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.

Here's some more.

The complete "Revolution 3D"

And of course the awesome BP21 brushess outrunner motor from www.balsapr.com

If you havent tried one of these. I highly recommend them. $26 bucks for a good outrunner motor.

And the landing gear set-up. Also note the mesquito on the wing, trying in vain to suck the blood out of my hot little plane.

Looks good! Are you going to make plans available?

what is the final AUW?

Sorry fella's ...There aren't any plans. Like I said I just grabbed some foam and started cutting. I didnt make any plans for it, because I wanted a one of a kind custom plane. I wanted something no one else has. Thats part of the fun of scratch-building. Bear in mind that this thread is entitled "scratch-building". Im trying to get you guys interested in designing your own planes instead of always looking for plans.

For those of you that have scratch built your own designs, please post them up on this thread. I'd like this to be a scratch-built design thread.

For those of you that havent tried scratch-building, go get some foam and start cutting.

I dont know what AUW is. I have GOT to get a scale. Its just a rough guess, but Id say its probably around 9-10oz. A little on the heavy side for my tastes, but considering its all 6mm depron, thats not to bad.

The BP21 motor puts out 11.3oz of thrust on a 2cell lipo. With a 2cell lipo, it will hover right at about 3/4 throttle, and pull out slowly on the last 1/4. I'm gonna get a 3cell to fly it on, should hover right at about 1/2 with a 3cell.

This thing is a hover eating monster. IT LOVES to hover. It will just hang there like its on a string.

For those of you interested in scratch-building, and want to know where to start. Ill post some dimensions once I measure it. You can pretty much shape it however you like, and it should fly as long as you keep the measurements the same.

I hope this inspires you all to start building, and Im looking forward to seeing what pops up in this thread!

Good idea BD. Been scratch building for about a hundred yrs. The synthetics, Depron, carbon fibre etc. make experimenting a lot easier. This is made from 3mm depron, braced up with carbon spars, leading edges made from a rod split down the centre to make two half round leading edge pieces. Put an Exacto blade across the end dead centre and hit it a rap and it will split like a log. once it starts, the blade will push easily end to end. Got the three view drawing from a Russian website that has the best I've found.I'll send the site if you like. Blew the drawing up multiplying 6 times with a calculator to come out with a 22 in. wingspan. Power is a Gobrushless CD Rom motor. More than enough to pick it straight up.

Yeah, now thats what Im talking about. That is cool. One of the guys here built something simular, never could get it to land vertically though. As soon as it touched down, it wanted to torque roll and tip over.

Ive already got an idea for my next scratch-build. There are so many basketball goals in our local gym (6 to be exact), we keep running into them all the time. So I figured I would make a flying basketball...Its gonna be neat if I can pull it off. Ill post pics of it when its finished. The design I have.....well, I think I might even be able to fly it through the net.

Too cool, looks good. Hope to see it tonight. Love to see it fly outside also. You may have given me some inspiration to try and scratch build one, also, would like to have one for outside flying . Keep up the good work. the airbrushing looks cool. Share the stoke Bill

Well, the first indoor flights went surprisingly well. The plane flew really smoothly inside. I had a bum reciever though which caused a few problems, but the plane flys really well. Bill has a couple of sub 5oz planes, and I flew both his shocky yak and his shocky extra. Both of those planes are incredible. Their extreme light weight really makes them fly great.

I love to scratch build experimental planes..... Sometimes I wish I had the paitence to draw it on paper first, so I can duplicate it.... but Im always too anxious to fly it

Anyway, heres a few...

the last 2 planes on the end have "gforce" wings they both fly awesome, I made the red one with the stripes on the wings for my dad to replace his tribute

bdavision,
I bought one of these:
"With a huge 30 lb capacity and precision 0.1oz readability, the LS-30 is designed for weighing both small letters and large boxes. Great for the office or kitchen"
Got it for $13.50 on Ebay from "saveonscales". They sell all kinds of scales on Ebay.
Runs on a 9V battery or charger, which is included!
Shuts off is automatic after a few mins so you don't run the battery down.
Love it!

I really like that P-38 Lightning looking one...can ya fly it indoors or is it strictly an outdoor plane?

Is that canard one that Burt Rutan design? Hows it fly?

The canard plane was based on burt rutan's Long EZ.... but mostly came out of my own head and spare parts. I had tried to make a flying wing that didnt work out, and that became the EZs wing. the canopy is from the remains of an old skylark 56 kit, the rest is just scrap depron. It was hard to get the balance dialed in, but once I did, it was incredibly stable and mauverable... Unfortunatly I got too crazy with it and nosed it in at near full speed.... its the only time in my flying career Ive had to make 2 trips to the crash zone to get all the pieces.... But I'd love to make another one.

The p-38 lookin one was also pretty fast, and flew nicely, but was fragile, and got heavy from repairs, then the motor burned up..... but fun while it lasted both definitly outside planes. you might be able to get away with the foamies indoors, but my lightest plane weighs in at 12oz, so itd be pushin it. It seems like its always windy here, and I dont have a gym to fly in, so the extra weight kinda helps...

Just witnessed the Revolution 3d plane fly outside and it fly's beautiful. it resembles a pattern plane to the fullest. The rolls are responsive and axle. Tracks straight. He extended the nose a few inch's , which looks even better and only adds to the performance. There is some flex in the wings , but not bad considering it weighs around 10 oz's. It looks like a great fun plane to fly and maybe it will inspire more people to scratch build. Thanks Bryan and keep up the good work. Bill

Yup. Bill and I went flying a few hours ago just before sunset. The Revolution3D is flying great. I think Ill probably add another carbon spar to the wing to stiffen it up a tad. The longer nose makes a good difference. Allows me to balance it out using lighter lipos, and makes the plane look more "pattern" like.

It tracks like its on rails. I think Bill and I were both amazed at the planes PERFECT centering. If you roll it, when you release aileron input, the plane stops DEAD ON. Its like WHAM....it just sticks right at that attitude as if the wing tips had brakes.
It does REAL nice stall turns. Pulls up smoothly to vertical, tracks perfectly through the nose over, and comes down the backside slow and smooth easily allowing you to time the exit to the right spot.

It doesnt seem to exhibit any coupling between rudder and aileron. Flat turns are nice and flat. We also finally weighed the thing...10.4oz with battery. Not bad for a plane thats larger than a formosa.

That sounds really heavy, but its got such a large wing area, that it floats really well. Easy to slow it down. Indoor flight is no problem, but it excels outdoors.

Well, Ive been flying this revolution 3D for a while....Its a superb plane. Best flying outdoor foam plane Ive ever had. And the most durable.

Ive smacked it in a couple of times trying different stuff. I nose plowed it in during a full throttle inverted low pass through the grass. All it did was pop the motor mount loose.

Unfortunatly it met its untimely demise yesterday. During a spin. It layed down its 2 of a kind, and was beaten by a powerline's Full house.

But...

The revolution legacy will live on in its new and improved children. Coming soon....the Revolution II

Ill post pics soon.

So have any of you out there finished your scratch-built yet...and if so post pics!!!!