CA1063747A

CA1063747A - Blade of hockey stick and other composite reinforced structure

Info

Publication number: CA1063747A
Application number: CA233,263A
Authority: CA
Inventors: Marcel Goupil; Marc Ruel; Joseph D.L. Tessier
Original assignee: Individual
Current assignee: Individual
Priority date: 1975-07-30
Filing date: 1975-07-30
Publication date: 1979-10-02
Also published as: FI762135A; SE7608086L

Abstract

ABSTRACT OF THE DISCLOSURE
A non-wooden blade of hockey stick which is particularly adapted to at least match the advantages of the wooden blade of the hockey stick now used by the professional hockey player, in particular the resilience, impact resistance and relative weight or density. This non-wooden blade is characterized by a core of a syntactic foam composition which is particularly suited to produce a blade and a hockey stick having the desired characteristics and which forms a blade in cooperation with a pair of outer fiberglass laminations having a majority of fibers extending lengthwise of the blade. This core is made of thermoset polyester or epoxy resin with hollow microspheres of phenolic plastic or glass, and with short independent fibers of polyester, poly-amide or fiberglass. Preferably, a monofilament is wound around the outer laminations to positively prevent separation of the latter from the core. Also, an adhesion promoter is preferably added to the resin to improve the adherence of the resin to the microspheres.

Description

I`h~s i~-ventlon relates to a co~posite reinforcad structure and, more p~rtLcularly, to a blade of hockey stic~,which blade is of the typ~ ~1e o~ such col~osite rein~orc~d structur~.
It may be useful to point out that the professlon~lism 1n s30rt and, in ~articular, in hocXey, calls for ~ore sophisticated eql1iDment ~herein ths shape, di~ensions, weight, ~ro~o~tions and dynamic characteristics ~ust be strictly consid~red and abided by to rnanufact~s a successful product. The professional hoclcey ~laycrs, For instance, have become very selective for the hockey stick they will ~lay with~ and this i~nose~
stringent requirements on the ~anufacture of hockey sticks. For instance, the blade of a hoclsey stick ~ust conciliate o~Posing characteristics suoh as weiaht and resistance with lateral thickness and resilience. For exampleg now the professional hockey stick, as a whole, weighs some 63~
gra~s or 22 ounces and has a ~ooden blada which weighs some 120 ~rams or 4.25 ounces, which has a lower edge that must be as thin a~ poqsibls and -~-currently is only 0 370 inch thick snd has 8 lateral curve o~ up to one-half inch.
~p to the last decade or 90~ the hockey sticks were tr~ditionally made o~ selected woods. In recent years, there h~lve been propossd s4d ~atented di~ferent alternatives to the traditional hockey stick, either to supplement the attributes of the traditionally used woods or to shift to the use of lower grade woods.
In particalar, it has ~revlolsly been ~roposed to make at least part of a hockey stick o~ some ~lastic and to use Yiberglass to provide the necessary rein~orce~ent and resilience. However, in all pr~vious attemnts to improve and update the construct~on of a hockey ;~
stick, apparently, in~s~fficient consideration has been given to the blade per se and, in particular, to the weight o~ the blade ln itself and in relation to the weight of the handle or to the tot~l wei~ht o~ the hockey stick.
The anterior hockey sticks which h~ve been made with a non-wooden blade have not satis~ied the a~ore-~entionsd require}nents and~
therefore, have not been acceoted by the professional ~laysrs. Bes~deæ, - - 2 ~

