Recently, I've been wanting to scratch build a new foamy 3D plane. So I looked at all the foam planes I have, and picked out the things I liked on each of them. I wrote them down on a sheet of paper, and tried to implement them into my scratch build design. I sketched the design on a piece of notebook paper during my lunch hour at work.


I liked the Ultimate biplanes huge rudder, so I decided to use the Ultimate's rudder shape.
I liked the F3A shockflyers swept back pattern shaped wing, so I used it, and swept the wingtips out more.
I liked the landing gear set-up on the formosa, so I decided to make what is probably the only foamy with the gear mounted on the wings with no part of the structure contacting the fuselage.
Ive often wondered if the square rounded nose of the Yak was part of what makes it fly so well, so I tossed that in for good measure. I liked the construction techniques of the Shockflyers, so I decided to make "construction" much like a shocky.

NO plans. I just grabbed the depron, and a exacto and started cutting. I used a t-square to make sure I got everything straight and measured right. My dad was watching me with concern, as he didnt think you could just cut and get anything right.

Now I wanted to build my new plane out of 6mm depron. I like the thicker stuff, because it is MUCH more durable. The problem with this is weight. Going from 3mm to 6mm will double the weight of the foam used.

This required some brainstorming to come up with some unorthodox means of "lightening" up the airframe. After much thinking....almost so hard it made my head hurt. I was thinking how can I take foam off without affecting structural integrity.
The question came to mind..."What part of the airframe doesnt need to be strong?" The obvious answer being the control surfaces. The control surfaces on a foamy dont bear any weight, dont have any strong forces applied like landing, twist, etc.

With this in mind I set about trying to figure out how to remove foam without destroying the surfaces. I punched 1/2" holes staggered along a piece of foam. It reduced the weight a little, but the piece didnt lose any of its strength. Now the question was how to cover it without adding too much weight. I just use packing tape. Simple and lightweight. Unfortunatly I dont have a scale, but the pile of foam dots that I had in the end, weighed more than a 371 servo.

Well, that lightened it up a bit. What else could I do to it. How about eliminating ALL reinforcement in the tail, and NO carbon fiber wing struts.
Since Im using 6mm depron, the stiffness of the foam is enough to keep the tail from flexing, and by simply using the shockflyer design of carbon strip leading and trailing edges, the wing will be stiff enough.
I went with Bluebird BMS-303 servo's for elevator and rudder. These little 3.6g servos are lightweight wonders.
I then used a GWS 4ch pico reciever. Cut that plastic case off of it to further reduce its weight, and glue it to the plane with some hot glue.

I wanted the battery to hang from underneath the nose. I dont like the shockflyers design of putting the battery through the slot in the fuselage. Every hole you put in the fuselage, is one more added spot where the fuse will fail structurally in a hard hit. With the battery mounted up front, it takes care of the CG problems I would have encountered with the short nose vs long tail. Plus I dont have to have a big gaping hole in the middle of the fuselage.

A BP21 brushess motor was mounted to the nose on a plywood mount.

Ive always liked the professional looking airbrushed paint jobs that the planes from the eTOC and compositearf.com have. I think they look HOT. Well.....as you figured, I airbrushed the whole plane.
The paints I used were Model Master Acryl Water based paints. These paints wont melt the foam, and are already thinned down enough to spray through a cheapo airbrush.

I used Model Master Silver for the nose and leading edges of the wing
Model Master Flat black for the charcoal look of the wing, and fuselage. Then I flicked some of the black on for the speckle.
Pactra Enamel Competition Orange for the ailerons and tail.
Model Master Flat White for the highlights.
Sharpie markers for the fine details.

Now that the plane was all built I was of course concerned if all this work was for naught if it didnt fly.

I was kinda scared to try to fly it. After all this was almost 2 weeks of pain staking fine detailed work....if it didnt fly right and crashed....I was hosed....and going to be really $*&%$ off.

I took the plane out back behind my house, and gave it some throttle. Held it out straight up, and trimmed it out for hover. I let go, and watched as my GORGEOUS scratch built plane hovered almost handsfree. It was EXTREMELY stable. Virtually NO inputs to keep it nose up.

It was time to try some flying. I gave it a little down elevator to get the nose down. It smoothly nosed over and into forward flight. I did a aileron turn, and it smoothly came around, NO loss of altitude. As it came by, I goosed the throttle and pointed the nose up, doing a perfect slow 20ft loop. Turned it around flat on rudder, and gave it aileron for a roll. It rolled over VERY smoothly, no elevator or rudder needed. Roll rate was perfect, not to fast, and sharp and crisp. No overroll exhibited.
Now came the fun part. Landing...

I slowed it down, and jacked the nose up. I was expecting the charectoristic tip stall exhibited in most foamies. Nothing, It just stayed dead level no matter how slow I got it. NO aileron input needed to keep the wings level. Absolutly fantastic.

I was also concerned about the landing gear. I figured that anything other than a smooth landing would shove the landing gear through the wing. I didnt know if my new design was going to work...It certainly didnt seem sturdy. I figured I would have to really finesse the landing. NO problem.

Since the landing gear dont have any braces, they are very springy and flexible. As it touches down any shock is simply transferred, and just flexes the gear instead of popping anything loose. I tryed a couple more landings. Even catching the gear in the grass and nosing over the plane, didnt result in ANY damage. I KNOW for a fact that if that had happened with my shockflyers, I would have been gluing the bottom of the fuse back together.

Anyway, here's the pics of my new wonderplane. I call it the "Revolution 3D"
Enjoy

And if you havent tryed scratch-building a plane yet.....GO FOR IT.