This is my first instructable and my first attempt of making a 3CH RC Plane and as a hobbyist I really enjoyed making, its a low wing type aerobatic flying model with ailerons and elevator (NO RUDDER), I started doing this project last year in my summer vacations, with my brother and it took us around 2 months to complete it.This aircraft is made totally using thermocol (Polystyrene) sheet and packing tapes used for reinforcement.
Using a very light material and shaping it to perfection was the most challenging part in this project, but somehow we managed to do it and fabrication was the part which took a lot of time here. The total size of the airplane is 42" x 36" and it weighs approximately 900 grams.
As this was my first try for making any RC plane, it did not turn out to be that perfect. It flies great though, had to do some adjustments on the transmitter and servos before getting it in the air. But do give it a try if you're really interested in making your own flying model like this for less money.
Your comments and suggestions would be highly appreciated and would also help me to make better instructables for all in future.
Good luck to all the RC pilots!!!
Step 1: Things You Need.
The materials required for this project are:
1. Polystyrene sheet (50" x 50") , 2 nos.
2. Masking tape, 2 rolls.
3. Hot Glue
1. Brushless motor 1100KvA, 1 nos.
2. Servo, 2 nos.
3. 4CH Transmitter and Reciever (But only 3 channels are required, as there are only ailerons and elevator).
4. Propeller 3 x 10".
5. 11.1 V 3 cell battery(I have used a 2200 mAh battery here).
Paper cutter, glue gun, hacksaw, pliers, drill machine, scissors.
Step 2: Getting Started
Download the given pdf plan, print it and paste on the thermocol sheet as shown in the above pictures.
Step 3: Cutting the Thermocol and Shaping It
After you have successfully completed the step 2, cut out the thermocol carefully using a paper cutter.
Cut out the wings, fuselage and the middle part separately, carefully and sand it to get a perfect shape.
After cutting and sanding the edges, try and arrange in such a way that it should look as shown in the last two images shown above.
- Make sure that the wings, ailerons, elevator and the fuselage are of the same length as in the printed plan
- To get a fine cut in the theromcol sheet, you can heat the cutter on a candle and then use it through the sheet to avoid tearing of the sheet and get fine edges and a perfect slice.
Step 4: Shaping the Wing
After you are done cutting the wing, cut out the aileron part separately.
Taper one side of the aileron, to give it enough room for movement as shown in the above picture.
Use masking tape to reinforce the thermocol. Apply the tape in layers, to give it a smooth finish.
Step 5: Servo Cut-outs
I have used only two servos in this plane, 1 for the ailerons and 1 for the elevator.
Make a groove of the same size as the servo through the fuselage so the servo arm can be extended and freely move on each side.
Cut out another groove for another servo for elevator movement as seen in the picture above.
Make sure that the grooves and of the same size so the servo can be fixed in it properly and should not be loose from any side otherwise it will effect the servo operation.
Apply enough hot glue so that the servo fixes and gets sticked inside the groove properly.
Step 6: Reinforcement and Installation of Motor
Cover the whole plane using masking tape, apply layer by layer to reinforce the thermocol and also to make it rigid. After that use any coloured tape to cover the whole aircraft and add some aesthetics to it. You can also use heat shrinkable sheet as well.
I have used an 1100 Kv Motor here, that comes with its own mount. Cut out a small piece of wood of size 2" x 2.5". Drill holes according to the motor mounts.
Place the wooden piece at the front of the fuselage by making a same sized groove in it, and apply hot glue to fix it properly.
Keep the motor there and screw it to the wooden piece properly, Use cable ties also if necessary, to add more support to it.
Similarly connect the ESC to the motor and extend the wire till the middle of the aircraft where you will place your receiver (RX).
Step 7: Wings Placement, Control Horns and Landing Gear
Mark the wing area on the body of the aircraft as mentioned in the plan.
Take two long BBQ sticks, use them as a supporting member for the wings, pinch the sticks through the body of the aircraft in such a way that it should be of the equal length on both the sides.
Mark two points on the wing as the same distance in the BBQ sticks.
Use a drill to make holes in the wing, and once done, slide the wing carefully on the BBQ sticks. This provides the wing firm hold with the body of the aircraft. Apply glue to fix is properly and rigidly.
Once the wings are attached, you can make the control horns, using either wooden sticks or buy them separately.
For the servo control again I have used BBQ sticks, attached with small piece of wire or paper clips, for which you can find DIY videos on youtube.
I also made a landing gear for it using a clothes hanger, which can be seen in the above pictures.
Step 8: Finding the C.G of the Aircraft and Battery Placement
To find out the CG of the aircraft you can either do it in the manual way which is that you tie a thread on the front and back end of the aircraft and try to balance it in such a way that the nose remains slightly upwards. Mark the center of the thread then and bring it straight down to the body of the aircraft, this will be your C.G.
You can also check for the point marked in the plan, and then trace it on the body of the aircraft.
This will also be the area where you will place your battery. Make a cut out of the size of the battery exactly over the area where you have marked your C.G. The battery should fit exactly into the cut-out so it doesnt fall out while flying and also to balance the weight equally in all parts of the aircraft.
Step 9: Final Touches and Adding All Components
Last is to install all the components and then again checking the weight and C.G of the aircraft (preferably by the manual method). Try and keep all components in such a way that the whole weight of the plane balances equally on each side. Make sure to keep the nose slightly high as this will give you a better flight.
Once you're done with this, just program your transmitter and you are good to go with flying your scratch built RC plane.