Introduction: Fokker E.III 1:8 for Aircombat
This is a presentation of how to build a WWI scaled airplane model from scratch.
It is in scale 1:8 under rules which we use for air combat competitions with such models.
This exact model flew in more than 30 competitions and won many cups. As many times we crash in the air with opponents, after about 60 rounds for 7 minutes in the air it came to its final crash, so it is gone now, but as for a memory of it being a perfect fighter in the air I decided to present it here, so you can build it too.
Step 1: Let's Start
First find a decent building plane, there are many available online and print it out on paper on such scale it will be 1:8 to the original airplane.
Cut the building plan in sectors and start to cut balsa wood in shape it on the building plan.
I used 5x5 balsa for inner structure, 2mm balsa for sides, and 3mm balsa with some harder wood reinforcements for rudder and elevator.
Step 2: Fuselage
Rear fuselage is only from balsa, as front fuselage including motor mount needs to have some stronger parts, like wing mounts, sides, firewall plate.
As I build it from a random building plan, I used my feelings on how strong which part must be. Just follow the outer dimensions and help yourself with my photos as suggestion how to shape parts.
I wanted to have the wing from one piece, that's why the fuselage must be opened on top.
The part above the wing is attached to the wing with small magnets, as for the wing it is screwed to the fuselage with 2 M6 nylon screws.
Don't forget the pilot's seat :)
The one on the photo is too big, so I got a smaller one later.
Step 3: Wing Ribs
For profile I used Klark Y. You can find the DXF file to cut the ribs from balsa, or just to print it out for shape.
I went to a local cnc shop and got 2 profiles water cut, so I could screw in between 2mm balsa sheets, cut and sand around the aluminum reference sides. This way you can make ribs very fast and accurate.
Step 4: Wing
The best thing about this airplane is the flat wing. No V shaped angle in the middle. This makes it easy to make and very strong.
I used 5x5 and 10x3 hard wood sticks 1m long. On the sides I made edges from 3mm light plywood. In front there is 10mm balsa sanded as the profile shape.
Wing is partially covered with 1,5mm balsa making a D-box structure in front and a strong rear edge.
Use white wood glue, as it is the strongest. Fast CA glue is good just for fast placement, but wood glue sticks way better.
Don't forget to insert balsa blocks in the central part where screws for fixing the wing are placed.
Step 5: Aileron
Cut ailerons from the wing and cover the sides of the opening and aileron with 1,5mm balsa.
Don't forget to make holders for servo motors.
Step 6: Motor Cover
Motor cover is made from fiberglass from a simplified plastic mold. I milled the its shape it and vacuum the heated plastic sheet over it. The plastic can then be used as mold for fiberglass.
Step 7: Cover Film and Paint
Whole airplane is covered in Oratex, a special covering material that you can find in most model shops.
It is applied with a hot iron on about 120°C
Markings are than painted on top of it with 2K paint, since it needs to be methanol resistant. If you want to make the airplane electric, you don't need to use special paint resistant to chemicals.
Step 8: Make It Ready to Fly
Install the servos. Mini servos are good enough, but I suggest metal geared ones.
I used 4 stroke 5ccm ASP nitro engine. I was not bad, but I had some problems starting it fast at competitions, so I later replaced it with SAITO FA-30 S (H). This is a brilliant engine, works just perfect. For propeller I used Master airscrew 10x4. It runs perfect with methanol fuel + 18% percent synthetic oil and about 16% nitromethane.
Landing gear was first built from 2 and 3mm steel wire. After some combat rounds I crashed it and later used a composite one. Wheels are 80mm in diameter.
Fuel tank 110ml is more than enough for 10min flights.
Step 9: Details
Don't forget to make it look real!
Install a pilot, make some machine guns and wing wires. The pilot also needs a scarf, as it looks very cool when it flies.
Step 10: Test Flight
After many flights I have to say it flies very good! Even thou the first takeoff was not perfect as you can see in the video :)
As many WWI airplanes it needs both rudder and ailerons to make nice smooth turns.
Don't forget to set up center of gravity at about 1/3 from leading edge of the wing.
Thanks for checking out, If you have any other questions leave a comment :)
Participated in the
Make It Fly Challenge