Sopwith Pup (Build Instructions)

Specifications Wingspan: 38cm Length: 29cm Flying Weight: 46grams Channels: 3 (Rudder Elevator Throttle) Suggested Receiver: 4Ch Micro Motor: 7mm Geared Motor

Airframe Kit (Included Contents) * Airframe Covering Parts (balsa) * Airframe Skeleton (hardwood) * Carbon pushrods * Wheels and rubber tyre rings * Fine sand paper * Control linkages * Decals

Needed to Complete

* Thick CA Glue * Micro Phillips Head Screwdriver * Long nose fine pliers * Hobby Knife * Ruler * Household Pins * Hobby Masking or Other Tape * Tweezers * Small Screwdriver * Felt pen

* Patience * Keen Eyesight * Steady Hands * Receiver Transmitter Charger Battery * Motor and Propeller (see instructions for suggested RC gear setup)

Battery Options

The Nanotech 300mah 1S battery is recommended for best balance.

If using the Nanotech 160mah or similar battery, you will also need to add some

ballast to the nose.

Before You Start

This airframe has been designed to fit together easily with all components precision drilled and

CNC cut from high quality balsa and paulownia wood. However, you will be working with very

small components, so you will need patience and keen eyesight. We recommend working in a very

well lit area and taking a break between stages to rest the eyes and hands. Most of all, take your

time, enjoy the building experience and you will be proud of what you have produced in the end.

First, refer to this and the following pages to ensure that you have all the required airframe

components in your kit.

Decal Stickers

Airframe Wooden Parts

Additional Parts

Before starting you may wish to lightly sand

down all the flat surfaces of the parts if you

want to have a smooth finish. It’s easier to

do this initially, especially in areas such as

the wings where ribs will get in the way of

sanding when complete.

When removing parts from the sheets, identify where the cut line is sectioned and cut that part

with a sharp pointed hobby knife. The parts should be able to be removed easily. Never twist or

bend the parts back and forth to remove them as this will damage the parts. Instead cut around

the parts as necessary to easily remove them.

Glue together the control system mount as shown below. Allow this part of the frame to dry

before gluing in place the X shape piece on the front.

Construct the circular mounting frame and screw in the control system mount. This is temporary

and just holds everything in place while the rest of the frame is being constructed and is drying.

Your frame will look like the image on the left. Now it’s time to glue in place the C shaped part

and make the frame look like the image on the right. Once again note the orientation of the

control system mount when gluing in the C shaped piece.

Slot in without gluing, one of the 4 parts you set aside earlier to hold this C shaped part square

while drying.

Set these 4 parts aside for the next step

Note Orientation – The two cut out for lugs are at the bottom.

Screw in screws temporarily

Screw in from this side

Then glue in place the rear most part with the two protrusions each side. Once again use the 4

braces put aside earlier to hold this square while drying. Then go ahead and glue those 4 parts in

place.

We are now ready to start work on the fuselage. Identify and cut out the parts shown. Then glue

them in place as shown in the image. Allow time for each part to dry before gluing the next.

Longer one to top

Keep the middle hole underneath clear of glue when

gluing on the top supports. The bottom hardwood

formers slot into there.

Ensure that the second hole in from either side is clear of glue as another

part needs to slot in there in the next step.

These lugs are closer to the top at the end

which glues too the balsa.

Attach the part you have just made to the hardwood frame. Ensure all parts are glued at 90

degrees angles. Set aside to dry.

Score or crease the side panels as shown here (do not cut). Then gently bend them to about 10

degrees. You can also cut out the elongated pushrod slots at this point.

Do not glue the sides together at

the back. The tail skid will be

inserted in here later.

Glue the sides of the fuselage on

but be sure to leave these parts

open to be glued onto the frame

later when attaching the top and

bottom plates.

Score and bend

Note the orientation of this part when gluing on the rear

fuselage frame to make sure you glue these two pieces

together the correct way.

Use a sharp hobby knife to cut out these panels. Then bend the bottom plate where shown.

