(Build Instructions) Specifications * Wingspan: 58cm * Length: 50cm * Flying Weight: 59 grams * Channels: 3 (Rudder Elevator Throttle) * Suggested Receiver: 4Ch Micro * Motor: 8mm GearDrive * Prop: GWS 4025 (Supplied) * Alternate Props Up to GWS 5030 Included in Airframe Kit * Airframe Parts * Geardrive, motor and prop * Wooden Wing Braces * Wooden Servo Mounts * Carbon Struts * Control Horns and Linkages / Pushrods * Sandpaper * Double Sided Mounting Tape * Rubber Bands * VELCRO Brand Super Fine Dots Needed to Complete * Hot Glue Gun * UHU Expanded Polystyrene Glue (link) * Hobby Knife * Pliers to cut carbon rod * Ruler (preferably steel) * Blenderm Hinge Tape (link) * Masking Tape or Household Pins * Soldering Iron to heat the heat shrink * Sanding Block * Small Screwdriver * Battery Charger and Batteries * Transmitter, Receiver and Servos (see instructions for suggested RC setup)
Before You Start This airframe has been designed with school students and first time indoor flyers in mind. The build process is simple, but some careful sanding of the parts is necessary. Follow the instructions below for a trouble-free build process. Two types of glue are required for this build and each type of glue has its specific purpose. Use UHU Expanded Polystyrene glue on all joints except where Glue Gun Hot Glue is specified. Glue Gun hot glue is used when we need to fill a void or gap around the part we are gluing. UHU Expanded Polystyrene Glue is used for bonding foam and wooden parts together. UHU is usually applied to both surfaces and allowed to dry before bringing the surfaces together for an instant bond. However, in some cases where we need to parts to move against each other as we bring them into position, for this we don t allow the glue to dry before bringing the parts together or we may just add a thicker layer of glue to one surface. A note on using UHU Expanded Polystyrene Glue When applying this glue, most people use too much glue. You should apply the glue straight from the tube and then spread or thin it out with a piece of scrap foam to leave just a thin film of glue on the surface. If you put too much glue on, scrape some off before gluing the parts together. This is too much glue. It won t dry properly and the joint will be weak. The correct amount of glue. A thin film of glue on the surface. Use a sharp hobby knife to cut the parts from the sheets.
The tail surfaces and matching control surfaces where they meet need to be cut at an angle on one side to allow them to pivot. To do this, place a metal ruler on top of the surface flush with the edge and press down as you cut at a 45 degree angle back underneath the ruler. The control surfaces will look like this from the edge. These are the surfaces which need to be cut at 45 degrees. Lay the rudder control surface and tail section out like this to ensure you cut the correct side of each surface. Sand the tail plane and rudder control surfaces on all edges on both sides. (except the edges you just cut the 45 degree bevel into) Laying the longer edges flush with a table edge will support the surface while you are sanding. You may choose to simply bevel both sides or you may wish to make them more rounded. These are the surfaces you need to bevel on both sides. The wings have a top and a bottom. The top of the wing has these half cut lines. Sand a bevel into the wings on three sides except this edge where the wings will join together. Once again, put the wing on the edge of a flat surface to support it as you sand. Sand a bevel on the top surface which goes down at least half way at this angle. Then sand a smaller bevel on the lower surface. You may wish to further sand the edge to round the bevel off (this is optional) An example of the completed surface
The wings will form a V shape when glued together as indicated by the plywood wing struts. So we need to sand the ends of the wings to have a VERY SLIGHT angle. This angle only needs to be about 2 degrees as shown below so just a few rubs of the sandpaper is adequate. About 2 degrees Note: if you hold the wings together at this stage there will be a large gap in the middle, but this gap will disappear when the leading and trailing edges are bent. To give the wings an airfoil shape we need to bend them along the half cut lines. Support the wing on the edge of a table and use a ruler to evenly bend the wing at both of the half cut lines. Bend it down about 30 degrees till you hear the foam crack. Glue 3 ribs in place under each wing. These notches indicate the position of each rib. Make sure the ribs run at 90 degrees to the leading edge of the wing. The side of the rib with the three straight edges is glued to the wing. Glue only this side of the wooden spar to the foam Glue the wooden wing spars to one wing. Only apply glue to the wooden wing spar for this joint. Make sure the wing spar is flush with the top and bottom surfaces of the wing. Apply glue to both surfaces where the foam wings join as well as to one side of the plywood wing spars and glue the wings together as shown.
