build your first flying scale model

7/22/2019 Build Your First Flying Scale Model

1/178

Build your first flying scale model - Chapter 1 - Tools

you will need

One of the nice things about this hobby is that you don't actually need that

many tools to get started. Here are the essentials:

!

" sharp #nife

There are plenty of options here$ but my weapon of choice is a brass %wann

&orton #nife used with their ecellent scalpel blades. &ine is what they call

the (o.) handle. &y preferred blade type is the 1*"$ but other shapes are

a+ailable. The (o.11 blades are also rather good$ being somewhat more

slender and ,pointy,. These #ni+es and blades are a+ailable to buy in most

art shops. " cheaper alternati+e are those #ni+es with the retractable long

blades where you snap off the tip when it gets blunt to re+eal a new point.

ou get about 1 chances to change your tip before you ha+e to buy a new

one.

There is no point in trying to carry on with a blunt blade - the balsa can

crush or tear$ and it is simply not fun any more$ so ma#e sure you #eep some

spares in stoc#.


2/178

%teel rule

/ery useful for #eeping straight lines when cutting out balsa parts$ also for

stripping your own wood from sheet.

0ins

ou need these for holding the parts in place o+er the plan on the building

board. %pecial modellers pins are a+ailable with wide heads to hold parts

down securely$ but 2ust use standard plastic headed ones. The finer the

pins$ the less li#ely they are to split the wood if you push them through.

0liers

" pair of needle nosed pliers will be needed for any wire bending you ha+eto do - nothing fancy though$ and you will probably ha+e a pair in the house

somewhere anyway.

(eedle files

" set containing se+eral different shapes is a good in+estment - they are

handy for filing small openings$ such as holes for thrust buttons$ motor pegs

etc.

%andpaper34mery paper

One of the most useful tools you can ha+e can be pic#ed up cheaply in pac#s

of 1* at your local chemist or drug store. am tal#ing about emery boards$

which some people actually use for filing their fingernails. These are ideal

for general sanding wor# on model airframes$ especially as they ha+e a

coarse and a fine side. also #eep a some sheets of wet and dry paper handy

in )5* and 5** grit si6es - the 5** being good for final finishing.

7a6or saw

0erhaps not absolutely essential$ but you will find this a +ery useful tool

whene+er you ha+e to cut up a balsa bloc# 8not easy with a scalpel9. The

deeper the blade$ the thic#er bloc# of balsa you can tac#le. f you only use it


3/178

on balsa$ this could be a once-only purchase$ as the amount of times you use

it$ it should not get blunt.

Cutting mat

O$ you can get away without using one of these$ but it does sa+e the #itchen

table from damage$ and the one in the picture abo+e only cost me ;< from a

local mar#et stall. f you use an old piece of wood or something to cut on$ the

danger is that the #nife blade will tend to follow the grain of the wood rather

than the part outline you are trying to follow.

Building board

0lenty of possible options here. How big you go will depend on the the length

of the biggest model you are li#ely to build. &y trusty board consists of a

piece of fibreboard glued to an old chipboard shelf$ The fibreboard is softenough to push pins into easily$ and the shelf #eeps it flat. #now some

people use cor# floor tiles or noticeboards$ and others use ceiling tiles. Ha+e

a wander round your local = superstore and see what you can find.

"lternati+ely$ you can buy magnetic building boards$ complete with small

steel bloc#s to hold parts in place. ha+e ne+er tried one myself$but if you

clic# hereyou can read about >ohn 4rnst's eperience of using one.
http://www.smallflyingarts.com/Archives/Feature_Articles/Magnetic_board/magnetic_board.htmhttp://www.smallflyingarts.com/Archives/Feature_Articles/Magnetic_board/magnetic_board.htm


4/178

"dhesi+es.

Below is a picture of my current selection.

Ta#ing each type in turn:

? "liphatic wood glue. ou can see a couple of brands in the photo. This

water-based adhesi+e is what use for @*A of my airframe construction. t

is similar to the traditional white wood glue$ but does not dry rubbery$ so

you can sand it. t is usually tinted a yellowish shade by the manufacturers.

t is relati+ely slow drying$ gi+ing time to ad2ust 2oins$ and does not shrin#

li#e balsa cement$ so delicate structures are unli#ely to be distorted.

? Balsa cement. Traditional sol+ent based glue as used by generations of

balsa modellers. The smell when opening a tube still ta#es me bac# to my

early forays into the hobby when was about 1*. Humbrol and "mbroid are

two well-#nown brands. One ad+antage of balsa cement is its uic# drying

time$ which find useful when applying fuselage stringers$ for instance.

Often you only ha+e to hold the stringer in place for less than a minute$ and

it will stay there. 0re-gluing will strengthen a balsa cement 2oin


5/178

considerably$ especially when gluing end grain 8e.g. a fuselage cross

member9. >ust put a smear on the ends first and let it soa# into the wood.

hen it is dry$ apply a second coat and install the part. balsa cement is also

useful for attaching wire parts to balsa$ in con2unction with a thread

wrapping. 8peeling the glue off your fingers afterwards is part of the

pleasure9.

? Cyanoacrylate 8%uperglue9. (ow please remember that this is a personal

opinion$ but really hate this stuff$ and only use it when there is no

alternati+e. hyD ell$ the fumes are noious$ it is hea+y$ 2oins can be

brittle and it stic#s far more readily to your fingers than anything else. t

does ha+e its uses howe+er$ such as gluing in aluminium or brass tube

bushings$ attaching ply facings to balsa and of course urgent field repairs$ so

always #eep some to hand. The bottle shown features a brush applicator$

which find uite handy.

? 0acer Eormula 5* Canopy glue. would not be without a bottle of this

now$ as it is the best thing ha+e come across for attaching canopies -

basically it does what it says on the bottleF t loo#s li#e a normal white wood

glue$ and is water soluble$ but there must be some special additi+es in there$

because it stic#s li#e cra6y. t also dries completely clear$ so any residue is

+irtually in+isible. &ost good model shops should stoc# it$ as the 73C boys

use it for their canopies too.

? GHG general purpose adhesi+e. The big plus of the GHG glue in the

yellow tube is that you can use it to stic# paper fillets and panels onto your

airframes without causing them to swell 8with water-based adhesi+es9$ or

distort as they dry 8as can happen with balsa cement as it shrin#s9. The

disad+antage is that you tend to get a few strings here and there$ and the

glue always remains rubbery$ so there is no chance of sanding it.

? lue stic#. only use these +ery rarely when building my models$ but

many of my friends 8especially in the G%9 use them all the time. Their chief

use is to attach tissue to airframes$ and stic# cut-out paper or tissue

mar#ings onto the co+ered airframe. The adhesi+e can be reacti+ated using

a trim iron to ensure edges are firmly fied down. ou can also buy

restic#able glue stic#s$ which amongst other things can be used for stic#ing

paper patterns onto balsa before you cut them out 8apply the glue to the

paper$ and you should be left with no residue on the balsa9. "lso for

temporarily stic#ing pairs of balsa parts together$ so they can be sanded to

eactly the same shape.


6/178

(oious fluids

Below you can see my collection of doubtless etremely ha6ardous chemical

liuids.

n more detail:

? =ope. This is used to seal the tissue after it has been water-shrun#$ and

add a degree of waterproofing. There are se+eral types on the mar#et$ and it

is important to #now the differences. On the left there is standard nitrate

shrin#ing dope - similar to the Humbrol type ha+e used since the year dot.

t is getting harder to find now$ and wonder if it is only a matter of time

before the go+ernment stops letting modellers buy such nice smelling

products. tend to use nitrate shrin#ing dope now 2ust as an adhesi+e when

applying tissue - but you can read more about that later. n the centre isnon-shrin#ing nitrate dope which is what now usually finish my models

with$ thinned *3* with cellulose thinners. On the right is Butyrate dope$

which can be useful because it is less flammable than nitrate dope. This

could be an ad+antage for >ete or 7apier powered planes. t is not as stic#y

as nitrate dope$ so not as suitable for adhering tissue. t shrin#s less than

standard nitrate dope$ but understand it can carry on shrin#ing for longer.


7/178

? Thinners. Called Cellulose thinners in the G$ but probably 2ust dope

thinners e+erywhere else$ you ha+e to ha+e some of this to dilute your dope

with. The thinners are +ery +olatile$ and contain harmful chemicals$ so best

to use outdoors$ or at least in a well +entilated room. t is better to to get the

more epensi+e high grade +ersion if you can$ as this will be less prone to

gi+ing a ,bloom, on the tissue as it e+aporates. am told car restorationwor#shops are a good place to get hold of this stuff relati+ely cheaply - if you

buy from the model trade you tend to pay through the nose.

