeding simultaneously onto a single conveyor belt. Each of the four layup feeds includes a layup table for ~eeding directly onto the con-veyor belt. The ~our layup tables are physically secured together, and a drive system propels them back and forth along a common track parallel to the conveybr belt and while the tables convey the adhesive-coated strands laterally onto the belt. The strands are dropped individually, efiectively one at a time, over a distance larger than the strand length onto the conveyor belt and in a zig-zag pattern thereon. Each oi the four strand layups is formed at the same time such that the top oi the bottom layer is iormed at the same time as the ~ottom of the ad~acent top layer. A continuous average strand angle throughout the interiaces oi the layers is thereby deiined. The strand mat thereby formed on the belt from the four overlapping layups is then pressed and heated. This consistent strand angle ensures that the iinal compressed product has consistent mechanical properties throughout its cross~ectional depth.
Other ob~ects and advantages o~ the present invention wlll become more apparent to those p~rsons having ordinary skill in the art to which the present invention pertains from the foregoing des~ription taken into conjunction with the accompanying drawings.
B~ DESCRIPllON OF THE DRAWINGS
Figure 1 is a top plan view o~ a system of the present invention having iour layup ~eeds.
Fig~re 2 is an enlarged cross-sectional view taken along line 2-2 of Figure 1.
Figure 3 is an enlarged cross-sectional view taken along line 3-3 of Figure 1.
Figure 4 is an enlarged cross~ectional view taken along line 4-4 ot Figure 1.

' ~` ' '' ' 2~2~

Figure 5 is a top plan view of the oscillating table assembly o~
the system of Figure 1.
Figure 6 is a side elevational view of the assembly of Figure 5.
Flgure 7 is a top plan view o~ the conveyor belt of the system of Figure 1.
Figure 8 is a fragmentary, perspective view of one of the con-veying tables of the system of Figure ~ illustrating the flow of elon-gate strands relative to it.
Figure 9 is a longitudinal schematic view i~ong the layup trough of the system of Figure 1 showing the mass flow contributions from each of the layup feeds as a lunction o~ position along the trough.
Figure 10 is a longitudinal view showing the mass o~ strands in the layup trough of the system of Figure 1 and during a continuous layup process of the present invention.
Figure 11 is a central cross-sectional view o~ a mat formed by the system of Figure 1 and on the layup trough thereof, showing the source of layup feeds theretor.
DET~ D DESCE~IPTION OF PREFERRED ~;
EMBODn~ENTS OF THE iNVENTlON
Referring to Figure 1 a system of the present invention is illus-trated therein generally at 20. System 20 includes ~our layup feeds which are essentially identical and designated in the drawing by refe~
ence numerials 22, 24, 26, and 28, each of them feed~ng simultaneously onto ia conveyor trough shown generally at 30 and including a wig-wag works. While the top oi the tro~gh 30 is fixed, the bottom edge w~wags back and forth by lever arms on either side thereof as best shown in Flgure 4. The strand mat 32 thereby continuously formed (see Fides 10 and Il) on the trough 30 is continuously conveyed lon-gitudinally to a press iassembly shown gener~y at 34. At the press assembly 34 the mat 32 is continuously compressed and heated to form the fini~ compcsite product. Since each of the four layup feeds is generally the same, descriptions of one can be applied to the other three. It will further be appreciated ~hat, while four feeds (22, 24, 26 and 28) are shown, generally any number of intertwining feeds greater ~:, ~ 2~