Sand the three foam sections under the wing where the wings join to take the ridge off and flatten the surface there a little. Glue these two sets of pieces together as shown in the photo. Glue these pieces under the wings as shown. Note the correct orientation of the front piece as shown here. Use UHU Expanded Polystyrene glue to glue in place the four carbon wing rods. These are glued into the grooves where the foam bends and also to the wooden wing spars. You can either apply the glue to the carbon rod or apply the glue to the groove. Press the carbon rod down into the groove so it is below the surface. Sand the grooves on the top of the wing to make the surface smooth. The gaps between the foam and wooden wing spars on the under side of the wings can then be filled in with glue gun hot glue. Apply it in sections and scrape off any excess before it dries. Note: We do not recommend using hot glue to fill the grooves on the top of the wing as the hot glue will leave a rough residue on the wing surface even if scraped off and this could affect airflow over the wings. Sand the plywood locating former to bevel it on both sides. This will allow it to slot into the groove on the fuselage easily without damaging the foam.
---------------------------------------------------------------------------------------------------------------------- Glue the fuselage pieces together and lay it on a flat surface to keep it straight as it dries. Glue the 2mm square x 13cm long carbon rod into the middle of the slot in the fuselage. Use a small amount of glue on the upper and lower surfaces of the carbon rod where it touches the foam. Start here and work around to the front Must be flush with top Glue in place the two side pieces. For these, just apply the glue to the side piece and spread it out thin. To allow the side piece to be moved and positioned, don t apply glue to the main fuselage piece. Take your time with this stage. The gaps must match exactly and the top of the side piece must be perfectly flush with the top of the fuselage. 90 degrees Ensure that this slot is aligned on all pieces and forms a 90 degree angle with the fuselage. Glue in the motor mount as shown here. Note the orientation of the slot which slopes toward the right hand side of the airframe to give right thrust to the motor. For this part, apply more glue than usual to both surfaces and the back edge and insert it straight away before the glue has a chance to dry. This will allow the piece to be moved and positioned. Right Thrust Front of airplane Insert the 2mm square x 4.5cm carbon rod into the motor housing as shown. Don t glue this part in. The motor will be secured to the airframe later by a spot of hot glue.sand both ends of the carbon rod to remove any burrs and allow it to fit in easier.
These two surfaces must be flush with the foam side part below Glue these wing supports to both sides of the fuselage. Use the rectangular cutout as a guide to placement. Mark out the area to apply glue to with a pen and just apply the glue to the fuselage to allow the part you are attaching to be moved a little to get it in the correct position. Slot the wings into the fuselage by aligning the wing spar tab with the slot in the top of the fuselage. Note: you may need to trim the fuselage wall at the front here to allow the wings to slide in firmly. Glue the servo mounts in place as shown here. Glue on both ends as well as the side where it sits against the main fuselage part. Use Glue Gun hot glue to glue the motor shaft in. Inject some glue into the mounting hole and apply some to the carbon rod. Also apply some glue to the back of the motor and where the fuselage touches the motor at the bottom. The motor will have about 3 degrees of right thrust and the prop hub will be aligned to be directly over the centre-line of the airframe. Attach the control surfaces to the horizontal stabilizer and vertical stabilizer with Blenderm hinge tape. You may wish to pin the pieces to a mat to keep them in place while applying the tape. Ensure there is a 1mm gap between them. Do the same with the vertical stabilizer.