Glue on the bottom plate. Glue down the sides to meet flush and tape with modelling tape if

needed. The perforated section of this plate will later be cut out to form the hatch cover.

Note that the plate should NOT be glued at the front or back here.

Before gluing in place the top plate, wet it with some water and slightly bend it as shown. Allow to

dry before gluing in place.

Cut panels out

Score and bend

Score and bend the tail piece up to match the body line.

Attach the tail skid. Look from the back and make any adjustments to the body alignment while

gluing.

Also cut out the bottom hatch plate. Some scrap wood can be used to glue across the hatch on

the inside surface to strengthen it.

Glue in two magnets into the holes as shown here. Ensure that you test the magnets to make

sure they will attract correctly to close the hatch. Also glue on the front hatch lugs. These may

need to be sanded or the holes in the hardwood frame cleaned out and scraped to allow the lugs

to insert easily. Also sand the edges a little.

Next remove the parts below to make the cowl. Be careful to remove the parts with the stepped

edges in one piece as shown here. These pieces are used as a template to position the other cowl

pieces before being cut away later. Start by gluing in the magnets as shown.

Glue the parts in place as shown below. Note that the first ring you put on will be lower than the

second one. This is to allow for the balsa sheet to wrap around and sit flush.

When gluing on the balsa sheets look for the positioning lugs on the hardwood frame which are

used as a starting and finishing point to wrap the balsa from.

Finally, cut away the positioning pieces and sand the cowl to smooth the edges.

Magnets

The other three magnets need to be inserted in the holes in the fuselage. However you must take

care to align them the right way. First attach the magnets to the ones in the cowl and with a black

felt pen mark the side facing you and ensure that side of the magnet is orientated the same when

it is glued into the fuselage hardwood frame. Lay the cowl down in front of the fuselage and

transfer one magnet at a time to the fuselage frame and glue it in so the black dot is facing the

rear of the fuselage.

Finally, take this opportunity to give the whole fuselage a light sand down. It’s easier to sand it

down now than with wings and tail-plane attached.

Before sanding After sanding

Take the wheel pieces and glue in the plastic hub pieces as shown in the image on the right below.

Then glue on the center piece with the holes in it. Be sure to glue the center piece with the grain

at 90 degrees to the two outer pieces to give additional strength.

Important: The o-rings need to be stretched a slight bit to

fit them on. Allow the wheel hubs to fully dry before

attaching the o-rings, otherwise the o-rings will separate the

discs of the wheel hubs.

Carefully put the o-rings on and glue them in place.

Next we will attach the ribs to the upper wings.

The upper wings are the ones which do not have the

long cut out pieces near the wing root.

Note that as in the image to the left, we only need 3

ribs per wing. The second set of slots in from the wing

tips are used for the wing braces which attach to the

upper and lower wigs.

Also ensure that you do not use these ribs with the cut-outs on top. These two ribs are for the

wing root of the lower wings.

Glue in place the wing ribs as shown here. However, do not glue the wings together. There is

another section which needs to be glued in between the two wing pieces.

Now prepare the lower wings.

Note that if you intend to attach the decals to the wings, it

is common to have the decals on the bottom surface of the

lower wings. You may wish to attach your decals before you

glue the last rib on. If so, then glue in the ribs either side of

where the decal goes to curve the wing surface. Then attach

the decal. Cut out slots for the rib with a hobby knife if

needed and then glue the last rib over the decal.

Leading Edge

Glue in the ribs taking note that the two ribs with the cut outs go closest to the wing root.

Also, note that the holes used to glue on the wing braces are directly in line with a rib. After

gluing in that rib, turn the wing over and clear out any glue from the wing brace slots.

The wings will look like this when completed. Don’t glue them together!

Screw on the top wing supports. The support goes on the outer side of the lug which is attached

to the fuselage.

Keep these holes clear of glue

Leading Edge

Screw in here

Now glue on the central wing section and the wings. Ensure that the wings match smoothly with

the top surface of the inner wing section. You can use some thin model masking tape to tape the

two surfaces together to keep them level with each other. Also smear some glue on the joint line

under the wing where the two wing parts join.

