Hobbico Sturdy Birdy User manual

Sturdy
Birdy
INSTRUCTION BOOK
WARNING! THIS ISNOT A TOY!
Assembly and operation ofthis aircraft must bedone by orunder the direct
supervision ofa responsible adult. If not handled correctly, this model is capable of
inflicting serious bodily harm. It is your responsibility and yours alone to assemble this
model correctly, properly install all R/C components, and to test and operate it in a safe
and responsible manner.
Copyright 1994

TableofContents
Introduction............................................................................................................2
Parts List...............................................................................................................3
AdditionalItem Description................................................................................4
Additional Item List.............................................................................................4
Tools or Supplies Needed.....................................................................................5
Fin/RudderConstruction....................................................................................5
Stabilizer / Elevator Construction ........................................................................7
Wing Assembly ....................................................................................................8
Covering..................................................................................................................9
Installingthe Hinges ............................................................................................9
Attachingthe Control Horns ..............................................................................10
Fuselage Construction........................................................................................10
Final Assembly...................................................................................................16
Balancing.............................................................................................................. 17
GettingReady for Flying ...................................................................................17
Flying.................................................................................................................17
Repairing.............................................................................................................18
INTRODUCTION
Congratulationson yourpurchaseoftheHOBBICO STURDY BIRDY,THE FIRST REAL SUPER TRAINERYou
now owntheBEST FLYINGdurabletraineravailableBy followingthese instructionsas youassemble themodel you
willhavea great flyingplanethatwillnot onlyteach youhow to flybutitwillstickwithyou whileyou learn, no matter
how long itmay take!
The firstthingyou shoulddo afterreadingthisparagraph ischeckthe parts in this kit against the parts list on the next
page to makesure everythingis here
We stronglyrecommend thatyoujoinAMA,The Academy ofModel AeronauticsBeingan AMAmemberentitlesyou
to liabilityinsurance,putsyouintouchwithyourlocalflyingcluband includesa subscriptionto MODEL AVIATION
magazinewhichhas a monthlylistingof all"goings on" inmodel aviation
The insuranceis themost importantadvantageoftheAMAmembershipbecause ifyourmodel hitssomeone or
somethingyou are liablefor anydamageitcauses.
The address for theAMAis.Academy of Model Aeronautics
5151EastMemorialDrive
Muncie,IN47302
[phone]
We also recommend thatyou joinyourlocal flyingclubThere you willfindpeople who can help you learn to flyand
teach youthe safe waysof handling youraircraft.
2

PARTS LIST
Stock#..........Description ................................Qty
ARF1F01......Plastic FuseTube..........................1
ARF1F02......AluminumChannel ......................1
ARF1P01......InstructionBook...........................1
ARF1R05......1/64"Ply Fin Doubler..................1
EM2040 ........Engine Mount(Left & Right).......1
ARF1W02.....Plastic Wing Protector..................1
FWING01L...Molded Foam Wing- Left............1
FWING01R...Molded Foam Wing - Right..........1
L-6U..............Aluminum LandingGear..............1
PLTB009.......24"InnerPushrod........................2
PLTB011 .......24"Outer Tube .............................2
PLTB012.......12"InnerPushrod.........................1
PLTB013....... 12"Outer Tube.............................1
NYLON87 ....CA Hinge Strip .............................1
ARF1A01 .....Stab & Wing Sub-Pack
ARF1R04......Balsa Fin Doubler.........................1
ARF1S01 ......Stab Front .....................................1
ARF1S02 ......Stabilizer.......................................1
ARF1S03 ......Elevator.........................................1
ARF1W01 .....Birch WingJoiner..........................1
ARF1A02 .....Fin & Rudder Sub-Pack
ARF1R01......Fin Front.......................................1
ARF1R02......Shaped Fin....................................1
ARF1R03 ......Rudder .........................................1
ARF1A03 .....Small Wood PartsSub-Pack
ARF1F03 ......Firewall Doubler...........................1
ARF1F04 ......Firewall ........................................1
Stock#..........Description ................................Qty
ARF1F05 ......LandingGear Strips.....................2
ARF1S04 ......1/16" Ply Stab Doubler.................1
DOWEL030..1/4"Dowel....................................4
ARF1M01 ....Hardware Sub-Pack
NUTS001 ......4-40BlindNut..............................6
NUTS002......4-40 Hex Nut................................2
NUTS010......6-32 Hex Nut................................4
NUTS014......8-32 Hex Nut................................2
NYLON03 ....Control Horn.................................2
NYLON17....NylonClevis.................................3
NYLON52 ....5-1/2" NylonTie...........................2
SCRW002 .....2-56 x 5/8"Bolt............................4
SCRW010 .....#4x 5/8" Sheet Metal Screw .......4
SCRW024 .....#2 x 3/8"Sheet Metal Screw........8
SCRW055 .....6-32 x 1-1/2" Bolt.........................2
SCRW052 .....4-40 x 5/8"Bolt............................4
SCRW053 .....8-32 x 1/2"Bolt............................2
SCRW104 .....4-40x 1-1/4" Bolt.........................4
WBNT146.....Pre-bentTailskid...........................1
WIRES16......12" Threaded LinkRod................3
WIRES20......1" Threaded LinkRod..................3
WSHR002.....#4LockWasher............................2
WSHR004.....#6 Flat Washer...............................
WSHR005.....#4 Flat Washer..............................4
WSHR010.....#8 Lock Washer............................2
WSHR011.....#8 Flat Washer..............................1
3