such non-wooden blade produces an tunusual metallic ~ound impact ~hich i~ r~sented by the player~.
Other sport equip~ents ha~e requiraments ~hich are ~l~ilar to those o~ a hockey stick ~nd which, there~orQ, ¢an be met by ~he ~a~e material3 as thosa found ~uitable ~or the hockey stic~
It is a general ob~ect of the pre~t inYen~io~ to ~ a blade of hockey stick of a non-~ooden material a~d to form a he¢kcy stlck with such blade~ which ~inds acceptance by the professional hook~
playors.
It i3 a~other genersl obje¢t of the present in~ention to ~k~
blade of hockey stick which meets the afore-~entio~ed require~e~t~ a~d charaoteristics o~ a wood0n blade a~ now ussd by the pro~e~sional play~r~O
It is a more speci~ic ob~ect o~ ths present lnve~tion to pro~ide a blade of the above type ~hich ~vorably co~pete~ Hith the con~
tional wooden blade~ in particul3r ~ith regard to ~mpact resistano~
relat~vs weight or dens~ty~ wesr re~i~tance~ re~ilience and ~bich i~
relatively ea~ier to manufacture particularl~ ln vie~ of the r~quired latersl curvature.
It i~ ~nother ob~ect o~ the present in~ent~on to pro~ida a moldable core ~hich i8 psrticularly sui~ed to for~ a blad0 o~ ho~y ;~
stick in cooper~tion with a ~iberglas3 ~hell and, ~n other ~Qrd3~ whioh .
allow~ to meet the aPore-mentioned requirements o~ the prote3sio~sl hook~
stick. ~'~
It i~ a~other ob~ect of the pres~nt invention to pr~d~ce a blade o~ hockey stio~ uhich does not produce a re~ented me~allio 80und : upon impact.
It is still another ob~ect o~ the present i~ventio~ to produce a blade o~ hockey stick which include3 fib~rglas3 r0i~0rca~e~t ~;
arraneed to a~oid un~ecess~ry fiber~ and weights by u~ing a ~ib~r~las3 fRbrlc with a ma~ority o~ f~bers extended ~er~h~ise of the blad~
The above ~d other ob~eats and ~dvanta~o~ of the pre3~t inve~tion will be better understood wi~h the fo}lowing d3tailed descrlptlon or a preferred a~bodiment there~ ~hich i~ illustrated, by ., ............. ............................................................................. .....
:: ~ . . . . .. . : -way of sxample, i~ the accompanyl~g dra~iDg8~ wherein~
Fi2ure 1 i8 a lon~it~din~l ~ectic,n through a bl~de o~ hocko~
~tick m~de according to the prasent invention~
F~gura 2 i~ a p~rspectlve vie~ of' the blade o~ Figure 1 with oppo~lte lateral faeos partially p~eled o~f to show tho core of the blade; a~d Figure 3 i8 a cross-3ectional vi~w taken tr~ sversoly o~ the blade a3 saen along lln~ 3-3 in Figure 2. :: .
The illuætrated blado o~ hock~y ~ti~k inoludes a core 1 ~hich 10 i8 molded with the outline of a convsntional blade u3ing R æy~tactic .
~oam co~pos~tion made 0~ a th~ t~ing pol~ro3t~ hort ind~pende~t f~b~rs of polyester and hollow gl~æ~ ~lcroQpb6re~
: The cor0 i~ rein~orcad at th~ hoel portion, the tip ,: , portloll, tha bottc3l~ edge and the top edge by a stri~g of non-porous : ~ .
:,.- ~; .
tharmoeet or plastic poly~ster e~cter~ ,g aroulld tho blade a~d deri~ng a heel reinforcemen~ 2, a tip rainforce~e~t 3, a bottom rein~orc~nent 4 and a top reinf~rceme~t 5~ !i''- .~' ' ': `. ,, ~ she:Ll is prorided to l~ter~lly cor~ine ~e core 1, ~i~
she~l include3 ~ pair o~aces 6 of fiber~las3 fsbrir ~ red sgain~t dt 20 the oppo3~te lateral sides o~ the corc 1. ~he fibergl~ss ~bric is wo~en ~it~ at le~lst ~ait of tha rib~rs i~ one directio~ a~d posi~io~od . .
such that this 80~ or ~ore oi the ~ extends longitu~nally o~ the blads. Thi~ i~ sho~ in Figur~ 2 b~ tha fiber~ 7 ~hich constltut~
at least 80~t of th0 ~sbric ~d erte~d 1~3~thwi8~ 0~ the blad~ ~hils the fibers 8 constitute le88 than 20% o~ th~ ~abric a~d e~t~nd subst~n-tiall~ upright.
The core 1 i8 ~orm~d with a handlo Rnd g h~viDg a handle receivi~g cavit~ 10 e~tending downwardly and ~or~ardly 0108~ to the bottom edg~ of the core, at tho he~l portion of the latt~r. ~ small :; :-30 passage 11 i~ form0d through tha core i~ communicatio~ ~ith the boctQm of ~ B ~ 4 _ ~
~

.: , ~ : . ~ .:;:. .... , ,. .. , :

the cavity 10.
The core 1 may be ~ad~ with f;:ber~ of polyester, polyunlde ~;- `'"" ' ' '` ';~ ' '" .