Glue in place the lower wings. Then glue in the wing struts between the upper and lower wings.

At his stage you may also want to check your

wings are level and don’t have any slight twists.

Look from the front and identify any twists in

the wings. These can be corrected by rubbing a

“very small amount” of water on the wing

surface and twisting it gently till it dries.

Screw the wheel struts together as shown here.

Then screw the wheel struts in place to the airframe. The bent section is toward the front of the

airframe and the screw head near the wheel is on the inner side, while the screw heads near the

fuselage are on the outer side.

Feed through the axel and put the wheel on. It is a good idea to cut two additional pieces of heat

shrink to go on the inside between the wheel struts. Heat and fix them in place to stop the wheel

struts from moving.

Cut some pieces from the larger heat shrink tube. Apply some heat (such as from a soldering iron)

to shrink them to the carbon.

Attach two small pieces

of heat shrink here to

stop the wheel struts

from moving in.

Attach here to keep the

wheels on

You may wish to add a piece between the wheel and the

undercarriage frame as well (which is not shrunk) to act as

a spacer. Cut the carbon axel to size with a hobby knife. A

small amount of glue on the end only will also help hold it in

place.

Use the hinge strips provided and glue them in place as shown. The balsa attaching the control

surfaces will be cut away later. It is there to hold the surfaces straight. Also glue in the piece

which joins the tail surfaces. At this point you also need to check if the control horns need to go

on the left or right. Set out your control system and check this. If you have a programmable

transmitter then servo channels can easily be swapped in the case that you are using a brick style

receiver with onboard servos.

IMPORTANT NOTE:

We recommend that you use crossed pushrods in this setup. This means for example that the

servo on the right side of the fuselage connects to the control surface horn on the left of the

fuselage. This allows for a clear line of travel from the servo to the control horn.

Do the same with the vertical stabilizer

Hinge strips

Longer support leg

Hinge strips

Glue the tail-plane horizontal stabilizer in place and then glue the vertical stabilizer in place on top.

Check to make sure they are level and square.

The bottom hinge also needs to be glued in place.

Next build the motor mount. There are two options for powering this model – a brushed motor

or a brushless motor. See below for how to build the motor mount for each option.

MicronWings suggests using a brushed motor setup, and in this manual we will detail the

suggested setup for a brushed motor.

Brushed Motor Mount

Hinge

Congratulations.

Your airframe should now look like this.

If using a brushed motor, MicronWings suggests using a Gearbox 7mm Twin Drive Horizontally

Opposed Base Mount. This motor’s mounting holes align with the mounting holes in the motor

mount supplied with the kit.

Gearbox 7mm Twin Drive Horizontally Opposed Base Mount

Website Product Link

Website Product Link

Brushless Motor Mount

A brushless motor mount is also supplied for builders who wish to mount a brushless motor

instead. MicronWing doesn’t supply motor / ESC and receiver setups for brushless options. We

reccomned using a brushed motor setup on this model.

Radio Gear

It’s now time to install your radio gear and servos. Note that this kit does not include receiver,

servos, battery, motor, propeller, charger or connectors. The information below is simply a

guideline for setting up the system.

The airframe is designed to accomoadate 1.7 gram 5320 SH servos. These servos will screw in

neatly to the frame. The receiver board being used in this example is a 4Ch DSM2 / DSMX

receiver with an onboard 2A brushed ESC. Note that for this receiver you need to use the 5320 SH

servos which have 1mm pitch connetors, not the standard 5320 servos which have Molex

connectors.

The receiver can be attached using hook and loop tape or by using a micro tie-clip. Here, other

tie-clips have been used to bundle the servo and motor wires underneath the radio gear mounting

board.

Bundle and tie wires here Leave this area free for mounting the battery.

The list of products below is suggested to complete the setup shown here.

4Ch DSM2 / DSMX Receiver with 2A ESC (The recommended receiver option for this model)

Receiver 24R6CLV11 DSM2 (A good option if you prefer a brick type Rx instead)

Servo 5320 Black SH (Most 5320 servos come with Molex 1.27mm connectors.