? rylon Crystal Clear. This is the finishing medium of choice o+er the

pond in the G%"$ especially in households where the rest of the family will

not tolerate the smell of dope. /ery con+enient to apply from the aerosol can

as well. Gnfortunately you cannot buy it in the G 8if you #now better$

please let me #nowF9. brought mine bac# from holiday with me. Crystal

Clear has an acrylic formulation$ so there may be something eui+alent o+er

here - if anyone has done any eperimenting$ would lo+e to hear from you.

? %anding sealer. This is basically dope with a mineral filler added$ and it is

used to prepare a bare balsa surface before final finishing. The powder will

help to fill the grain$ and after sanding$ a smooth surface will be obtained 8it

may ta#e se+eral coats9. f you cannot find it in the shops$ 2ust add some

talcum powder to normal dope.

7ight - rec#on that is enough to be going on with - any other stuff that

might be needed will be described if and when it comes up during the build.


8/178

Build your first flying scale model - Chapter < - etting

started

The first step will be to ma#e some home made printwood$ using a

photocopy of the part patterns you downloaded. f you cut parts sheet

) close around the top of the fin$ you will be able to match it up to

sheet


9/178

%till$ could be worth ha+ing a loo#$ 2ust in case they ha+e anything

decent in stoc#. tend to buy my wood from Elitehoo#$ who sell it out

the bac# of their +an at model shows around the country. They are

usually to be found at the Old arden model e+ents. "ll their wood

has the weight mar#ed on in grams$ which is +ery helpful when

comparing sheets.

"n alternati+e source$ which also use$ is the pac#s of 1


10/178

hold the balsa together and reduce the ris# of splitting along the grain.

"s you use each part$ peel the paper off first. f you find paper

residues are being left behind$ these can be remo+ed with lighter fluid

8apparently9.


11/178

0lace the photocopied pattern face down on the balsa sheet. Hold a

wad of #itchen roll o+er the open top of a tin of dope thinners and

turn it upside down briefly. ipe the #itchen roll uic#ly o+er the

bac# of the pattern until it all goes transparent$ and only then apply

some pressure using the drier areas of the wad. or# your way o+er

the whole pattern. f you flood too much thinners onto the paper$ thetoner will run and go blotchy. To see how you are doing$ lift up a

corner of the pattern and peel it bac#. f it loo#s fine$ #eep on peeling.

f there are faint or missing areas$ put it bac# down and rub some

more. f that does not wor#$ you need a bit more thinners in that area$

so rub again with a wetter area of the wad.

Here is the finished result. There are areas where the toner has run a

little bit$ but nothing that will stop the bits from being cut out

accurately.


12/178

(ow we need some 1315, suare balsa strips. %"&% &odels can again

help you out$ as they sell pac#s of * selected strips in 1J, lengths in

+arious si6es$ in both indoor and outdoor uality 8outdoor being more

robust9. Howe+er$ usually 2ust cut my own stripwood using 2ust a

steel rule and a sharp scalpel. 2ust gauge the width of the strips byeye$ so there is some +ariation$ but if you cut a good selection$ you can

sort them into groups of the same width. f some come out a bit

narrow$ 2ust use them for the uprights or diagonals.

There are proper balsa strippers on the mar#et which will allow you

to cut strips eactly to si6e - guess am 2ust a cheaps#ate.

The wood you use for the fuselage longerons and wing spars needs to

be uite hard and stiff$ as these are the main load bearing members on

the plane. "lso$ the grain of the wood you use to cut strips from needsto be straight along the length of the sheet. f it runs at an angle across

the cut strips$ it will seriously wea#en them. ood suitable for cutting

into strips may well be found in your local hobby shop.


13/178

Less than 1* minute's wor#$ and ha+e got more than enough 1315,

suare strips to finish this model. There are two stiffnesses of wood

here$ as stripped from two different sheets. The dar#er balsa in the

bac#gound is the harder$ stiffer wood.


14/178

7ight - let's startF taped together sheets 1 and < of the downloaded

plan and placed this on the building board. The whole thing is co+ered

with clingfilm$ raided from the #itchen drawer$ to stop the glue

stic#ing to the plan.

The pinning of the first part o+er the plan is always one of my

fa+ourite moments 8which probably eplains why ha+e so many half-

finished models in the house9.

%tart by cutting out 1 from the sheet$ and pinning it down on the

plan. ou can see ha+e pinned through this part$ which is not always

sensible$ but due to it's width there is little danger of splitting or

wea#ening the part ecessi+ely. (et add the front and rear lower

longerons$ gluing them to 1$ and pin down the upper longeron.

tend to put in the outer pins +ertical$ and the inner ones at an angle tohold the wood down onto the board. 0ins are placed either side of the

1315, suare strips$ and (OT through them.


15/178

The uprights and part < at the nose can now be glued into place. To

cut the uprights to the correct length$ butt them up to the top

longeron and mar# a notch in the wood at the bottom in line with the

inside of the lower longeron. Cut the wood fully through bac# on thecutting mat. Test for fit$ and ad2ust length as necessary using an

emery board until you get a snug fit. f you cut it too short$ do not

attempt to fill the gap with glue$ 2ust cut a replacement. f the fit is

correct$ you should not need pins to hold the uprights in place.


16/178

The tailpost is a little tric#y to get in place because there is not much

room for fingers$ so a pair of twee6ers can help.

>ust one upright to go on this photo. ou will notice my first


17/178

modification to the #it design here - the first fuselage bay$ behind


18/178

Build your first flying scale model - Chapter ) - Euselage

assembly

Ha+ing successfully completed the first fuselage half$ we now ha+e to ma#e

an identical second one if we want to ensure a suare and true

fuselage. %o$ pull out all the pins$ carefully remo+e the clingfilm

without disturbing the plan. (ow place the completed fuselage half

o+er the plan$ and co+er it with the clingfilm. ou should be able to

pic# up the original pin holes in the plan around the outside when you

pin it down$ through the clingfilm.

The 1 pieces and longerons are placed eactly o+er the those in the

first fuselage half. "gain$ angled pins on the inside of the frame can beused to hold the strips down. "dd all the spacers and diagonals$ plus

the nose sheeting. Be especially careful at the nose and tail to get the

uprights eactly matched to the other half.

hen it is dry$ you can remo+e the pins and ta#e off both hal+es.


19/178

"s an aside$ one ad+antage of stripping your own wood is that you can

be fairly certain that if the strips were cut from the same part of the

same sheet$ they will be of the same stiffness and strength$ and this

will gi+e you the best chance of getting a straight and symmetrical

fuselage.


20/178

t is worth spending a bit of time trimming and cleaning the frames

up$ remo+ing ecess glue with a sharp #nife blade$ and gi+ing them a

bit of a sand to smooth away any steps or rough areas.

One thing li#e to do 8and you may well thin# this o+er#ill9 is to

gently sand down the frames on a sheet of well used )5* grit wet and

dry paper which has been glued to a 0erspe offcut. This is what

used to use to sand my plastic +ac-form #its on$ but it wor#s 2ust as

well with balsa parts 8as long as you do not try to use it wet9. The

ad+antage o+er the emery boards is that there is no danger of digging

a corner in$ or accidentally sanding one area too much. use a gentle

circular motion$ and apply a bit more pressure to problem areas 8e.g.

hard lumps of glue9. =o #eep chec#ing to ma#e sure you ha+e not gonetoo far though. confess to being +ery$ +ery fussy about the

smoothness of my airframes$ as this gi+es you the best chance of a neat

and wrin#le-free co+ering 2ob. This sanding method is +ery helpful for

remo+ing any steps that may be present$ for instance an upright

standing slightly proud of a longeron. guess you really only need to

sand the outside faces$ but as said$ this is perhaps an area where


21/178

am a tad obsessi+eF

To begin assembly of the fuselage$ you will need to cut out parts E.M

and E.J. Test fit them to the fuselage hal+es$ and ad2ust the slots if

necessary to get the bottom of the formers flush with the bottom of the

fuselage frames.

There are a couple of ways of initially 2oining the fuselage hal+es

together. One method would be to glue E.M and E.J to one half$ set at

@* degrees$ then add the other half. &a#e sure the frames are parallel

when +iewed from abo+e$ and that the top longerons of both hal+es

are parallel when +iewed from the side.

thin# a more foolproof way is to 2oin the frames at the tailpost$ lining

up the top longerons so they eactly match$ then gluing in former E.J.

Chec# from the top that the triangle you ha+e formed loo#s

symmetrical when +iewed from abo+e.