-' and/or fiberglsss and with hollow mlcroJph~rss o~ ph~nollc pls~tic andJor glas~,.
The blade i9 ~ormed by c~pres,~ion ~oldl~, na~e~ b~
pressing together two-half molds ~illed ~ith the ~aterials~ On~ or mor~
layers oP ~ibergla3~ f~bric o~ the aeo~e~entioned ~pe aro laid i~ ono o~
tha two-hal~ ~olds, suoh that most of the fibers wlll extend leng~h~le~ o~
the blade. These layers may be previous:Ly wetted with the resing althollgh thi~ ha~ not been Iound to be necsssary. ;:
Tn B particular ~mbod~ment of this in~e3tion~ a ribbQ~ of polY- ~`
ester resin in a g~l ~orm i9 laid on the fibergl~ss rsbrie axound the ~riphery o~ the cavity in o~e-hslf moldg to form the heel, tip, bottom edge and top edge rain~orca~ent~ 2, ~, 4, and ~ ras~eoti~ely. This rlbbcn i9 not es~ential.
T~le aPor3-men~loned core oomposition ~n vlscous sta~e i~ lald o~
top of the rabric and a metal insert i3 positioned ln th~ ~old to ~or~
eavity 10. Then, one or more layer~ of ~ibergla3s rsbric ar~ lald o~ top ~ -o~ the ~ore conpo3ition. After clo~ing the mold and A~ter cur~ a~ 130&
. ., ~
for a~out ten minutes st ~ ~olding pre99ur8 0~ bet~eQ~ 500 and 800 po~
and preferably about 500 p~8~io~ the mold i~ op~ned and the solidified blade i~ trimm~d~ if neces~ary.
Th~ hQndl~ 12 of the hockey st~ck is secured by any ~ltsble adhe~i~e in the ca~ity 10. The oriric~ llow8 e8~ape Qf ~nr 3XC
adhesivs from the bottom o~ the handle reoeiYi~g c~rlt~ 10. ~ high teD~ile ~trength gla~s fib~r yarn 13 may be ~ound either only arou~d the ~o~nt b~_ tween the handle ~nd the blado an~/or around thls Jolnt and al30 the ~ull length o~ the blsde to pr~vent d~lamiDstio~9 i~ ~o desirsd. ~o~e~er3 thi~
h3J been f~und to be unnecass 9 .
- Acoording to ~ pre~erred ~mbodiw~nt, the face~ 6 are pre~erably made of a ~ibergla3s ~abric h~v~ng at least 90% Q~ the ~ibers 7 0~ending longitudinaIly o~ the blade.
The best results have bee~ obt~iD3d ~ith tha follo~inb~ ltatio~

the ~hort~ i~dapo~dent poly~ster ~iber~ rep~oseDt bet~oen 0.5 ~nd 10~ of the cora by volu~s;

tha hollow microspheres co~tribute Rt l~ast 50~ of tha void spsces of the core; and st lea~t 8a~ of bhe fiberglas~ fibers axt~nds longltudinally of th~ blade.
The blade made according to the present invantion typically weighs about 117 grams, a~q compared to 121 grams for the con~entiollsl wooden bl~de.
The blade o~ the presant invention is aasily and cheaply molded and may have a pr~selected lateral ri~idity by mere adjustm~n~ of the length of one layer of fiberglass fsbric.
The use of a ms~ority Qf longitudinally extenoir~ fib~rglas~
fibers allows to reduca the Weight Or thc blade by as much a3 20~ without reducing the resistance o~ the blade.
The short fiber~ used in the core endror the wove~ lay~rs definiag the shell of the composite structure ~r lamiDate may be ~sde o~ high t~n-sile ~trength ~ibers other than polyester f~bers. However~ th~y ~u~t hsve a comp~rable percent olongation and no brittlen~s~ to i~part to tho core the dasired impact rs~istance. For inst~aco, polyamld~ ~iber~ -or aramide fiber , such as tho~e kno~n under the registered trada mark "KEVLAR", ownad by 9uPont o~ Canad~ ~td., can bs used. The following are ~ .
pre~erred and non-limltati~e o~mples af the core compo3ition.
~X~NFI~ I
~ by wei~ht polyester r~si~ 8C~
bonzoyl psroxide (catalyYt) 2 organo silane 03t~r (coupli~g ~gant to pro~ote adhesion e~ the re~i~ to the microsph~res~ 1%
polyester fibers of betwe~ 0 1 aDd 0O5~ lo~g c^~ -microsph~r3~ mado o~ glaB8 and Or 75 microD~ in ;~
averags di~eter ~nd ~varago ~atl thickD~s~ o~ 1.5 micron (supplied und~r the regist~red trade mark "Eccosphsre~ typo I~25~ owned by ~er~an by weight Cuming Inc. _ :L00 E~AMPLF~
Pol~ester rasin formulatlon (including resin, oatalgst and coupling agent) 8C~
polyesker fibers as in Ex. I 8~
microspheras as in Ex. I 12X
lO(F~ot '' . -.
E ~LE III
Polyester resin formulation 80 polyester fiber~ 89 in Ex. I 7%
microspheres a~ in Ex. I 9 macro~pheres made of epoxg resln and of a d~meter range of 0.07 to 0.15 ln~h kno~n under ~ .
type EP-100 and abo~e~
mentioned registered trade mark "Eccosphere~ _____________ 100~ '' EXA~IE I~ :
Polyester re~in formulation 70 polyester ~ibers as ln Ex. I lC~
micro~phere~ as in E~. I 2C~