than one can be used pursuant to this invention. The paths of the elongate strands 36 are illustrated by the arrows in Figure 1. The four arrows at the boetom o~ the drawing show that each of the paths is generally separate until generally when the strands 36 are deposited on the conveyor trough 30. The flow and the operations on the strands will now be discussed.
As best shown in Figure 2, stacks of veneer 38 are conveyed to the system. When they move into the position 42, they ar~ beneath the vacuum lifting system shown generally at ~4. Thls system 44 essentially comprises an upside-down conveyor 46 wherein the belts thereof have holes opening down from a vacuum box 48. When the conveyor 46 is pushed down onto the top d the veneer stack 40 and there is a constant vacuum in the belt, the top sheet o~ ven~er is picked up. The upside-down conveyor 46 is indexed up, picking the top sheet of veneer up with it. The sheet of veneer directly beneath it is not piclced up, however, because there is no vacuum pressure on it. This procedure is relatively slow as compared to other procedures of this system. It takes, ror example, about a second to move up, a second to move down and a second to move back up. The upside-down conveyor 46 with the single sheet of veneer thereby picked up indexes forward, thereby transporting with vacuum suction the sheet of veneer to the next table, which is a six-~oot long roll case 52. At an appropriate point, a physical position sensor, such as an electric eye (not shown), deteets that the transported sheet is clear o~ the sheet beneath it on the ta~le, and the upper conveyor 46 then indexes down.
More particularly, a series of arms pushes the veneer sheet away from the vacuum belt. Once the sheet separates by more than about an inch oY air, the vacuum suction ~orce can n4 longer suck the veneer sheet back up, and the veneer sheet drops onto the conveyor 52. This conveyor 52 and all conveyances beyond it are constantly moving.
As soon as the veneer sheet drops down onto the conveyor 52 ~he sheet is moving up the conveyor slope 54, travelling at only a few fee~, perhaps fiY~e or ten ~eet, per minute. The vacuum box 48 then indexes down, picks up the next sheet and brings it forward. The next sheet o~ veneer then sits poised above the moving rirst sheet until the ~, - 2~2~

îirst sheet has moved clear out from underneath as detected by the position sensor. The second veneer sheet is then dropped down just behind the first sheet, and the process continued. A series of veneer sheets with preferably about an inch space between them moYlng up the conveyor is thereby provided. The sheets are moved by the con-veyor 54 to the clipper or rotary strand0r shown generally at 56 at the top of the slope.
At the rotary strander 56 the sheets are pinched between upper and lower pinch belts, whieh pinch the veneer and constantly move it towards the strander plate. The s~rander 56 comprises an anvil across which a long, about a one hundred and ten inch long, knife passes across all at once and clips off in one swift motion a strand of veneer approximately one-half inch wide. These strands are about one hun-dred and two inches long, which is the length of the veneer sheets.
This clipping is a continuous process, and it happens so quickly that the conveying motion of the veneer is essentially not required to StOp The veneer sheet indexes out another one-ha~ inch before the next blade comes around. Mechanical linkages ensure that the indexing out is always one-halI inch, irrespective of the speed o~ the conveyor 52 and/or the clipper S~. Thus, the conveyor 52 and the clipper 56 are mechanicaUy connected, so that the speed of the conveyor and the rotational speed OI the clipper dependably and ei~iciently create a series oI on~half inch wide strands. Their speed and the speed OI the rest o~ the system 20 are determined by a computer to provide a con-stant mass flow rate.
The clipped strands fall down from the rotary strander 56 onto a cylindrical beltline assembly 60 which sc~ots them onto the strander out~eed conveyor 62. At that point the axes or the strands are paral-lel to the axes of the outîeed conveyor pulleys or drive drums. The system then makes a turn, and the strands drop onto the next con-veyor at an angle of about thirty degrees to the axes of all of the drive pulleys and underneath oi the ~elt 6. The strands drop ~elow and are immediately covered by the top hold-down belt 63. They are moved towards an adjustable gap 64, which is a physical path break beneath the tQp belt. The top belt 63 goes over the gap 6~, and the - 2 ~

strands are passed at an angle from one side of the gap to the other, bein held down by the top belt. The strands that are too short drop through the gap 64 into a short strand, hog feed tnfeed conveyor 66, which is a vibrating conveyor that moves the short strands away to a location where they are hogged for fuel or made into pulp chips. As an example, strands that are only a foot long are too short and any-thing in normal operation a~out two feet is conveyed away. In some circumstances, ~he gap 62 would be set ~or one ~oot strand lengths.
Instead of this belt hol~down system, pinch rollers can be used on top of gap rollers such that the strands are held by pinch roUers and passed from one pinch roll to the next. This is a known proce-dure, and reierence is hereby made to Churchland, U.S. Patent 4,546,886. The belt system o~ the present invention, however, is a more gentle way of handling the strands than is the pinch roll system.
Subsequently and referring to Figure 3, the strands are con-veyed to the inner feed glue spreader shown generally at 70 having a top roll glue tank 71a, a waste water tank 71b and a bottom roll glue tank 71c. They are still at their previously-mentioned thirty degree angle which allowed them to pass across the gap 64 of the short strand eliminator. In the glue spreader 70 the strands 36 are covered with a suitable glue or adhesive, such as a standard phenol-formaldehyde glue having a small waac component. From the glue spreader ~0 they are deposited on the chain bar outfeed conveyor shown generally at 72, still travelling at the thirty degree angle, which advantageously glves them a longitudinal component of travel.
The parallel chain bars 7~ move from left to right, and the strands 36 fall oif the series of head or nose pulleys or discs 76, as shown in Fig-ure 8~ and fall straight down onto the oscillating table 80. The strands 36 fall on to all o~ the discs 76 at the same time and thus are parallel to the center points oi the discs. They are deposi~ed down onto the oscillating table ~0, which includes a plurality of belts 82 moving con-stantly on rollers ~3 from the chain bar outfeed conveyor ~2 to the conveyor trough 30, or ~rom left to right as shown in Figure 8. The strands 36 are maintained separated, and the belts 82 are travelling at a speed on the order o~ twenty to ~ifty ~eet a minute. Although the 2 ~2;~"~3`~ ~