For the receiver above you need the 5320 SH version)

Micro Connectors 2mm Round 2 Pin (for connecting motor wires to receiver board)

28 AWG Silicone Coated Wire (Used for connecting the motor connectors to the Rx)

Heat Shrink

Gearbox 7mm Twin Drive Horizontally Opposed

140mm Prop

Nano-Tech 300Mah Battery (This size battery will also assist in balancing the plane)

Mole Battery Connectors (Used to make an adapter lead for the 300mah battery)

JST mCP-X Connectors DIY Connectors (Used to make an adapter lead for the 300mah battery)

Feed the control rods through the fuselage and connect them to the servos. Remember the

control horn on the right should be controlled by the servo on the left and so on. Be sure to turn

on your transmitter and receiver and center the servo arms and trims on the transmitter before

you do this. Use the provided clips and attach them with heat shrink to the pushrods and clip

them onto the servos.

You will need to shorten the servo arms so they clear the airframe

inside. Cut off the end hole to leave just two holes and attach the

pushrod to the second hole from the centre.

Attach only this control linkage to the ends of the two control rods.

Use a dab of glue to tack them in place and cut a short length of

heat shrink from the tube to cover them with. The glue is important

because when the heat shrink is heated the glue heats up and binds

the pushrod and heat shrink together. Heat the heat shrink with a

soldering iron or something else hot. Then insert these and connect

them to the servo arms.

Then insert the gear mount into the fusealge and secure it by

screwing it in place with the 4 screws at the front and two at the

rear.

Leave the control surface parts as they are for now. The next thing

you need to do is set up your transmitter. Turn it on and connect

the battery to the receiver and check it is all working correctly. Look

at which way the pushrods are moving and reverse the servo

direction on the transmitter settings if needed. Make sure all the

trims are centred.

Tack glue the linkages with the hoop in them to the pushrods at the

correct position and apply heat shrink. The hoop can be contracted or exapnded to make manual

adjustments to the control surface. Further adjustment can be made using the trims on the

transmitter.

Note that once this part is done you will no longer be able to remove the bracket which holds the

RC gear and servos without first undoing the control

linkages near the control surfaces.

You can now cut away the balsa parts which are

holding the control surfaces in place.

Then test your system to make sure it is all

functioning correctly.

Next we need to set the correct balance point for the plane. Use the positioning of the battery to

adjust the balance point.

Recommended balance point: 10mm back from the leading edge of the lower wings.

The cowl also needs to be attached before the propeller is

pressed onto the shaft. To do this you will need a pair of long

nose pliers as there is limited gap to access the shaft. Follow

the procedure shown in the video below.

Balance Point: XXmm

This video explains the best

method to press the propeller

onto the shaft of the geardrive

without bending the geardrive

shaft.

Balance Point: 10mm from leading edge of the bottom wing

The longer screw is attached as shown in the image below and the supplied lead weight wrapped

around it to add more weight to the nose. Note that even with the suggested 300mah battery you

will still need this additional ballast weight. This is because this is a true scale model and the nose

is relatively short.

Control Surface Deflection

The images below, although not of this particular model, show the correct amount of control

surface deflection needed. Use these images as a guide to how much maximum deflection you will

need on the control surfaces. Do not exceed this amount of throw on the rudder as it will cause

plane to roll to an excessive amount. You will most likely need to dial down your throws on your

transmitter to around 50 to 60 percent. We also suggest that you set the differential to about

35% if your transmitter supports this function.

You’re now ready for test flying.

Perform a test glide a few times in an area

with soft long grass. On the first flight start

off with low power and do a short straight

flight to land straight ahead. From there, try

more power and gentle turns till you learn

how much rudder deflection is required for

a gentle turn.

A sample flight video.

Take-off and Landing Video 01

Take-off and Landing Video 02

Copyright © MicronWings 2017: All rights reserved.

This manual is for personal use only. No unauthorized copying or digital distributing permitted

without permission from MicronWings.