~ V
Polye~ter resin formulation65%
polye~ter fibers a~ in Ex. 1 7%
microsph~re~ a8 i~ E~. I 2 100~
Further core eompositions ha~e also been prepared and tested in ~hich the polyester resin compositions o~ the abo~ ex~mples replaced by a~ 0po~y resin formulation and the microapheres ~ere m~de of phenollc resin inste~d o~ gl~
It ha3 be~n ~ound that the pre~erred % rBnge3 ae tho i2BrsdieD~
of the cora composition ara as follow9:
resin 60% - 93% by ~ei~t short fiber~ 2~ - 15~,~ by ~eight spheres 5P _ 25~
The lA~i~stes obtainad in accordance with t~le inventio~ ha~e been found to be at lea~t f~ur times more resi~tant to ~mpact thsu kno~n la~n~te8 of eg~l weight and rigidity. ~.
By vsrying the peroentsge weight of the sh~rt ~lbar~ ~a th~ ooro ~ron zero to 15~, lt has been ~ound that I~d lmpact te~t~ glve ~lu~s increa~ing fro~ zero to 5.8 ~t lb~/inch. .
By increaslng tha loading of ~crosph~res ~r 18% to 3~ h~
resulting d~creasa i~ den~lty was about 10~ and there ~as 8ub8t~ntially ~0 change in the I~od impact strenæth and the rle~ural ~odulu8~
Thu9~ by u8ing the core of the iD~ention9 it has been ~ouoa : ~ :
tha~ a hookey blade i8 o~tained, ~hich i8 0~ a quality snp~rior to blado~
mad~ o~ th~ be~t grado wood as to welght, stiff~ess ~nd iMp~Ct re~i3t3~¢e, nnd is si~pler and les~ expensiv~ to ma~u*~cture and has unifor~ cha~a¢-teri8tic8 contrary to ~ood. Comparatl~e i~pact te3t8 u8ing a pucl~-likc ~eight dropped O~l the c~lter of th~ blade 3uppor~d at both e~ds, ha~e sho~n that the blade~ of the inve~atioIl regularlg resiYt to an i~p80t 0~ 3 ~t/lb~, whereas mo3t doodon blsde~ reln~roed ~ith ~iber~ sbrie bre~
under an impaot Or 25 to 30 ft/lbs.
A blado o~ the in~entioll ~eigh~ ~bout 113 grs~s~ oomp~red t~
120 gra~3 for ~ lloode~ blade Or the 8aiQ3 8i8e. `~
The sfore-descri~ad ca~po~ite r~inforced 3t~uct7lre, i~olud~g the shell and the core or the l~tter alo~e, D~ be u~ed ~ith ad~ntag~
to for~ oth6r sport ~gulpme~t3~ BU~h a~ o~rs~ paddles, ~kis~ et~ ~
~ EXAMP~E ~I -: A hookey blsd0 has been mad~ ~8 ~ollow~:
Fibergla3~ rosing~ made by B~y ~ Ltd. und~r eodo Nv.

..... . . . . . . . . .