22/178

hen dry$ put some glue on former M$ and suee6e the fuselage hal+es

together at the front until the longerons and #eels are snugly located

in the former cut-outs. Hold until dry.

confess this was the point where had my first brea#age. Because

the grain in formers M and J runs +ertically$ they are prone to splitting

if you suee6e them from the sides too much. (eedless to say$ that is

eactly what did. The lighter the wood you are using$ the more of anissue this will be.


23/178

This photo shows the fi$ which did after repairing the former. "ll

you need to do is glue a strip of 1315I suare balsa strip across the

bottom at right angles to the grain. also did this retrospecti+ely to

former E.J. 7emember the former could split after you ha+e finished

the model if you hold it a bit too tightly when launching$ for instance$

and it will be much more difficult to repair then.


24/178

The net former to be added is E.K at the nose. used balsa cement$

and held it in place until the glue set. The photo shows that ha+e cut

as large an opening as dare$ to ma#e it easier to get the rubber bac#

into the plane after stretch winding. The small thrust button holeshown on the original part would be hopeless. The slot at the top

centre has been reduced to 2ust 1315I deep$ so the corresponding #eel

.K will ha+e to be ad2usted to suit.


25/178

Completing the fuselage is now 2ust a matter of filling in the spaces

with more formers at the top and matching cross pieces below. "fter

cutting out the remaining formers from the sheet$ reinforced them

with 1315I strips as shown to stop me accidentally splitting them

during assembly. f you cut the matching 1315I cross pieces to eactly

match the formers$ you will ensure your fuselage sides remain suare

8you can see these laid out under their corresponding formers9.

Here we see the fuselage with all the formers and cross pieces in place.

The front upper #eel E.K has been also added$ plus the centre top


26/178

1315I suare stringer behind the coc#pit. These stabilise the structure

nicely$ before the rest of the stringers are added. To get the rear upper

stringer dead straight$ found needed to cut the slot in formers E.1*

and E.11 a bit deeper.

The #it plan seems to show the rear stringers 2ust sort of +aguely

ending in free air somewhere in front of the tailplane$ so to tidy upthis area$ added a piece of 1315, )315, soft balsa 2ust in front of the

1315, suare cross piece$ as shown here. t was notched to fit between

the longerons$ and stic#s up 13J, abo+e them. " 1315, deep notch was

cut at the centre to recei+e the top stringer.


27/178

"s mentioned before$ the front of E.K needs to be cut away inside to

clear the enlarged nose opening.

The upper 1315, suare stringers can now be added. f you add them

in pairs$ alternating between the left and right sides$ this will gi+e the

least ris# of introducing distortion in the fuselage. The wood used for

the stringers can be lighter stoc# than you used for the longerons$ as


28/178

they do not ha+e such a structural role.

The stringers underneath the nose were left off at this stage$ until the

undercarriage had been attached.

" dry run trying out the stringers in the former slots will show if you

get a nice smooth run front to rear. f the wood seems to be being

forced out of line anywhere$ open up the slot at that former in the

appropriate direction until e+erything lines up nicely. =onNt worry

about lea+ing a gap at one side of the slot$ as we will be sanding many

of the formers away between stringers later anyway. (ote that ha+enot worried at all at this stage about trimming the stringers to an

eact length - the ecess can be trimmed and sanded flush later.


29/178

This photo shows how ended the stringers in front of the tailplane

location. The outermost ones ha+e been chamfered and glued to the

top longron$ and the ones inboard of these ha+e been let into the balsa

strip added earlier. t will all be sanded smooth later.


30/178

This photo shows the most etreme eample of slot enlargement hadto do 8on former E.9. "lthough not absolutely necessary$ filled the

gaps in this case with scrap strip. The small pieces were trimmed

behind the former later 8longer lengths are easier to handle9.

ou might also spot that 8deliberately9 bro#e the top two stringers at

the position of the wing leading edge$ so would get a completely flat

run under where the wing sits. f you 2ust let the stringer run

smoothly o+er this former$ it would bulge up and interfere with the

bottom of the wing 8or am being 2ust too darned fussy againD9

n case you were wondering about the bac#wards lettering on the

formers$ this is due to the method of transfering the patterns to the

wood. "s the paper is placed face down on the wood$ you get a mirror

image produced of any lettering.

n the net chapter we will tac#le the undercarriage.


31/178

Build your first flying scale model - Chapter K - The

undercarriage

The wire used on models for undercarriages and the li#e is generally #nown

as piano wire$ which is hard and springy. t should be stoc#ed by most

good model and hobby shops.

The most common si6es used for models up to about )* inch span are


32/178

The front leg is the easier to ma#e - here are the first bends.


33/178

"nd here it is finished. There was uite a bit of twea#ing mecessary to

get the angles loo#ing eual$ and some twisting to get the wheel ales

in line and pointing in the same direction. ou can probably see from

this photo that was not 1**A accurate in my leg length - my

undercarriage came out a fraction long.

The rear legs are much harder to get right$ because they ha+e tric#y

little loops on the end and some nasty double angles that are difficult

to wor# out in )= spaceF ou can see in this photo that found the

best way to do the loops was to lea+e ecess wire as you bend them

round the tips of the pliers. ou can tighten the loops by suee6ing

them with the pliers.

&y first attempt ended up in the bin$ because got the angles

completely wrong$ and second time round disco+ered that it was

much easier to 2ust bend it to the plan +iew shape first$ as shown

abo+e.


34/178

n this photo ha+e snipped off the ecess wire from the loops$ and

put a length of spare wire through the loops to help stabilise it while

put in the final bends.


35/178

The first wire part is tac#-glued to the #eels 1 with balsa cement.

/iew the fuselage carefully from the side$ and compare the angle of

the wire legs to the plan. ou may need to twea# the wire slightly until

the legs hang +ertically. ou might as well also chec# it from the front

for symmetry while you are at it.

Eind some cotton from your wife's sewing bo$ or where+er$ cut a

length$ and glue one end inside 1 as shown with balsa cement.


36/178

(et smear some balsa cement on 1 in the area you will be binding$

and wrap the thread around the wire as shown. hen finished$ cut off

any ecess and smear some more balsa cement o+er the thread on

both sides of 1 to strengthen it.


37/178

ell$ did promise to show you e+erything$ warts and all$ and this

+iew clearly shows that got the rear legs a bit wrong. ith the loops

sprung o+er the front legs$ the rear legs 2oin the fuselage at different

points$ so the cross piece is definitely not at right angles to the

direction of flight. 4+en with my perfectionist tendencies$ decided

could li+e with this$ as did not want to ha+e to bend a replacementpart. n fact$ if you +iew the finished undercarriage from the side$

there is a slight difference in the angles of the rear struts$ but it is not

+ery noticable.

ou may notice also that cut small recesses in the #eels 1 to sit the

wire in. This was to ma#e the wire cross piece sit under the tissue on

the fuselage underside$ and hence ma#e it in+isible after co+ering.

Here is the final undercarriage all securely bound into place. (ote the

etra gussets added abo+e the front undercarriage wire - as much tohelp with the co+ering as to reinforce the 2oin. confess did use a

spot of cyano adhesi+e to tac# the rear legs onto the #eels before

bound them with balsa cement. t does ha+e its usesF


38/178

The tails#id is also made from wire and bound in place using balsa

cement and cotton - compared to the main undercarriage$ this was a

piece of ca#e.


39/178

Build your first flying scale model - Chapter - Einal

fuselage wor#

O$ let's get bac# to wor#ing with balsa again$ which is much more fun that

wire 8at least in my opinionF9

Here you can see the last stringers$ which are added under the nose.

found needed to ad2ust two of the slots in E.1< to get them

symmetrical.

hen the cement was dry$ the stringers were sanded flush at the nose$

and formers E.< and E.) added. below you can hopefully see that also

decided to cut out the inta#e opening in E.< rather than 2ust paint it

on.

Ha+ing already added some sheet inlay in the fuselage sides at the

nose$ decided to now carry this on and sheet between the stringers

abo+e and below the nose. Besides adding some useful strength where

it is needed$ this is also +ery satisfying wor# to do$ and a useful

techniue to learn for future models. ou could probably get away

with using soft 1315I sheet for this$ but prefer )3)


40/178

are in+ol+ed$ to ma#e sure you can lea+e enough wood stic#ing up to

sand down later to the correct contours.

Ta#e a piece of soft balsa sheet$ and cut a strip across the grain$ so the

width of the strip is 2ust a touch greater than the gap between formers

E.K and E.. ou can get the final fit using an emery board. Offer up

the wood to the longeron$ and mar# roughly where the net stringerup meets the sheet of wood 8front and bac#9. Cut the sheet between

the mar#s. (ow offer it up to the space you are trying to fill$ and see

how the fit loo#s.