ADDITIONAL ITEMS
NEEDED
Here is a description ofsome ofthe additionalitems
you willneed to assemble yourSTURDY BIRDY.
GLUES
C/A (Cyanoacrylate)glueswillbe used to gluethe
wood parts togetherbecause theyare strong and very
fastcuringDo not use C/A gluesfor anyofthewing
constructionbecause most C/A glueswillattackand
dissolvethefoamwingThey come indifferent
viscositiesThinC/Agluecan be used whengluingparts
witha good tightjointWhenusingthistypeofC/A,
assemble theparts firstand thenadd theglueItwill
penetratethejointand cureina coupleof seconds Thick
C/A gluehas a longercuringtimethatgivesyou more
timeto get theparts assembledaccuratelybefore the
gluecures and thethickerconsistencyhelpsfillpoor
fittingjointsC/A Acceleratorspraycanbe veryhandy
for speeding upthecuringprocess ofthethickC/As.
Epoxy is a twopart adhesive thathas to be mixed
before itwillcureWe willuse epoxy gluefor thewing
assembly since ittakesa littlelongerto cureand does
not attackfoam Epoxiescome inseveral differenttypes
withmanydifferentcuringtimesWe recommend Great
Planes Pro 30MinuteEpoxy (#GPMR6047).
ENGINE
The STURDYBIRDYis designed to fly witha
standard 20 size2-cycleengineThe OS20 FP is a
great,inexpensiveenginethatprovidesplentyofpower.
Thiscombinationisidealfortheaverage beginner.A
25- 30sizeenginecan be used if youwouldlike
snappierperformanceespeciallyat higherelevations
wheretheairis thinnerWe recommend thatyoudo not
use an enginelarger thana 30as theadditionalweight
makestheplanemore difficultto flyat slow speeds The
Great Planesadjustableenginemountprovidedwiththe
STURDY BIRDY willfitmost .20-.30engines.
RADIO
The STURDYBIRDYrequires3 channelsto flybut
there are not many3 channelradios produced anymore
Thereforeyouwillmore thanlikelyenduppurchasinga
4channelradio with3 or4 servos whichusuallycosts
less thanthethreechannelradios anywayYour next
planemayrequirefourchannelssince itwillprobably
haveaileronsThe radio system youpurchaseshould
have standardsizeservos sotheywillfitintothe
fuselagechannelMinior microservos willalso work
buttheywillrequiresome modificationsto fitproperly.
Large servos willnot work in the STURDY BIRDY.
FUEL TANK
The STURDY BIRDY was designed to hold a square
tankWe recommend a Great Planes 6 oz. tank
(#GPMQ4102).
COVERING
Althoughnotabsolutelynecessary, the "tail
feathers"andthewingshouldboth be covered witha
"low heat"typeiron-oncoveringTop FliteEconokote
is perfectforyourSTURDY BIRDY. The covering
willnotonlymakeyourplanelook nicer,butitwill
also add strength and make itlast longer.
HERE ISA HANDY LIST OF THE
ADDITIONAL ITEMS YOU WILL NEED.
1.20- .302-Stroke Engine
13-4ChannelRadiowithStandard Servos
2or3 9x4or 9x6Propellers
22-1/2" Wheels (Great Planes#GPMQ4223)
16 oz Tank (Great Planes #GPMQ4102)
1box #64RubberBands(Hobbico#HCAQ2020)
1/2oz.Thin CA (Great Planes #GPMR6001)
1/2oz.Thick CA- (Great Planes #GPMR6013)
130Mm. Epoxy (Great Planes #GPMR6047)
1rollLow Heat Iron-on Covering
(Top EliteEconokote)
11/4"Foam Rubber(Hobbico#HCAQ 1000)
112"MediumFuelTubing
(Great Planes #GPMQ4131)
TOOLSNEEDED FOR ASSEMBLY
Hand orElectricDrill
DrillBits(3/32",1/8":3/16":5/32",7/32")
SandingBlock or T-Bar Sander
SealingIron
Razor Saw
HobbyKnife
Pliers
Screwdrivers
T-Pins
Hammer
Waxed Paper
NylonReinforced StrappingTape
4