Attach the control horns. The vertical stabilizer control horn must go on the opposite side to the side with the bevel cut into it as shown here. The horizontal stabilizer horn goes on the opposite side to the vertical stabilizer horn. Glue the horizontal stabilizer in place. As the two surfaces need to slide on each other to insert the stabilizer, use more glue than usual and only apply the glue to the horizontal stabilizer. There is a notch on the back of the stabilizer to help align it. Glue the H shaped joiners in place as shown here to the horizontal stabilizer. Then glue the horizontal fuselage parts to the airframe and also glue them into the gaps at each end. Glue into the gaps in the H shaped joiner and fuselage side. Sand the ends of the 3cm round poles to round the ends off. Then insert them into the airframe in front and behind the wings. Fill these two holes up with Hot Glue to secure the poles in place. 40mm Use UHU Expanded Polystyrene glue to glue the flat carbon rod under the fuselage. Measure back 40mm from the front of the fuselage. For this joint apply a thin film of glue to the foam and the carbon rod and allow to fully dry before bringing the surfaces together.
---------------------------------------------------------------------------------------------------------------------- Attach the wings with rubber bands and check that they are at 90 degrees to the fuselage and level with the tail plane. If the wings are not level, lightly sand down the foam wing support on the high side till the wings sit level. Next you may wish to sand down the fuselage. If you intend mounting an FPV camera on the front, keep this part flat. The fuselage after having the corners sanded down. Radio Gear Fit-out The kit includes all control linkages and pushrods needed. However, you need to supply your own radio gear. Here, we give an example of the suggested radio gear setup. Because of the size of this model, we recommend a receiver and servo setup over a brick style receiver with linear servos. The servo mounts included and servo cutouts in the airframe are designed for 1.7 gram 5320 servos. A receiver with an onboard 2 amp ESC is needed to power the included 8mm geardrive motor. Suggested Receivers Receiver 4Ch FrSky With 2A ESC Receiver 4Ch DSMX With 2A ESC DT Rx33 Receiver
Servo Compatible with above receivers Servo 5320 Black Battery We recommend a 240 to 380 Mah 1S battery 240mah 300mah 380mah Mount the servos and screw them onto the mounting plates. Depending on the screws you are using you may need to drill out the holes in the servo mount a little. Here we have cut a gap in the foam to keep the servo lead tidy. The receiver can be mounted anywhere on the airframe. We ve chosen to mount it on top so it is accessible for the servo leads on each side of the airframe. If mounting the receiver on one side of the airframe, cut a small hole through the airframe for one of the servo leads to pass through. Attach the Z links to one end of the carbon pushrods. You may wish to use a small amount of UHU Expanded Polystyrene glue under the heat shrink to form a strong bond when the heat shrink is heated up and shrunk. Attach these rods to the servos and lay them along the fuselage on top of the elevator. Use a ruler to make sure the control surfaces are level with the horizontal and vertical stabilizers. Use some pins or wrap some masking tape around the ends of the pivot joint to hold the control surface level. This will keep it in the correct position while we attach the pushrods.
IMPORTANT Before going any further, set the trims on your transmitter to neutral. Also, move the servos and check that the arm is moving in the correct direction (up down left right) and reverse direction if needed. You may also wish to connect the rudder servo to the aileron port on the receiver if you feel more comfortable turning with the aileron stick instead having all control on one stick. Trim the pushrods about 5mm short of the hole in the control horn. Apply heatshrink to the connection at the control horn. IMPORTANT Remove pins and masking tape from control surfaces before testing them. Adjust the trim on the transmitter if any small adjustments are needed to ensure all control surfaces are level with their stabilizer surface. 36mm Attach the wings to the airframe. The centre of balance should be 36mm from the leading edge of the wings. Use the supplied VELCRO Brand Super Fine Dots to attach the battery to the airframe. The image below shows the approximate location of the battery to achieve the correct centre of balance.
This airframe is supplied with a GWS 4025 prop which gives good flight times above 30 minutes with a 300mah battery as well as good docile flight characteristics. However, propellers up to GWS 5030 in size can also be used. A 5030 prop will give more speed and better climb rates. You will most likely need to dial down the amount of throw on the control surfaces. Most good transmitters allow you to do this. Use the images below as a guide as to how much throw is required.
Airframe Overview Video Flight Video - Outside Flight Video - Indoors Copyright MicronWings 2018: All rights reserved. This manual is for personal use only. No unauthorized copying or digital distributing permitted without permission from MicronWings.