41/178

Gsing an emery board$ sand the four edges until a snug fit is obtained$

with the sheet sitting proud of the stringers and formers. ou will

probably ha+e to sand chamfered angles on all four sides. There will

be a lot of trying for fit$ ta#ing a bit more off$ trying again$ trimming a

bit more$ and so on. Try to lea+e no gaps at all around the edge. f it

ta#es a couple of attempts to get the piece to fit$ then so be it Q you willget faster the more you do$ and because the wood is soft$ shaping the

parts is relati+ely fast. hen happy with the fit Q glue in place with

the aliphatic wood glue.


42/178

"s you wor# up the fuselage$ the angles get more interesting$ and you

ha+e to shape the bottom edge of the sheet before you can mar# the

top.

Here is the completed filled upper fuselage (et was the section at the

bottom between E.K and E.1


43/178

The outermost pieces here were done a slightly different way$ in that

they were simply slid in from the side$ and sit on the lower longerons

The centre two pieces are done li#e the upper cowling$ and are let in

as normal.


44/178

Once the glue is hard$ the upstanding bloc#s of sheet can be car+ed

roughly to shape with a sharp blade. The stringers act as your guide

as to how much wood to remo+e. Here is the nose prior to sanding.


45/178

(et$ final shaping is carried out using emery boards$ followed by a

final polishI with 5** grit wet and dry paper 8used dry$ of course9.


46/178

n this +iew you can see that ha+e also started to shape the nose

laminations$ and ha+e rounded off the bottom corners.

"s mentioned$ find this wor# +ery satisfying to do$ but as we are all

different$ it is uite possible you will not. n which case$ this step can

be easily omitted Q at least you ha+e the side sheeting to get a firm gripon while winding the model.

tac#led the coc#pit sides net. The #it design features a notepaper

pattern which is glued o+er the balsa structure. This is simple to do$but as usual decided to change things$ on the grounds that paper is

easily damaged and creased by careless handling of the model. much

prefer to use balsa for coc#pit openings - in this case soft 1315, sheet.


47/178

ou can see in this photo how used the paper pattern as a guide forcutting out my four pieces of balsa.

Here is the first piece glued in place. ha+e deliberately left it slightly

proud. Einal shaping of the opening and blending bac# to the rest of

the structure is done after the glue is dry$


48/178

"ll four coc#pit pieces ha+e been fitted and shaped in this +iew. ou

can also see the two small filler pieces added behind the headrest to

gi+e me someting to stic# the tissue to later. "lso the sheet pieces forthe rubber retaining dowel$ and the scalloping out of the formers$

both detailed below.

The #it shows a relati+ely large hole for the rubber dowel$ but if you


49/178

use a length of aluminium tube 8fairly standard amongst flyers

nowadays9 the hole does not need to be this large. usually ma#e the

holes with a round needle file li#e this. Best to lea+e it a bit undersi6ed

at this stage.

7eturning to those former scallops - this is the sanding bloc# usually

use to help with this. &ade by R-"cto$ ha+e had it for years. li#e

the different shapes of the two ends ends - the small radius is +ery

useful when sanding between stringers that are +ery close together.The larger one for when they are further apart. et and dry

sandpaper is wrapped round it - possibly )5* grit - can't remember.


50/178

Here it is in action. The reason for remo+ing the wood between the

formers is simply to stop it showing through the tissue after co+ering.

f only the stringers show$ it loo#s much neater.


51/178

(othing to stop you ma#ing a set of home made bloc#s yourself$ of

course$ or 2ust rolling the wet and dry paper round a section of dowel

of suitable diameter. ou could e+en 2ust hac# out the wood between

the stringers with your modelling #nife - it would not loo# +ery neat$

but nobody is going to see after you ha+e co+ered the model.


52/178

Einal 2ob was to open up the hole in the nose formers ready to accept a

nose plug. The shape is not too critical$ but it needs to be as large as

you thin# you can get away with$ so the rubber will fit through it

comfortably while stretch-winding. ou will see how modified an

emery board by cutting it much thinner to use as a sanding aid.


53/178

Here is the final nose shape after a bit more sanding - at one point at

the lower corner you can see daylight is beginning to show as ha+e

rounded it off so much. e will worry about the nose button in a later

chapter.

To gi+e you an idea of a target weight$ my completed fuselage came

out at 5 grams 8using a postal scale accurate to *. gram9.


54/178

Build your first flying scale model - Chapter 5 - Elying

surfaces

n this chapter we will construct the wings$ tailplane and fin. The wings are

built directly o+er the plan$ which should be co+ered with cling film or

something similar$ as we did with the fuselage sides.

ou will need to cut some strip from a light3medium sheet of 1315,

balsa - enough )315, wide for the leading edge$ and tailplane cross

pieces$ and 13K, wide for the trailing edge. e can get away with

using light wood because the sections are generous for an 1J, span

model.

Begin by pinning the leading and trailing edges to the board. ou can

see ha+e dared to pin some of the bits through the balsa strip - with

wood of this si6e and lightness splitting is ne+er a problem. The wing

tip pieces are net$ and the edges of these need to be carefully trimmed

and ad2usted so they fit snugly. &a#e sure the outer edges at least

cross the oulines drawn on the plan - we will sand bac# to the final


55/178

shape after remo+al from the board.

found it easier to fit the centre tip piece 8.


56/178

The wing ribs can now be added$ gluing them to the leading and

trailing edges. "fter you ha+e cut the wing ribs out it is a good idea to

smooth their upper surfaces with an emery board. n fact$ if you want

to be really fussy$ you can pin the ribs together in a bloc#$ lining up

the spar slots with a scrap bit of 131J, 1315, strip$ then sand the

whole bloc# together so all the ribs are eactly the same shape. confess on this model did not bother.

The photo abo+e illustrates something strange about the ribs 7.) on

the printed sheet. "fter cutting them out$ you will notice that one of

them is smaller than all the rest. cannot belie+e it is a coincidence

that the short rib loo#s 2ust the right si6e for the outermost rib$ where

the trailing edge has started to cur+e. %trange that there is only one

though. &aybe the original intent was to ha+e two ribs called 7.K to

use at this position. "nyway$ cut down one of the larger 7.) ribs to

match the smaller one$ and used them in the outermost positions.

f you are luc#y$ the ribs will be a nice snug fit between the leading

and trailing edges$ and they will stay in place without outside

interference while the glue dries. %et them at roughly @* degrees to the

building board using .1 eyeball. n this picture you can see the

highly sophisticated ,bottle of glue and scalpel, method of holding a


57/178

loose rib in place.

The root rib is one where you do need to be accurate about setting the

angle correctly. The guide from the plan was stuc# to a scrap piece of

balsa and cut out to use as shown here.


58/178

(et stage is to add the 1315, 13J, spars. These were cut from

medium hard 1315, sheet$ as they ha+e to ta#e the main bending loads

on the wings. ou can lea+e ecess at the root ribs$ but stop them half

way into the outermost rib as shown here. " separate section is added

between here and the tip pieces.


59/178

Einal stages are the addition of the two tip pieces and the gussets at

the wing roots on the leading end trailing edges. left the gussets

where the spar meets the root rib until later in case needed to ma#e

any surgical ad2ustments when setting the correct dihedral.

%pea#ing of gussets$ ma#e sure you get the grain in the correct

direction - if you cut them from a strip li#e this you can't go wrong.


60/178

"fter remo+al from the board$ the net step is to sand the wing tips

until the outline matches the plan. hile you are at it$ ma#e sure both

wings match each other. t is not unusual to find some discrepanciesbetween left and right wings on a plan.

Here is a potential wea# spot that needed filling with a scrap of 1315,

sheet. f you read this before cutting the ribs out$ you would be best

lea+ing ecess wood here on the outermost ribs to sa+e a filling 2ob

later on.


61/178

(ow it is time to shape the wing to a nice smooth aerofoil section. This

+iew of the root rib shows the sort of thing you are aiming for.

"t the trailing edge you are only remo+ing wood from the top$ and

this photo gi+es you an idea of how far to #eep sanding. " sharp

trailing edge will loo# better$ and of course the more wood you sand

off$ the lighter the wing will be.


62/178

There is less wood to remo+e on the leading edge$ and unli#e the

trailing edge$ this is rounded top and bottom. &a#e sure the profile of

the ribs is smooth and blends bac# without any steps to the leading

and trailing edges. "lso try to get the upper spar flush with the tops of

the ribs.