,l~t`j~ 7 352-380b60c2 of 13 ounc~9 per ~quare yard~ ~J cut a~ rollow8:
B ) 2 nieces ~ 3~ x 12"
b) 2 pieces oP 2" x 8 c) 1 piece of 1~" x 4 one plece c), o~e piece b) ~nd one piece ~) w0re laid 1~ the bottom b~lf 0~ B mold in suparposed relationship with piece c~ laid from the bl~d~
~ ~ .
heel towards the hanole. The ln3ert for ¢avity 10 w~ positlo~ed 3na th~
resin compoqition iu properly meaaured ~nount ~9 poured o~er th~ roYingsO
Then, the second piece~ b) and a) ware laid i~ supQrposed r01~tion o~cr tbo resin The top hal~ o~ the mold ~as clo~ed. Th~ composi~ion ~as hoat~
A ~ c for about 10 minutes to cure the re3iu a~d the c~red blads w removed fr~n the ~old. The ~olding prcsqure ~as about 500 p.8~
The cured blQd~ w~lghed 131 gram~ an~ a~ter triEm~ng o~ i~s perlmeter, it weighed 105 gram~c ;;
The ~lbergla~s rovings ware cavered by the re~in ¢a~po9itio~ ~t sll ~aces of the blade.
The resin co~positio~ us3d was a~ rollo~

by woight :

62.70g 80 parts of (rigid) polyester resi~ (Raichold Polylite poly~s~er re~ . 338) ~ -15.67~ 20 part9 Rr (le99 rigid~ pol~e~t~r resin (Reichold Polylit0 ~o.
31~30) - :~
12.54~ lb parts o~ microQpheres ~Ecco~phRre" ty,pa I.~. 2 6067~ ~ p~rt~ ~P ~hort ~ibers~ high tanacity polye~ter ~bar-~ (6 denier3 p2r rila~e~ r tire cord grad~ sold ~ndsr registered trad~ mark ~D~C~0~ o~ DuPQ~t C~nad~ L~d~

0.7~% 1 part ~g~no 511a~8 ester (adh2~ion promoter) sold by UD1O~ Carblde C~DOEd~ L~mi~ed und~r cod~ A-174 ~ :

o~96% 1.1 part be~30yl peroxide (oat~lyst) sold und~r reg~st~red tr~d~ m~r~ nCADOX~, o~nsd by ~oury Ch~iG~
Corporatlo~ ~`

white p~g~ont 100~ 127.6 The u~o of t~o grade~ o~ polyester resi~ is ~5 ~d~ust th2 rigidity of the Pinal prodlct.
No filler other than the ~icro3pheres W88 U~qed.

7~
~o rainforoing ribbon to ~ake relnforc~m~nts 2, 3, 4, and 5 was u~ed, a3 the blade wa~ ~ound to have 3uffioien~ re~i~tance to br~ak-age at the edge~.
A woodan soft wood handle waY inserted ~ ca~it~ lO and adhere~
therai~ by ~e~ns o~ polyester resln.
A moldsd coating o~ polge~ter re~in ~ then applled onto both main face~ of the h~ndle, said reai~ beiDg rainforced wlth ,gla~8 fiber yarn eztending longltudinilly of the hsndle. Both the re~in ~d the ~Rrn e~tended over the heel portion o~ the pla~tle bl~de to ~hug ca~
resin directly o~er the already cast resin of the blade by u~ing ~ ~trsight ~old for receiving the handle and the heel vortion of the blade. To achie~e thiq, it was ~ound nece~qary to heat to 110C at lea~t th~ hsel ~ .
nortion of the blade contsining cavity 10 and inte~ded to be covered by the reqin of the hsndle. Coating of the ha~dle as above wa~ ~ad~
aocordance wi~h the method describod in Canadian Patent ~pplication Serial No. 207~171~ ~ilad Augu~t 16, 19749 inventor~ Marcel Goup~lg 5aston Ruel and Marc Ruel. -Thus, a unitary hoekey 3tick with a Yery qtrong ~oint bet~en the blade and the handle was obtained i~ 8 quick a~d ine~pensl~e ~anQsr but which had ~uperior qualit~es sa to ligh~ne~ ~ impact resi~tance ~d ;~
rlgidity, as compared to conventional ~iberglas~ ~abric raln~or~ed ~ood~
hookey ~ticks o~ good quali^~y.
Ano~her blade was m~de as abo~e but~ while 31ightly ch~glog ~h~
orlentation o~ the i~sart to form ca~itr 10~ a ~oode~ ha~dle ~as ths~
lD~erted ~n c~ity 10 and coated ~ abo~e d~scribed aDd ~urt~Qr by xold~og ;~
resin to the ~o narro~ races of the 8ti~k ~oi~ing with th~ blade 80 ao to obtain ~traight narrow ~sces longitudi~slly ~f the handle. Th~s9 i~
was ~ound pos~ible to obtain hockey ~ti~k~ ~n ~hich the angle bet~een the :~
bl~de and the h~ndle varie3 to suit indlvi~ual players' requlr3ment while U9iDg the aame mold~ for the blade aDd for ths ~tick.
R~vertlne to the compQsitlon of the blade core~ i~ ha~ been c ~
found that in the abo~e ~xa~pl~ the ~ ae hsd a density o~ o.8 aB
oompared to a den~ty of 1.23 whe~ no mlcrospheres are pro~t. Ih _ 10 --7 i ~