CONSTRUCTION
FIN/RUDDER
D1.The finis made upofthethree pieces shown above.
Locatethese three pieces and lay them out.
D2.Gluethefrontpart ofthe finto the mainpart using
thinC/A.Assemble thetwopartsandcheckto make
suretheyfitproperlyandthenapplya lineof C/A along
thejoint.Whenthegluehas cured,flipthepieces over
and add a littleglueto theother side.
sothattheouterhingesare approximately1"from the
ends ofthe rudderand themiddlehingeis inthe center.
D4.Draw a linedown themiddleof thetrailingedge of
the finandalso downthemiddleoftheleadingedge of
therudder.A sheet ofwood (or anything)1/8" thicklaid
down nextto thepiece makes iteasy to do this.Transfer
thehingelocatingmarks from the sideto the edges as
shown above.
D5.Use your hobby knifewitha #11 blade to cut the
hingeslots inboth thefinandtherudder. The slots
shouldgo straightintothebalsawithoutcomingout the
side and should be about 3/4"deep.
CAUTION!!!: Youmust useextremecarewhen
cutting hinge slots withan Xacto knife,to avoid
cutting yourself! If the balsa part breaks whileyou
arepushing on the knife,the blade could gointo your
hand before you know it! A goodprecaution is to
wear leather gloves whileperforming thisstep.
D3.Lay therudder inplace against thetrailingedge of
thefinand,usinga hinge(seestep 29,p. 9) as a
template, mark thehingelocations. They are spaced out
5

D6.Trial fitthe finandrudder together usingthe hinges
to check for proper alignment.Do not gluethehingesin
place yet!Sand therudderand/or finsotheymatch each
other at the top.
D7.Remove thehingesfrom therudder
and bevel theleadingedge withyour
sandingblock as shown inthesketch. This
isto allowtherudderto swingeither
direction once thehingesare gluedin.
D8.Add the 1/4"x 1/2"balsa doubler to each side of
the finas showninthephoto above. Use a razor saw to
cut the excess off at the leading and trailingedges.
D9.Check thefitof thefinassemblyintothealuminum
channel.Itwillmost likelybe a littleloose andwe want
anicetightfit.Add a stripof the1/64"plywooddoubler
to ONE side of thefingluingittothebalsadoubler.
Check thefitagainand ifitis stilla littleloose, add a
plywooddoublerto theotherside.Ifyou need to you can
sand theplywoodslightlyto helptheassemblyfit.Also,
youcanhavethecoveringmaterialcontinuedownover
thedoublersifyouneedtheadditionalthickness.
D10.Positionthefinassemblyinthechannelwiththe
trailingedge of thefinevenwiththe endof thechannel
and press itinplace.Markthelocationof thestabilizer
bolt holes on thebottom ofthefinand thenremove the
finfrom the channel.
D11.Wrap a piece ofmaskingtape arounda 7/32"drill
bitabout 1/2"from theend ofthebit.
D12.Drilltwoholes inthebottom of thefinassembly
to makea space for thestabilizerbolts.Be carefulnot to
drillanydeeper thanthemaskingtape or you may punch
throughtheside ofthefin.
6

