FT 3D PRO(file) depron conversion

Hello everybody. This is a presentation of my first "almost own" design, so please be reasonable with your comments 

The background:
1. Light = cheap.
2. I live in a country where 1,2m x 0,8m depron sheet costs less than 10$. EPP foam is almost twice that, and DTFB/FTFB is not available by any means.
3. Carbon rods of appropriate size are $0,5-$1 per 1m.
4. I've recently build some light planes using depron foam (few Baby Blenders, Twin Twirl from the original plans) and loved the idea.
5. I've already build FT 3D following the original plans (modified for 6mm depron) and liked it very much. Unfortunatelly it's not flyable anymore (car's inside on a warm, sunny day is not the best place to store planes put together with hot glue).

The goal was to expand my hangar with a plane that will 1. allow me to improve my flying skills, especially in the aerobatics, and 2. be able to fly in moderate winds better than anything I currently have. FT 3D seems to fit this criteria pretty well, but the complexity and workload involved in building one made me looking for something else. I turned my attention to profile planes, which are usually much easier to build and maintain; but I wasn't able to find any project that would catch my attention. Currently, most planes are designed for EPP; which is not bad, but I just happen to not like it at all. The choice of KIT/ARF planes available on the market is the same. I was almost ready to buy one anyway; when the idea came to me to use original FT 3D plans to build my own profile plane. The research was quickly re-oriented from "what" to "how"; but that wasn't any easier. I didn't find any good build tips/videos for depron planes (everybody seems to forget this wonderful material ever existed); but I did found a great example of exactly what I had in mind: E-flite Extra 260 3D Profile. It may not be the most popular 3D profile plane in the world; but it's build beautifully with all the materials I have readily available and using building techniques I'd love to learn.

That's how FT 3D "PRO(file)" was born.

The build process took me about a week; working several hours during one weekend and then approx. an hour every evening. On the last thursday, she was finally ready for the maiden flight. Let me share a video relation from this event:

The video above shows two of the very first flights of this plane. Since I'm not an aerobatic pilot by any means, I was pretty nervous. The plane's control surfaces have max deflections of approx. 45 degrees; but I've limited them to 55% and dialed in 40% expo. Surely enough, the plane was still touchy; much more than enough to make me scared a lot. I've managed to land her down safely, and before the next flight, I reduced the deflections further down to 40% and increased expo to 50%. As seen above, the second flight went fine as well.

Here are some stills from the video:

The launch for maiden flight was very easy and very uneverntful

A couple of high passes while I'm getting used to very crisp and very sensitive controls

Then, few more low passes to watch the beauty make her way trough the air with no effort and no bad tendencies whatsoever

And finally a successful landing after a bit exhausting, but very satisfying flight.

After a couple of flights I started to feel comfortable enough to try out the "ultimate 3D plane test": hovering. As I said before, I'm actually not the right person to do that; and the hovering is the only 3D aerobatics I have any idea how to perform. But the plane did not let me down. Here what my attempts look like:

Still images don't quite show that; but here they are anyway:

There was still some wind during the first attempts; I needed to compensate for that in the early flights

Staying at the field till late evening rewarded me with completely still air and some very nice views

Not that bad, right? In fact, way better than anything I could ever do on my original FT 3D. I know my skills probably improoved since then; but I was usually flying planes like FT Simple Storch, Twin Twirl or Baby Blender - not exactly a very aerobatic ones. I'm sure this plane will lead me trough the process of learning 3D aerobatics with calm and confidence I couldn't even imagine when I started to build it.

Having the "hovering test" passed (sort of), I've tried some other aerobatic trics. I even felt confident enough to swich to high rates (100% throw, 30% expo) for a moment. The plane's dynamic response scared me a lot again, but also made me smile like I never did for a very long time (at least when flying RC planes):

I have to admit, this particular day gave me one of the best looking videos and images I've ever contributed to make:

Unfortunatelly: the day light ended, the batteries died, and my kids demanded to go home immediatelly without exceptions. Thanks to that, I did not went pass the point of the ultimate "one more time" flight, and I still have this wonderful plane flyable and without even one scratch or dent. And I'm still hungry for more.

I already shared some info about the design and build process in the forum thread: FT 3D depron profile. If you want to know more details, please leave the comment with your questions; I'll be more than glad to answer. If the demant will arise, I will try to write a more detailed, build-like article.