Before gluing the wing hal+es together$ chec# that the two root ribs

match as closely as possible in shape - it will loo# better afterwards.

could not see a recommended tip dihedral on the plan$ and test

fitting indicated a total of about


63/178

with 2ust 13


64/178

Einal gussets are now added to the centre section. ou can see ha+e

added four at the spar 2oin instead of two. Two would ha+e been

enough to reinforce the dihedral 2oin$ but four gi+es a better chance of

not getting wrin#les here after co+ering. The etra two gussets at the

front are purely added as an anti-wrin#le aid - these corners areprime wrin#le territory.


65/178

Here is e+erything sanded smooth.

e can turn our attention to the tailplane now$ which is almost

entirely constructed using parts cut from the printed sheets. Hopefully

you used nice light sheet to copy the parts onto$ so we can ha+e a nice

light tailplane. " bit of weight sa+ed at the rear will sa+e a lot more at

the front in terms of noseweight no longer needed.


66/178

ou should be used to the drill now - co+er the plan with clingfilm and

pin the parts down o+er the plan. "s with the wings$ "liphatic wood

glue was used throughout.

ou will find a bit of ad2ustment necessary to ma#e the parts fit

snugly$ but found generally the bits went together fine.

%omething always do with flat plate tailplanes now is rub them

gently on a sheet of wet and dry emery paper glued to a flat board

until there are no steps to be felt when you rub your fingertips o+er

them. This needs to be done both sides. find this method much less


67/178

fraught than trying to do it one 2oin at a time using an emery board.

Here is the finished item after sanding the outline to match the plan$

and rounding off all the edges.

The final piece is the fin$ which simply needs cutting out and its edges

rounding off as shown here.


68/178

Time for another weight chec#. "ll the bits made so far placed on the

postal scale come to a total of 2ust @ grams$ which is most satisfactory.

n the net chapter we will be loo#ing at the stage you ha+e all been

loo#ing forwards to 8or secretly dreading9 - co+eringF


69/178

Build your first flying scale model - Chapter M - Co+ering

the fuselage

4+en after a lifetime of building models$ somehow ne+er really loo#

forwards to the co+ering process. t still goes wrong for me sometimes$

and end up stripping a piece off to redo it. ou can gi+e yourself the

best chance of a successful co+ering 2ob by ha+ing as smooth an

airframe as possible$ with gussets strategically positioned in high ris#

wrin#le 6ones.

The type of tissue you use will also be important. Here is a selection

from my stash:

The best you can get in my opinion is 4sa#i tissue 8on the right of the

picture9$ often called >apanese tissue. This is +ery light and has a

smooth finish which seals well with 2ust a thin coat of dope or rylon.

t is a+ailable in se+eral colours and if you use the chal#ing techniue

8about which more later9 this can be epanded to a much larger range

of possible colours. store my tissue rolled up in a cardboard tube. "


70/178

good source for this tissue is &i#e oodhouse - his web site is

www.freeflightsupplies.co.u#. ood +alue$ high uality and post free

if you buy a reasonable stoc#.

n the middle is a selection of %"&% %uper LiteI tissue$ which comes

in a huge range of colours. This would come under the rather broaddescription of domestic tissueI. t is hea+ier than 4sa#i$ but uite

adeuate for most models$ where weight sa+ing is not of ultimate

importance. Clic# herefor the rele+ant page on the %"&% &odels

web site. 4asy Built &odels sell something similar in the G% - ha+e a

loo# here. ou can also get luc#y in card and gift wrap shops

sometimes$ pic#ing up coloured tissue that can be used for models.

Beware though that some may not be colour fast$ and also may possess

no wet strength 8an important factor when you come to water-

shrin#ingF9 Hallmar# produce some metallic tissue sheets that

apparently wor# well for models.

On the left are some old sheets of a tissue which used eclusi+ely

when first started out Q this was called &odelspan$ and could be

bought in both lightweight and hea+yweight forms. t is a soft tissue$

which is uite forgi+ing of double cur+es. Only drawbac# was that it

has uite an open wea+e$ so soa#s up a fair amount of dope before you

got a smooth non-porous surface.

Before commencing co+ering$ we need to wor# out how we wish tofinish the model. n this case will be doing the all-blue scheme with

sil+er trim and lettering. see the following possibilities:

? Co+er the model with blue tissue$ cut out lettering and trim from sil+er

tissue and attach. f you cannot find sil+er tissue$ spray some white

tissue with sil+er paint 8e.g. =esign &aster floral spray9. Gse glue stic#

to attach mar#ings.

? "s abo+e$ but chal# the blue tissue with blue pastel chal# before you

apply it to ma#e it more opaue. Clic# herefor an ecellent tutorialon how to do this.

? 0aint the model o+erall blue after co+ering$ then mas# and spray all the

sil+er mar#ings.

? 0aint the model o+erall blue after co+ering and apply mar#ings from cut-

out pieces of sil+er decal sheet.
http://www.freeflightsupplies.co.uk/http://www.samsmodels.demon.co.uk/Catsectionb.htmlhttp://www.easybuiltmodels.com/ebl.htmhttp://www.easybuiltmodels.com/chalk.htmhttp://www.easybuiltmodels.com/chalk.htmhttp://www.freeflightsupplies.co.uk/http://www.samsmodels.demon.co.uk/Catsectionb.htmlhttp://www.easybuiltmodels.com/ebl.htmhttp://www.easybuiltmodels.com/chalk.htm


71/178

am going for the last mentioned method$ as the mar#ings are

relati+ely large$ and so fairly simple to cut out. ou also a+oid the ris#

of the mas#ing tape pulling off the blue paint. (ote that to get the

decals to adhere properly$ you will need a gloss finish on the model.

The model will be co+ered with blue 4sa#i tissue to minimise the

amount of paint needed later to pro+ide a good co+erage Q it also

shows up better on photographs$ ma#ing it easier to see what is going

on.

One common uestion is which side of the tissue to put outwards - the

rough or the shiny sideD do not thin# it really matters +ery much to

be honest. tend to co+er rough side out 8remember rough is only a

relati+e term - perhaps matt would be a better description9 because

thin# the paint #eys slightly better than to the shiny side. Eor a doped

coloured tissue finish$ you may prefer to co+er shiny side out.

am going to use the dope and thinners method to attach my tissue.

0lease do not thin# this is the only way to do it$ it is 2ust the method

am most comfortable with. " lot of people use glue stic#s now$ or

thinned down 0/" wood glue. hope to add an appendi later

detailing these alternati+e methods$ but in the meantime$ here is how

do it.


72/178

The first step is to apply a generous coat of sanding sealer where+er

you want the tissue to stic#. %o$ the edges of the wings and tailplane$

the fuselage longerons$ all the sheeted areas$ stringers and tailpost.=onN forget the outermost wing ribs on the top$ as we will be using two

pieces of tissue on each wing uppersurfaces.

&a#e sure you do this in a well +entilated area$ as this stuff is really

smelly. ou may need to send the rest of the family out for the day......


73/178

hen it is dry$ gently sand off any fu66 with a bit of wet and dry

paper$ or fine sandpaper.


74/178

(ow add a bead of full strength nitrate dope o+er the sanding sealer.

%ome people recommend two coats of sanding sealer plus dope$ but it

seems to stic# fine for me with 2ust the one.


75/178

LetNs start with a fuselage side. f you place the tissue o+er the plan 8or

a copy of the plan if you do not want to damage itF9 you can cut out a

piece of tissue to fill the area between the two longerons. (o need to

get it eact Q safer to lea+e ecess all round. ou should really use a

brand new blade for cutting tissue$ to a+oid tears and rough edges.

need to bring up the sub2ect of tissue grain at this point. &ost tissue

types 8including 4sa#i9 ha+e a pronounced grain 8similar to balsa9$dictated by the distribution of fibres. enerally the tissue should be

cut so that the grain runs along the longest dimension of the part you

are going to co+er. To determine the grain direction in a sheet$ simply

start a tear near a corner. The tear will run straight and true in the

grain direction$ but if you try to tear across the grain$ you will get a

ragged shape$ and the tear will try to turn the corner to follow the

grain direction. ou will usually find the grain runs parallel to the

longest side of the sheet of tissue.


76/178

0osition the tissue on the fuselage and using an old brush$ apply a dab

of dope thinners to the nose sheeting. ou will ha+e a few seconds

before it stic#s fast$ so ma#e sure the tissue lines up with the balsa

frame.


77/178

This close-up shows how ha+e cut a slit in the tissue to clear the wire

undercarriage.

(ow wor# your way bac#wards down the fuselage$ applying thinners

as you go$ smoothing the tissue outwards o+er the longerons.