D13.Use a sandingblock to roundtheedges ofthe
fin/rudderassemblyas shownabove. Givethesides a
quicksandingwithsome finesandpaper to get itready
for the covering.Thiscompletes thebasic assemblyof
thefinandrudder. The hingesandcontrol horn will be
installedaftereverythingis covered.
D16.Mark thehingelocationsusingthesame technique
you used instep #4. There are fivehingesused here. The
outerhingesare approximately1"fromtheedge. The
middlehingeis inthecenterandtheothertwohingesare
centered betweentheouterhingesandthemiddlehinge.
These hingelocationsare notcriticalbutproper
placementmakesiteasier to findtheslots aftertheparts
are covered.Cuttheslotsforthehingesand test fitthe
stabilizerand theelevatortogether to check forproper
alignment between the two parts.
STABILIZER
D14.The stabilizerand elevatorare assembled from
these threemainpieces. Locate these and let'sget started.
D15.Gluethefrontof thestabilizerto theback using
thinC/Ajustasyoudid for the fininstep #2.
D17.Use some thickC/A to gluethe1/16"plywood
doublerinplace on thestabilizer.Thissideisnow the
bottom of thestabilizer.Use a rulerto get thispiece
centeredas close as possible.Use adraftingtriangleor
carpenter'ssquare to drawa lineperpendicularto the
stabilizertrailingedge andthroughthecenterofthe
stabilizerto thepointwheretheleadingedges meet.
D18.Usea pencilanda rubberbandto holdthe
stabilizerinplace as showninthephoto. Sight down the

bottom ofthechanneland linethestabilizerupwiththe
channel(usingthelineyoujust drew)Whenyou are
satisfiedwiththealignmentdrawa linedownboth sides
ofthechannelon thetop ofthestabilizer.
D19.Removethepencilandrubberband andwiththe
stabilizercentered over thelines,drilltwo1/8"holes
throughthestabilizerusingtheholes inthechannelas a
guideThe trailingedge of thestabilizershouldbe
slightlypast theend of thechannel.
D20.Use a sandingblock withsome finesandpaper to
round off theleadingedges, trailingedge andthetipsas
youdidtorthefinandrudderAlso sand thetop and
bottom surfacessmooth This completesthebasic
assemblyof thestabilizerand elevatorThe control horn
and thehingeswillbe installedafterthetailis covered
slots inthewingto make sureitfitsnicelyMixup
about1/2 oz of epoxyandspreaditthroughoutthe
slotinone wingpanelWiththewingpanelupside
down,insertthejoiner inplaceandsqueezeoutallthe
excess epoxy sothatthejoinerisflushwiththebottom
ofthe wing(whichis facingup)Try touseenough
epoxysothattheslotiscompletelyfulland levelwith
thesurfacesof thewing
D23.Lay some waxedpaper downon theworksurface
and mixupanotherounceor soof epoxy Spread the
epoxy throughouttheslot andon theroot (middleend)
oftheother wingpanelSlidethetwowingpanels
together andlinethemupas close as possibleUse
several T-pinsand maskingtape to helpholdthemin
alignmentFlipthewingassemblyover sothatthe
bottom ofthewingsare facingupand make surethatthe
joineris seated properlyintheslot Wipe oft anyexcess
epoxy before itstarts to cureItis importantthatthe
wingsare joinedwithboth panels being accurately
alignedwitheach other.
WING ASSEMBLY
D21.Using a sanding block with some finegrit
sandpaper, (240-320 grit)removethelittlenubsand any
mold lineslefton thewingfromthemoldingprocess.
D22.Testfit the 1/8"plywood dihedral joiner in the
D24.Aftertheepoxy from thelaststep hasfullycured,
place thewingupsidedownon theedge of a tablesothat
only1/2 of thewing(fromone wingtipto the center
joint)is restingon thetableStartingat thewingtipthat
is restingon thetable,laya stripof nylonreinforced
strappingtapedownsothatitcrosses over thecenter
joint directly over the wing joiner Press the tape firmly
onto thewingand downintothefillet(wherethebottom
ofthewingmeets themountingplatform)andthenflip
the wingaroundand continuethestripof tape out to the
8