g conveyor trough 30 is depicted in a general ~orm in Figure 8 as a wlg-wag conveyor, the preferred ~orm thereo~ is a wig-wag chute.
The chute form is shown in Flgure 4 with its two dotted line positions.
The chute 30 consists o~ ~hin sheets Or metal with a thin plastic ~ov-ering and a flexible plastic hinge at the top edBe. Skinny light arms move the chute back and ~orth. Thus, a chute embodiment advanta-geously weighs less than a tenth o~ what an equivalent conveyor embodiment would weigh.
The 06cillating tables ~Oa, 80b, 80~, 80d o~ the Sour ~eeds 22, 24, 26, 28 respectlvely, are physically secured together and mounted on a common long carriage 84 as shown in Figures 5 and 6. This ca~
riage 84 in turn runs on a set o~ wheels 86 on a track 88 therebeneath;
the sma~l wheels 88 ~apture the carriage 84 on the track 88 to ensure that it is not bumped of ~ the track. The carriage 84 together with the ~our tables secured thereon are driven back and ~orth by a single-cable driven drive drum system shown generally at 90. This system includes a cable 91 trained around a single one-ha~ turn idler drum ~2 and a multi-turn cable wrap driven drum 94, driven by a ~our-quadrant DC motor g6 which a~ows the drum to accelerate and decel-erate in both dlre~tions. The oscillating tables 80a, 80b, 80c and 80d are then moved back and forth on the track 88 along a path parallel to that o~ the conveyor trough 30. These transverse and longitudinal motions o~ an individual Gscillatlng table provide a zig-2ag deposit pattern of the elongate strands on the wig-wag conveyor trough 30, as described generally in the 1544, ~799 and 1232 patents. Each o~ the layup heads or feeds depo~its the strands 36 essentially individually on the conveyor trough ln this zig-zag path and generally over a length of the trough tha~ is at least as long as about one-and-a ha~ times the length o~ the elongate members or strands and is at least as long about thirty times the ~inal thickness d the compressed, composite product, æ taught ~or example in the 1544 patent.
This single cable drive drum system 90 provides a single drive point for all four tables 80a, ~Ob, 80c and 80d. Other drive systems (not shown) are also within the scope o~ thls invention including hydrauli~powered sys~ems and rack and pinion assemblies driven by 2~2~

reversib~e DC drive motors. The tables are moving about two to four times as fast along the track as their belts move the strands 36 across itse~. These motions are coordinated with DC drives to carefully define the point where the strands 36 drop off the tables 80 onto the conveyor trough 3û, to maximally spread the strands out on the trough. The strands 36 drop off the tables 80 at the end of the tables~
travel, and the coordlnated motion ensures that the strands do not drop o~r too early or too late, that is, before or after ~he tables 80 have reached the ends o~ their travel. This coordinated motion ensures an even interlacing o~ the strands from layup feed to layup feed. The present system shows the use of four layup heads or feeds 22, 24, 26, 28, which thereby define three interlacing points, but other numbers o~ layup heads can be used. For example, when three are used, there would be two interlacing points, and so forth.
There is a net root mean square benefit in averaging the strand deposits of ~our layup6, because ii there is a small dsnsity variation in one of the tables 80, it is only on~quarter density variation of the entire mat 32. Thus, the probability of having two, three or four of the layup tables 80 receiving (and delivering) low density, low mass flow at the same place in the layup is negligible.
Each layup head 22, 24, 2~, 28 therefore has a ma~s contribu~
tion to the mat 32 on the trough 30 as shown in Figure 9, wherein the contributions of the first, second, third, and fourth layup heads are shown respectively by 100, 102, 104 and 106. Each of the distances 108 represents eight-and-a-ha~ feet ~or example, and distances 110 are nineteen feet. Thus, a total distance of one hundred and eighteen and a ha~ feet is shown by reference numeral 112.
Each of the layups is ~ormed simultaneously such that the top or the bottom layers is being iorme~ at the same time as the ~ottom the top layers. That is, iS the boetom layer is being formed over a distance Y and the top layer is being formed over a distance Y~, Y and Y~ overlap one l~effective strand length,~ which is defined as the width of the conveyor ~eeding the oscillating tables that is ef~ectively cov~
ered by strands. By simultaneously forming each of the layups, angled layup bases (see Figure 11) are ereated on which the strands fall, and ~; ~