78/178

The slightly dar#er patches you can see on the tissue show where the

thinners has been applied.

f you get a crease$ or it starts to go wrong$ 2ust lift it up and try again.

f it has already grabbed and you want to reposition$ apply more

thinners which will soften the dope$ and you can lift and reposition. t

is normal for the tissue to loo# a bit loose at this stage Q 2ust ma#e sure

there are no ma2or folds or creases.


79/178

"fter the thinners ha+e dried thoroughly 8 minutes at the most9 you

need to trim off the ecess tissue. ou can use a brand new scalpel

blade as shown here$ or sand off the edges with a small piece of wet

and dry emery paper as shown below.


80/178

The finer grit$ the less ris# of a ragged edge - 5** grit wor#s fine.

usually use a combination of both techniues.


81/178

"fter co+ering the other fuselage side$ it is time to tac#le the bottom.

ou can see that did not try to match the shape at all at the bac#$ but

did cut the piece of tissue so it was a reasonable fit at the front. This

was achie+ed by simple trial and error - cut$ test fit$ cut a bit more etc.

ou will also need to cut slits to clear the rear undercarriage wires.

Once happy with the shape$ start to apply this piece to the airframe

from the rear$ and attach it with thinners until you get to the cross

piece where the nose stringers start.


82/178

thought there was a good chance that the lower stringer area could

be co+ered with the same piece of tissue$ without slitting it$ if it was

wetted first$ so had a go. f wrin#les did appear$ then those sections

could always be cut out later and replaced.

ater was applied with a brush$ then the tissue eased o+er thestringers and lower nose sheeting. t was smoothed out until it loo#ed

li#e this.


83/178

(et$ dope thinners were applied to the edges and all of the lower nose

sheeting$ through the damp tissue.


84/178

Here is the same area after the tissue had dried out. Happily tight as a

drum$ and not a wrin#le in sight. The ecess at the front was trimmed$

then dampened again$ smoothed around the front$ and stuc# to the

nose former with more thinners.


85/178

Here is the fuselage bottom after the edges behind the undercarriage

had been trimmed 8in this case using emery paper9.

The net stage is to wor# our way up the fuselage$ adding strips of


86/178

tissue between the stringers. or#ing up rather than down has the

ad+antage of gi+ing o+erlaps that face down$ ma#ing the steps in the

tissue less +isible in normal +iewing of the model.

e are relying on the dope applied to the airframe to act as adhesi+e

for the tissue$ so we ob+iously ha+e a bit of a problem on the toplongeron$ because this is now co+ered with tissue. Thus$ before we add

the net strip of tissue$ we ha+e to brush a bead of full strength nitrate

dope along the longeron$ on top of the tissue. f you get some dope on

the tissue below the longeron$ wipe it off uic#ly$ as it can cause a

wrin#le in the tissue as it dries and shrin#s.

" piece of tissue must now be cut which fits neatly on the bottom edge

along the upper longeron. (o need to worry too much about the top$

as this will be trimmed afterwards. This photo shows my piece of

tissue being test fitted. etting the shape right is again 2ust a case of

trial and error. find a steel rule helpful in trimming the tissue edges

on a the cutting board with a scalpel blade.

The tissue is attached with dope thinners$ li#e the fuselage sides were$

wor#ing from front to bac#.


87/178

Behind the coc#pit$ found was able to use one piece of tissue to

co+er two bays - the triangular section$ and the one abo+e it$ as shown

here. Before adding this piece$ it is of course necessary to apply the

bead of dope o+er the tissue on the first stringer abo+e the upperlongeron.


88/178

n front of the coc#pit$ you will need to add two separate strips of

tissue to get up to the same height. This photo highlights the fact that

when you o+erlap pieces of dar# coloured tissue$ you get an unsightly

dar#er stripe. Gsing chal#ed tissue will reduce this effect

considerably. f it bothers you$ 2ust try to #eep the o+erlaps as small as

possible 8which means you ha+e to be +ery eact in how you cut your

tissue pieces9. Because will be painting the model$ can safely say it

does not worry me at all.


89/178

" small piece of tissue fills the gap to the centreline$ lea+ing 2ust one

piece to go. The last piece is the only one that has to be trimmed

accurately both sides. 7emember to apply beads of dope either side

before attaching using dope thinners.


90/178

Behind the headrest$ found you could get away with one piece of

tissue to fill the gap$ spanning two bays.

Here you see the final co+ered fuselage$ awaiting water-shrin#ing

using the high-tech apparatus illustrated. ou can use any old

household spray bottle$ emptied of course and filled with water.


91/178

i+e it a good spray$ and you will find the beads of water tend to sit

on the surface without wetting it. Li#e this in fact.

ipe o+er the tissue with your finger to spread the water out and it

will wet the surface properly$ as shown here. (ow 2ust lea+e it to dry

in its own time.

t is uite possible to ta#e a more sophisticated approach to water-

shrin#ing than demonstrated here. Eor instance$ if you get hold of an

old perfume atomiser and fill it with water$ this will allow you to coat

your model with a fine layer of 8delicately scented9 water droplets. Eor

a gentler shrin#$ you can spray the droplets into the air$ then waft themodel parts through the mist. This could be a good techniue if you

are building a more delicate model than this one.


92/178

Here is the finished result$ which than#fully shows no wrin#les.

was a bit worried about this area$ with the undercarriage binding$

but seem to ha+e got away with it.


93/178

/iew of the rear dec#ing$ again showing e+erthing nice and smooth.

The net step will be to co+er the flying surfaces.


94/178

Build your first flying scale model - Chapter J - Co+ering

the flying surfaces

(ot sure why$ but the tops of the wings seem to be the most difficult parts of

a model aircraft to co+er neatly - especially if as in this case the

leading edge is right at the bottom of the section. Eor this reason

tend to co+er the top first$ to get it o+er with.

%o$ we need to cut a piece of tissue to co+er between the centre and

outermost ribs. To minimise the sag between ribs$ ma#e sure the

tissue grain runs spanwise.


95/178

Line the tissue up wih the frame and apply a spot of dope thinners to

the gusset where the top spar 2oins the centre rib.


96/178

(ow slosh some thinners through the tissue on the leading and

training edges$ and easing the tissue outwards with your thumbs$

wor# your way down the wing$ pushing the tissue onto the wood.

"s you mo+e towards the tips$ apply more thinners as you go.

7emember we are only stic#ing the tissue to the centre rib$ tip rib and

leading and trailing edges - (OT any of the other ribs.


97/178

hen you get to the last rib$ chec# that the tissue is sitting nicely on

the outermost rib. ou sometimes find you ha+e ecess loose tissue$ so

to a+oid a wrin#le$ ease the tissue out more towards the trailing edge$

and try to chase the ecess out along the trailing edge - wor#ing bac#

towards the centre of the wing again. ou may need to apply morethinners through the tissue so it will still slide o+er the doped balsa.


98/178

hen dry$ the ecess tissue at the leading edge can be trimmed with a

scalpel$ then any o+erlap at the end rib$ as shown here. The tissue at

the trailing edge can be trimmed using emery paper or a scalpel.


99/178

" bead of full strength dope is applied carefully along the top of the

outmost rib and allowed to dry.


100/178

The separate tissue tip piece is added in the usual way by flooding

dope thinners through the tissue.


101/178

"nd here it is trimmed.

The underside is much simpler as it is flat and can be co+ered in 2ust

one piece of tissue. Trim the ecess tissue using your fa+oured method$

then repeat the whole process for the other wing.

put this photo in to show the less than drum tight finish you would

epect to ha+e at this stage$ %o if your tissue loo#s a bit li#e this$ don't

panicF


102/178

e are going to ha+e to hold the wing flat while the tissue is water

shrun#$ and use a pair of balsa offcuts$ 13J, thic# to hold the wing

off the wor# surface. This allows air to get under the wing$ and helps

the underside to dry out.

%hrin# one wing at a time - here the panel has been sprayed with


103/178

water on both sides.

ou may ha+e noticed a small piece of wood in the photo before last -

this is what it is used for. t is inserted at the trailing edge of the wing

tip prior to adding the weights. The purpose is to loc# in a small

amount of washout at the wing tip 8less incidence$ or angle of attac#$

at the wing tip than at the wing root9. On some models the addition of

this washout can ma#e the difference between a ha+ing a laterally

stable or unstable model. t is +ery probable that a naturally stabledesign li#e the %wift with ample dihedral would wor# perfectly well

without any washout at all$ but do tend to build it in as standard on

all my models ,2ust in case,. On the %wift am adding 1315, washout

to each wingtip.

e could get into a more complicated discussion here about using

differential washout on both tips to help control the flight pattern$ but

thin# that will ha+e to wait for another article.