other wingtip.Apply two more strips oftape between
thisstripand thetrailingedge ofthe wingand thefourth
stripshouldbe added between thefirststripand the
leadingedge of thewingThe photo shows where the
strips shouldbe located. Try to get thistape stuckdown
as tightlyas possible because itadds a tremendous
amountofstrengthto thewingwhenproperlyapplied.
Make sure you do not change the washout(twist)or
dihedralofthewingwhenapplyingthetape stripsIf
youare planningon doingsome aerobatics or combat
withyourSTURDY BIRDY youshouldalso putthree
stripsof tape on the top surface ofthe wing.
INSTALLING THE HINGES
D28.Aftercovering thetailsurfaces, thehingescan be
installedUse yourhobby knifeto findtheslotsyoucut
earlierand make slitsinthecoveringsoyoucan pushthe
hingesintoplace and trialfitthe pieces togetheragain.
D29.Cut thesupplied2"x 9"CA HingeStripinto24
individual3/4"x 1"hingesand bevel thecorners as
shown inthesketch Installthecontrolsurfaces withthe
hinges centered inplace Make sure thesurface operates
smoothly Deflect thesurface allthewayinone
direction,thenapplyseveral drops ofthinCA onto the
center ofeach hingeThe CA willwickthroughoutthe
entirehingejointandintothewood Deflect thesurface
the other directionand gluethe same way. Flex the
surface to loosen it up.
D25.Trim theplasticcentersection protector to size by
usingeitherscissors or yourhobby knifeto cutalongthe
scribe linesUse some coarse gritsandpaperto scratch
uptheinnersurface of theprotector sothegluewill
adhere betterTestfitit on the wing and then use epoxy
to glueitinplace.
COVERING
D26.The tailsurfaces(fin,rudder,stabilizerand
elevator)shouldbe coveredwithone of theiron-on
coveringsto helpprotectthemfrombecomingfuel
soaked andruinedIfyouarealsogoingto coverthe
wing,whichwillhelpitlook nicerlonger(andadd a
smallamountof strength),you can save a littlemoney
by onlybuyingonerollof lowtemperaturecovering
(Top FliteEconokoteisrecommended)andusingitfor
boththewingand thetailsurfacesOtherwiseyou can
useanytypeof coveringforthetailsurfaces,but,
rememberto use a lowheatcoveringforthewingA
fewstripesor yourAMAnumbercan reallyadd to the
looks ofyourSTURDY BIRDY.
D27.Follow theinstructionsthatcome withthe
coveringandcoverthetailsurfacesat thistimeIt is a
good ideato coverthebottomsurfacesfirstto get
familiarwiththecoveringsincethesesurfaceswill
normallynotbe seen Whencoveringthewing,cover
rightoverthetapeandplasticwingprotector, justtry
to use as littleheat as possible.
ATTACHING CONTROL HORNS
D30.Position thenyloncontrolhorn on theleftside of
the rudderabout1"upfrom thebottom withthefour
holes linedupwiththeleadingedge. Use a drop ofThin
C/A to tack gluethehorn inplace.
9

D31.Drill two3/32"holes through the rudder using the
control hornas a guide.
roundoff thecorners witha
sandingblock. Test fitthedoubler
intothefrontoftheplastic
fuselagetubeas showninthe
photo. The firewalldoubler
shouldfitintothefuselagewitha
snugbutnot tightfit.The frontof
the fuselageis cutat a slightangle
sothefirewalland thustheengine
willpointdownslightly.Because
ofthisanglethetop andbottom
edges ofthe firewalldoublerare
also cutat a slightangle.Make
sure youinstallthefirewall
doublersoallofitssides match
upnicelywiththesides ofthe
fuselageas shown inthesketch.
D32.Securethehornto therudderwithtwo2-56 x
5/8"machinescrews. The screws shouldthreadinto
thenylon"nutplate"on theoppositesideof therudder.
Althoughnotnecessary,youmayusesome wire
cuttersor an abrasivecutoffwheelto cutthescrews
off evenwiththeplate.
D33.The other control horn should be installedon the
topsurfaceof theelevatorabout1"to therightof the
centerline.Followthesame procedurefor installing
thiscontrolhorn.
FUSELAGE
D35.The 3/8"plywood firewalldoubler is now glued to
the 1/4"plywoodfirewallfront.Use eitherThick C/A or
epoxyand makesurethatthefront of thefirewall
doubler is centeredon theback of thefirewall. Wipe
awayallexcess gluethatsqueezesout.
D36.Draw a verticalandhorizontalcenterlineon the
1/4"plywoodfirewall.Cuttheenginemounttemplate
fromtheback of thisbooklet and tack glueitto the
firewall,alignedwiththecenterlines.Drilla 1/8"bolt
hole at each ofthe marked locations.
D34.Locate the 3/8"plywood firewalldoubler and
10