addition, the microspheres have bee~ found to 12lcrosse th0 impast r~8i~
ance o~ the blad~. This is undsrstandabls 3inca the mi~rwphera8 are 8~3- `~
~h~t ela3ti¢ and ~latten undsr ~mpact. Fill3rs other than microapher~
have bean te~ted and fowld to degrade tha ~echarlical propsrtics of t~e bladc.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1- A syntactic foam composition having high impact resistance, said composition comprising a substantially uniform mixture of polyester resin, short independent fibers and small diameter thin walled hollow glass spheres, the short fibers being selected from the group consist-ing of polyamide, aramide and polyester fibers and capable of appre-ciable elongation under stress, said fibers having a length varying between 0.1 and 0.5 inch, the thin walled hollow glass spheres having an average diameter of about 75 microns, the polyester resin being in an amount varying between 60% and 93%, the short fibers being in an amount varying between 2% and 15% and the hollow spheres being in an amount varying between 5% and 25% by weight of the total syntactic foam composition.

2- A composition as claimed in claim 1, wherein said glass spheres have an average wall thickness of about 1.5 micron.

3- A composition as claimed in claim 1 or 2, wherein said short fibers are polyester fibers.

4- A composite reinforced article having enhanced impact resistance comprising an elongated thin core having two opposite main faces and narrow edge faces, said core made of a syntactic foam com-position consisting of a mixture of polyester resin with short inde-pendent fibers and small diameter thin walled hollow glass spheres with the fibers and spheres substantially uniformly dispersed in the resin, the short fibers being selected from the group consisting of polyamide, aramide and polyester fibers and capable of appreciable elongation under stress, said fibers having a length varying between 0.1 and 0.5 inch, the thin walled hollow glass spheres having an average diameter of about 75 microns, the polyester resin being in an amount varying between 60% and 93%, the short fibers being in an amount varying between 2% and 15% and the hollow spheres being in an amount varying between 5% and 25% by weight of the total syntactic foam composition, and a reinforcing shell for said core including at least one layer of woven fiberglass fabric applied to and adhered to the opposite main faces of the core with at least 80% of the glass fiber of the woven fabric extending lengthwise of said elongated core, the polyester resin of the core serving to adhere the woven fabric to the core.

5- An article as claimed in claim 4, wherein said short fibers are polyester fibers.

6- An article as claimed in claim 4 or 5, wherein said glass spheres have an average wall thickness of about 1.5 micron.

7- An article as claimed in claim 4 or 5, constituting the blade of a hockey stick.

8- A composite reinforced article as claimed in claim 4, wherein said core and said shell form a blade of a hockey stick and said core is molded with a handle-receiving cavity, and further including an elongated wooden handle of rectangular cross-section fitted and adhered within said cavity at one end,molded coatings of thermoset resin adhered to at least both faces of said handle parallel to the blade faces, said coatings overlapping the face portions of said blade opposite said cavity and adhering to said polyester resin of said core, said molded coatings containing high tensile strength reinforcing fibers or monofilaments embedded therein and extending longitudinally of the handle.

9- A structure as claimed in claim 8, wherein the two remaining faces of said handle are covered by coatings of thermoset resin overlapping and adhering to the corresponding edge face portions of said blade oppo-site said cavity.