104/178

/ery useful things$ spice 2ars.

Here is the result after both wings ha+e been shrun#. ou may be

surprised 2ust how strong and rigid the wing has now become.


105/178

This photo ma#es an interesting comparison to the pre-shrin#ing shot.

"lthough not completely perfect$ at least the ma2or leading edge

wrin#le has been a+oided and am sure the etra gussets helped.

Turning our attention to the tailplane - this is +ery simple to co+er

with one piece of tissue each side.


106/178

The edges being trimmed with emery paper

"nd the finished article co+ered on both sides.

The bare balsa edges do stand out a bit when using dar# coloured

tissue$ which is not an issue if you are going to paint the model$ but


107/178

will be if you are relying on a coloured tissue finish. n this case$ trim

the upper piece with a sharp #nife lea+ing a bit of an o+erlap. 7un a

wet finger round the edge$ and stic# down by flooding dope thinners

through the tissue. f you want to go a less smelly route$ stic# the edge

down with a glue stic#.

The abo+e applies eually to the wings$ of course.

"t this point$ to a+oid being sued by people who auire bad scalds$

ought to say ,=O('T T7 TH% "T HO&4,

nstead will 2ust say$ ,be careful,. t might be sensible to wear

glo+es while you do this 8 didn't$ which suppose ma#es me wildlyirresponsible9

hy am doing such a thingD ell$ a full water soa# on this part$

which is considerably more fragile than the wing 8especially with the

light wood used9 is going to ma#e it end up loo#ing li#e a potato

crisp 8or chip to our "merican friends9. t will 2ust not cope well with


108/178

the shrin#age. (ow you could use alcohol to shrin# the tissue$ which is

gentler than water$ or you could waft it o+er a boiling #ettle li#e did.

The tissue can be seen starting to go limp - when this happens$ place

on a flat surface and weight it down while the tissue dries.

said spice 2ars were useful. f there are still areas that loo# a bit

wa+y after it dries$ you can steam again$ or if the problem is +ery

localised$ 2ust lic# your finger and apply to the problem area.

"ctually$ this tric# can be used on any part if you ha+e a wrin#le after

the first water shrin#. There seems to be something in sali+a which

helps to gi+e that little etra shrin# you sometimes need to get rid of

an obstinate wrin#le. Eaintly disgusting$ but there you are.


109/178

0roof of flatness photoF This is what your tailplane should loo# li#e

after the tissue has been shrun#. f it comes out warped$ bite the

bullet$ strip the tissue off$ and try again. ou are bound to ha+e

problems later on flying a model with a warped tailplane.

Time for a uestion - should the fin be co+ered or notD f you are


110/178

going for a coloured tissue finish$ the answer is ob+iously yes. f a

painted finish$ you don't ha+e to$ but it will gi+e a more e+en surface

appearance to the model$ and hide the wood grain of the part. ou

will also need less paint to gi+e the reuired match to the rest of the

airframe. would thin# it adds a bit of strength too.

/ery easy to do - 2ust attach an o+ersi6ed piece of tissue to both sides.

The fin has pre+iously had a coat of sanding sealer all o+er$ followed

by a coat of full strength dope. The tissue is 2ust cut from the sheet

and applied dry$ by flooding dope thinners through it. f you co+er

both sides at the same time there is less chance of the part warping.

There is no need to water-shrin# the tissue.

Here is the trimmed item - used emery paper to remo+e the ecess

tissue. f you find you ha+e some loose tissue edges$ run a damp finger

around the perimeter$ and then brush dope thinners around the edge.

The damp tissue will be more happy to sit down neatly at the edges

than dry tissue.


111/178

"ll that remains is to dope all the parts we ha+e co+ered and shrun#

in the last two chapters. am a belie+er in the principle that all the

necessary shrin#ing should ha+e already been done by the time we

come to dope the model. f you ha+e wrin#les at this point$ you are not

going to get rid of them using shrin#ing dope.

use non-shrin# dope eclusi+ely - the stuff in the old preser+e 2ar

here is thinned *3* with dope thinners$ and the whole model will

recei+e 2ust one coat.

use an old flat brush to apply the dope and try to get a nice e+en

coat. t is easy to see where you ha+e applied the dope while it is wet$

because the tissue goes almost transparent. Thus you should not miss

a bit. This process is etremely smelly$ so ta#e it outside if you can$ or

at least to a well +entilated spot.


112/178

4+en though the dope is sold as non-shrin#ing dope$ see no point in

ta#ing chances. Thus$ the wings and tailplane get weighted down for a

second time for a couple of hours while the dope dries completely. Let

it flash off before doing this$ otherwise they could stic# rather messily

to the wor# surface. (o need to do this with the fuselage or fin though.

Loo#ing at this photo$ am sure there are times when my long

suffering wife wishes had a different$ less smelly hobby$ which too#

place rather further from the #itchen.


113/178

Time for another weight chec#. Here are all the parts made to date$

co+ered and doped and ready for assembly. am +ery happy with 1)

grams so far - it will be interesting to see how much the paint and

details will add.


114/178

Build your first flying scale model - Chapter @ - 0rop$

wheels and final details

>ust one or too final 2obs to do before assembling the model. Eirstly ma#ing

the headrest from paper. This can be simply cut out from the plan$

and the folds of the two tabs scored with the bac# of a modelling #nife.

The paper can be formed by rubbing it o+er the edge of a table as

shown here. t will cur+e li#e this$ which helps when fitting o+er the

headrest former.


115/178

found needed to alter the shape a little as shown to stop it

o+erlapping the balsa former at the top.

GHG all purpose glue was used to attach the headrest$ applying

adhesi+e to both tabs and under the front face. f you get glue


116/178

anywhere you don't want it$ dope thinners wor#s well at remo+ing it.

The headrest was gi+en a coat of sanding sealer$ plus about 13J inch

onto the fuselage both sides. " specially cut piece of dry tissue was

then applied o+er the white part and attached by flooding dope

thinners through the tissue. The sanding sealer o+erlap onto fuselage

ensures that the edges stay stuc# down as well.

(otepaper was also used to create the main undercarriage struts. "


117/178

strip was cut$ scored and folded as shown.

" length was cut to match the length of the wire leg. found it

necessary to cut away the inside face as shown to get a neat fit.

To gi+e the paper fairing a nice streamlined shape$ it was rubbed o+erthe edge of a ruler to curl the paper. The inside faces were gi+en a

layer of GHG glue$ and the fairing folded o+er the wire leg 8fold at the

front9. "ny ecess glue that emerges from the 2oin at the rear can be

remo+ed with dope thinners.


118/178

Here are the finished legs - thin# they loo# so much better than 2ust

a s#inny piece of wire.

Time to thin# about the propeller and remo+able nose bloc# now. This

might be a good time to decide what we are going to stic# on the front

of our Comper %wift.


119/178

Here are a selection of possible propellers we could use.

On the left$ 2ust for a laugh$ is an original /eron plastic prop from a

1@*'s Tru-Elite #it. t is inch diameter$ has tiny blades$ and they do

not ha+e any twist in them at all. This is one of the reasons we tended

to only get powered glides out of these models when we bought and

built the #its as youngsters.

(et 8mo+ing left to right9 we ha+e a M inch 0ec# 0olymers prop. This

is the one Chris %trachan uses on his %wift$ and also had success with

one of these on my second Tru-Elite >odel Bebe.

To the right of this are a Tern 5 incher$ and a modern 7" copy ofthe same prop. The Tern is +ery popular with scale model flyers$

including myself$ because it has generous blade area for its diameter

and a decent amount of pitch. The freewheel clutch is a wea# point$

howe+er$ and can strip at inappropriate moments - the 7" +ersion

is beefed up in this area. The genuine Terns can be spotted by the

letter T engra+ed on the prop blades.


120/178

Einally$ in red$ we ha+e a newcomer to the scene$ a 5 inch prop by

"7" designed by the famous C6ech modeller Loubomir outny.

am loo#ing forwards to trying this one out on my =iels (a#a2ima

iK)$ as it has more pitch than a standard 0ec# prop$ and could be a

+iable alternati+e to the Tern. t also has the ad+antage of being

perfectly balanced when you buy it.

Elitehoo# in the G can supply all the illustrated props 8apart from

the old /eron oneF9 and %"&% &odels can supply all but the "7"

one. Both offer an efficient mail order ser+ice.

Eor this model decided to stic# to the tried and tested Tern 5, prop.

e need a nose bushing as well as a prop$ and find the 0ec#

0olymers nylon ones as good as any. f you want a cle+er ad2ustable

one$ then 0 "ero &odels ma#e a nice one 8see Gseful "dressespage9.