;5 ~:

these bases are consistent and angled across their entire interl'aces.
L~ the layup actions do not interact this way, the strands l'rom the start of the second layup head lie flat along the top of the first formed mat, and when compressive forces are later applied tend to flatten the strand angle ol~ the ad~acent strands below it.
Strand angle misalignment is improved about one-half degree be~cween the interfa~es, and consistent strand angles are thereby deiined. Although the small strand anE~le change may not have large benefits in strength properties of sections, signil'icant effect on dimensional stability especially during rnoisture recy~ling of the prod-uct will result. As an example, a 0.001 percent elongation of one side of a three and~ne-half inch wide, sixty-six i'oot long beam will pro-duce a five inch bow in the product. The one-hall' degree strand angle di~'2'elence can easily produce this effect.
Il' the layups are not interlaced then there will be on average a slightly ~etter angle. This is only because some parts of the layups have a zero degree angle and the other parts oi the layup have a on~half degree angle, and the one-half' deg~ree angle is constant after a certain travel ol' the four layup feeds 22, 24, 26, 28. By interlacing the l'our head~ there are no longer the intermediate areas between layups on the trough where the strand angle goes from one-half to zero deg~ree~, and these intermediate areas present dimensional stabil-ity problems in the final product. They could also have some el'fect on mechanical properties and bending because physical properties of the material can change slightly and because dimensional stability of the product a~ects the stability and therefore ef~ective load capacity of the product in service.
In Figure 9, the contributions of mass to the trough 30 during a continuou~ layup pro~ess are illustrated, and the overlapping con~ribu-tions of the first, second, third, and fourth layup heads are shown by reference numerals 100, 102, 104 and 106, respectively. The density thus in the last inch of the layup is appro~dmately zero, and the den-sity eight feet from there is approximately the full density contrib-u~ed by that layup head. It is a linear gradation of material mass flow rate off the table in the first and last eight feet.

~ ~ 6~ 0 ~

The mass deposition rate in pare determines the strand angle, and it is desirable to have the strand angle constant from top to bot-tcm of the layup. I- it is not, then slightly different mechanical pro~
erties as a function of a depth of the layup result. Thus, the present system allows a constant strand angle to be kept from a multiple sources of veneer.
Reierring to Figure 11, the contribution of the tirst layup is shown by 130, the transitional strand angle Or on~haLI to zero degrees is shown by 132, the second layup contribution is shown at 134, the cor~stant strand angle transition between the first and second layups is shown at 136, the third layup contribution is 138, the constant transi-tion strand angle is 140, the iourth layup is 142, the transition con-stant strand angle between the third and fourth layups is 144, and the top transition strand on~ha~ to zero angle is 146. The total product thickness o~ 11.4 inches is shown by dimension 148, and the depth of the produet having a constant strand angle oI on~hal~ degree is shown at 150.
From the foregoing detailed description, it will be evident that there are a number o~ changes, adaptations and modifications of the present invention which come within the province of th~se slcilled in the art. However, it is intended that all such variations not departing from the spirit o~ the invention be considered as withln the scope thersof as limited solely by the claims appended hereto.

, i .~ . . ~ .
.,

Claims (25)

1. A layup system comprising:
a moving carrier;
first layup forming means for forming a first strand layup on said moving carrier;
second layup forming means for forming a second strand layup on said moving carrier, said second strand layup interfacing with said first strand layup; and coordinating means for coordinating said first and sec-ond layup forming means such that the mat formed by said first and second strand layups has a continuous average strand angle at the interface between said first and second strand layups.