=ue to the lac# of room in the nose of the %wift 2ust went for the

smallest 0ec# item.

(ote these can be bought with different internal diameters either

13)


121/178

hat you COGL= do is drill out the prop and re-bush it with some

aluminium or brass tube of a slightly smaller internal diameter. hat

actually did was smear cyano glue on a spare piece of wire$ and push

it through the prop a few times. The glue collects on the inside of the

prop hole and when it sets$ the hole is a bit smaller. did the same

with the nose bush. %hoc#ing really. %till$ it is uic#$ and seems towor#$ and the cyano glue is probably harder than the plastic used for

the prop and bush$ so wear should not be an issue.

e need to ma#e a remo+able nose plug$ and thin# it would also be a

good idea to face the seating for this plug with some thin ply. This will

resist wear$ and should mean that if during the trimming you add a

sli+er of downthrust$ it will not dig into the balsa nose when the motor

is fuly wound$ and thus change the thrust angle.

auired a large sheet of 135K, ply a few years ago from a trader at a

model show$ and thin# it will turn out to be a lifetime's supply. t is

etremely useful as a thin facing material. Here you can see a disc

being cut out of the plywood using an Olfa Compass Cutter. This is a+ery useful tool for cutting out perfect circles in wood or paper. t is

also relati+ely inepensi+e and should be a+ailable in most good art

and craft shops.


122/178

" hole was cut in the front of the disc to roughly mimic the hole we

ha+e in the nose$ The disc was then attached to the fuselage nose with

Cyano.


123/178

hen the glue was set$ the aperture was trimmed with a sharp #nife

to eactly match the hole in the balsa nose. could also not resist

sanding the top and sides of the nose to ma#e sure the ply blended in

reasonably with the nose. The bare balsa areas show without doubtwhy it would ha+e been better to fit this disc B4EO74 co+ering

8especially if you are planning a coloured tissue finish9

The remo+able nose plug is made from two components plus the nylon

nose bush. On the left is the part that fits inside the nose$ laminated

from three sheets of 1315, hard balsa. " hole was cut in the middle of


124/178

each lamination to roughly clear the nylon bush.

in the centre is the front of the plug$ which is laminated from a second

135K, ply disc plus < laminations of hard 1315, sheet. "ll of these were

cut out using the Compass Cutter. " hole was opened up in the centre

with a round needle file to gi+e a tight fit to the bac# of the nylonbush.

hat may not be too clear from this picture is that the front of the

this part had an angle sanded into it. To gi+e you an idea how much$

at one side the front 1315, lamination was ta#en down to less than

13)


125/178

(ow glue on the front of the plug$ ma#ing sure you only put glue on

the plug rear$ not the fuselage nose. "d2ust the position of the plug so

that the angled front points down and slightly to the right.

hen the glue is completely set$ pull out the plug. Hopefully it will not

lea+e the rear part in the fuselageF The (ylon bush can now be glued

in position 8using cyano9. ou will probably ha+e to open out the hole

in the rear plug portion a bit more with a round needle file$ to ta#e

account of the angle.


126/178

(ow the plug can be firmly pushed into the nose$ and shaped to match

the nose contours as well as possible. This plug came out rather small$

and thin# if was doing it again$ would follow Chris %trachan's

eample and use his ,half a nose bloc#, method. That would certainly

gi+e you a bigger opening to get the rubber through.


127/178

By putting a length of wire into the bush$ you can see the downthrust

angle. ha+e ta#en a guess at this$ as most high wing models reuire

at least some downthrust. ha+e not measured the angle$ but as usual

used the TL"7 principle 8That Loo#s "bout 7ight9. Time will tell if

got it right....

The wheels shown on the plan are a bit undersi6e$ and the plastic

wheels supplied with the #it would ha+e also been rather too thin forrealism. %eems a good opportunity to show you how ma#e laminated

balsa wheels though$ so let's ma#e a new pair.

The real Comper swift had uite fat little tyres on it so decided to

laminate each wheel from K discs of )3)< sheet. The centre two solid$

and the outer ones with a hole in the middle to represent the tyres.

4ight balsa disca were cut out of light )3)


128/178

Eour of these had the centres cut out$ again using the compass cutter$

but this time set to its smallest radius. This is much harder to do than

the outer cut$ and seems to wor# best if you use a chopping action

with the blade as you wor# your way round. ou will most li#ely ha+e

to finish off with a sharp #nife.

Here are all the bits for two wheels


129/178

Before laminating$ find it much easier to shape the inner contours of

the tyre now rather than later. ou can start things off using the more

pointy end of a sanding bloc# as shown here.


130/178

"nother useful tool is a roll of wet and dry sandpaper. ou can wrap

this round a dowel$ or 2ust use freehand as shown here. The inner hole

is unli#ely to be perfectly round$ so 2ust play around until it loo#s

reasonable. Gse the two neatest ones for the ouside of the wheels.

(ow we can laminate all four bits together. use "liphatic wood glue

for this$ and place a weight on top to hold the laminations together

while it dries. f your centre holes are not perfectly concentric$ ignore

the outside$ and centre the tyre on the compass hole in the middle of

the centre laminate.


131/178

hen e+erything is set$ a piece of tube needs to be inserted through

the centre of the wheel to act as a bearing. ou can use aluminium$

brass or plastic 8which is what used9. ha+e what is probably a

lifetime stoc# of assorted etruded plastic rod$ strut and tube

produced by Contrail for the plastic model mar#et.

The hole made by the Compass Cutter needs to be enlarged first. ou

could do this with a small drill$ but li#e to use a round needle file to

gradually open up the hole$ wor#ing from both sides$ until the tube is

a comfortable push fit.

nsert one end of the tube into the wheel$ and rotate the tube between

your fingers to see if the wheel runs true. f not$ ad2ust accordingly

and try again. hen satisfied that the wheel is running more or less

wobble-free$ apply some cyano where the tube 2oins the wheel on both

sides.

Two options now. ou can lea+e one end of the tube etra long$ thenuse this to mount the wheel in a hobby drill$ so you can use it li#e a

lathe while you shape the tyre with sandpaper. "luminium tube would

wor# better for this than plastic as it is much stronger and stiffer.


132/178

"lternati+ely$ stic#ing to the minimal tools approach$ 2ust cut off the

tube close to the hub$ and car+e and sand the outer profile of the tyre

by hand. f you #eep loo#ing at it end on$ you can ma#e sure that thesection through the wheel is constant on both sides$ and consistent

round the wheel. ithout turning the wheel in a drill$ you are ne+er

going to get it perfect$ but once on the model$ any iregularities will be

hardly noticable. Here are before and after photos. hen finished$

gi+e each wheel ) coats of sanding sealer$ gently sanding between

coats.

The final parts that need ma#ing before painting are the wing struts$


133/178

which are simply cut from 1315, sheet$ and all the edges rounded off

to gi+e a +aguely streamlined section. 4ach of these pieces will

produce two struts$ but they do not need to be cut to length until after

painting. f you are going for a coloured tissue finish$ they need to be

co+ered with tissue. Otherwise 2ust gi+e them a couple of coats of

sanding sealer.


134/178

Build your first flying scale model - Chapter 1* -

"ssembly and painting

usually li#e to assemble my models before painting$ unless this would ma#e

the mas#ing difficult. ith this colour scheme there is no mas#ing$ so

assembling first was the ob+ious route$ a+oiding the possibility of

getting glue on the paint later on.

The ing was first glued to the fuselage$ chec#ing that the leading

edge is positioned as shown on the side +iew on the plan. used balsa

cement to attach the centre wing ribs to the upper #eel. %ome time

should be spent ma#ing sure it is suare to the fuselage when +iewed

from abo+e. found that the result was not particulary stiff$ and you

could still roc# the wing slightly when +iewed from the front$ e+en

after the glue was dry. The wing struts will stabilise things$ but

found also needed to insert a small balsa pac#ing piece as shown

here to get the wing dihedral loo#ing symmetrical when +iewed fromthe front.


135/178

(et$ the tailplane was glued into position$ ma#ing sure it was suare

to the fuselage$ and that it loo#ed correct relati+e to the wing when

+iewed from the front and rear. Before attaching the fin$ pric#ed a

series of holes along the centreline of the tailplane with a pin. do this

to try and encourage some wood to wood contact when the glue is

applied 8balsa cement again9. The glue should hopefully tra+el at leasta little down the holes$ and pro+ide a #ey. Otherwise$ all you ha+e

attached the fin to is the tissue. f using balsa cement$ the base of the

fin 8which is end grain9 needs to be pre-sealed with a thin coat of

cement b

build your first flying scale model

Documents