2. The layup system of claim 1 wherein said first layup forming means includes a first layup table from which strands flow onto said moving carrier to form the first strand layup and first con-veying means for conveying the strands to said first layup table, and said second layup forming means includes a second layup table from which strands flow onto said moving carrier to form the second strand layup and second conveying means for conveying the strands to said second layup table.

3. The layup system of claim 2 wherein said first and sec-ond layup tables continuously convey the strands from said first and second conveying means, respectively, to said moving conveyor to form the mat.

4. The layup system of claim 3 wherein said coordinating means drives said first and second layup tables together back and forth during the forming of said first and second strand layups along a path parallel to said moving carrier.

5. The layup system of claim 4 wherein said coordinating means includes a track and cable pulley means for driving said first and second layup tables on said track.

6. The layup system of claim 4 wherein said coordinating means drives said first and second layup tables along the path and relative to said first and second conveying means.

7. The layup system of claim 6 wherein said first and sec-ond layup tables travel along their path in a time generally equal to their strand conveying time across said first and second layup tables.

8. The layup system of claim 6 wherein said coordinating means drives said first and second layup tables to travel along the path at a near constant rate which maximally spreads out the con-veyed strands along said moving carrier in said first and second strand layups.

9. The layup system of claim 2 wherein said coordinating means causes said first and second layup tables to oscillate relative to said moving carrier.

10. The layup system of claim 2 wherein said first and sec-ond conveying means convey the strands at an angle of about thirty degrees to said first and second conveying means, respectively, but with the strands parallel to the motion of said layup tables along their tracks.

11. The layup system of claim 1 wherein said moving carrier includes a moving belt and belt sides to thereby form a trough, down into which said first and second layup forming means deposit the strands to form the mat.

12. A layup system comprising:
a moving carrier;
a first dspositing means for depositing elongate members on said moving carrier and thereby forming a bottom mat layer having a top surface; and second depositing means for depositing elongate mem-bers oh said moving carrier and thereby forming a top mat layer hav-ing a bottom surface wherein said bottom surface is formed at the same time; as said top surface and such that the average angle of the elongate members is substantially continuous throughout the interface of said top and bottom surfaces.

13. A layup system comprising:
a longitudinal wig-wag layup conveyor;
first and second strand layup sources;

first forming means for forming a first strand layup, with strands from said first strand layup source, on said longitudinal wig-wag layup conveyor; and second forming means for forming, with strands from said second strand layup source, a second strand layup on said longitu-dinal wig-wag layup conveyor, wherein said second strand layup over-laps on said first strand layup an effective strand length to thereby minimize strand misalignment inconsistencies at the interface between said first and second strand layups.

14. The layup system of claim 13 further comprising con-veyor means for conveying strands generally laterally from the first strand source to said first forming means, and said effective strand length being generally the width of said conveyor means.

15. The layup system of claim 13 wherein said first forming means forms the first strand layup in a zig-zag pattern on said longi-tudinal wig-wag layup conveyor.

16. A strand layup process, comprising the steps of:
forming a first strand layup on a longitudinally moving conveyor; and forming a second strand layup on the longitudinally mov-ing conveyor and generally on and interfacing with the first strand layup such that the strand alignment is substantially consistent across the interface of the first and second strand layups.

17. The process of claim 16 wherein said forming steps are substantially simultaneous.

18. The process of claim 16 wherein said first strand layup forming step is from a first strand source and said second strand layup forming step is from a second strand source spaced from the first strand source.

19. The process of claim 18 wherein said forming steps include continuously forming, from the first and second strand sources, at least in part a multi-layer strand layup on the longitudi-nally moving conveyor.

20. The process of claim 19 further comprising forming third and fourth strand layups from third and fourth strand sources such that the first, second, third and fourth layups interlace to form the multi-layer strand layup.

21. The process of claim 19 further comprising conveying the multi-layer strand layup to a layup press.

22. The process of claim 18 wherein said first strand layup forming step includes forming the first strand layup in a zig-zag pat-tern on the longitudinally moving conveyor.

23. The process of claim 18 wherein said first strand layup forming step includes depositing the individual strands from the first strand source effectively one at a time on the longitudinally moving conveyor.

24. The process of claim 23 wherein said first strand layup forming step includes depositing the strands from the first strand source on the longitudinally moving conveyor over a length of the carrier that is at least as long as one and a half times the length of the strands.

25. The process of claim 18 further comprising, before said forming steps, coating the strands from the first and second strand sources with at least one resin adhesive.