Projects Derek's Scratch Built 74" 3D Plane

[Derek]

Two years ago, I think, Tony helped me choose a BIG motor for a project that I was working on...it didn't go so well, lol....long story.

So, I still had this Tacon Bigfoot 160 motor and nothing to put it on (Here is the link to the motor if you are curious: http://www.hobbypartz.com/96m608-bigfoot160-5335-245kv.html).

I decided to build a rather large 3D plane. I've loosely modeled my build after the Edge 540 and Extra 330. The plane doesn't have a name yet but i'll come up with something. Anyway...I used 3/4" insulation foamboard from my local home improvement store (a mere 2 minute drive from my house, lol) and I used a bit of 1/8" plywood, here and there for strength and rigidity. I bought the landing gear from my local hobby shop. I believe they are from a 68" Sbach but they look pretty good under my plane. The motor mount and firewall are all one piece, made from 1/8" plywood. I wish I still had pics of the firewall before I glued it in. It was a real piece of work.

Anyway, I have some very strong servos that I'll be using. One servo for each aileron, of course. One servo for the rudder on a pull/pull setup. I'll be using two servos, one for each elevator half and I'll have those two servos on their own, individual, channels with a tx mix. The Tacon Bigfoot motor is rated up to 14S lipo packs. I'll be running a 12S setup with a Caslte ICE 120HV ESC and an rx pack. I'm still undecided on the prop to use. I have an 18x8 APC prop but I'm wondering if that's too much prop....perhaps something in the 15" range (Tony, I could use any advice that you could offer).

I'm anticipating the AUW to be a bit more than 15lbs. In the picture below, you can see that the plane is white. I used Duck Tape. Undoubtedly, the Duck Tape is heavier than my usual colored packing tape but the white packing tape just didn't hide the green foamboard very well, at all. So, I used the Duck Tape. I'm also hoping that, in the unfortunate event of a crash, the Duck Tape will help hold the pieces together a bit and maybe there will be less cleanup, lol. As I said, the plane is white for now. I will be adding some blue, black, and silver because the wheel pants that came with the landing gear have white, black, blue, and silver on them. It just seemed easy enough to color the plane to match the cool looking wheel pants.

So...here's a pic and I'll post more updates as I progress:

 

[Tony]

Ah yes, the 20' wing that just didn't work after 2 years of work. I was sad to see that thing not do so well.

With that said, that fuse is HUGE! For those that don't remember, that motor on the front is the size of a Mt. Dew can! That fuse has to be 8" across! MASSIVE! lol.

As for props, those size 3D planes are using an 18x8 to a 20x10 prop. Granted this is for gas powered engines, but they make APC props that size as well for electric motors. So I think the 18x8 that you have will work out just fine. Just remember, the rule of thumb is, for 3D you want your pitch to be half your length. But for regular flying, you should have a bit more pitch. I'm using a 13x8 on my 540 for regular flying, but it asks for a 12x6 for 3D.

Either way, as long as you put a rounded nose piece on that plane, I think the 18x8 will work just fine.

Now put the wings on it, we need to see the plane!!!

 

[Derek]

Yeah, I was bummed that the 20' wing didn't do so well, too. But...moving on, we have a 74" wing to deal with now

Yes, this motor is massive...no doubt! I just measured the fuselage, across, and you were close, Tony. It's 9" across. Originally, I hadn't planned on a cowl but I quickly realized that this plane is just going to "HAVE" to have a cowl of some sort because of the width being so much. As I look at the plane, as it sits now, I can see that the nose is just too wide and, in my opinion, the fuselage is too tall, as well...but I'm no pro builder, lol.

I do have a 20x10 APC prop, too. As you can imagine, my first few flight attempts will be far from any sort of 3D. My hopes are that I can get 5-10 flights and landings, just doing circuits. If the plane survives those flight attempts, perhaps we'll try a loop and roll, lol.

I am going to cut off the rudder and make a new one. In my eyes, I'm noticing that the rudder is just too short. Yes, it would probably function just fine, as it is, but it just doesn't look right. I do have the wings made. They are not covered yet but the plane looks pretty awesome with the wings attached. I'll get a pic or maybe a video walk-around posted with the wings attached.

Thanks for stopping by!

 

[RandyDSok]

I was thinking the tail looked a little short also and perhaps the elevator a little narrow but it's hard to get a perspective from the picture also...

It may be too late to suggest since you've got the general form of the fuse already laid out... but perhaps on the next one look at hobby shops like Extreme Flight and 3D Hobby Shop ( same company now, just different divisions ) and pick a cowl from one of their many planes that you like... then do your design work around that. They also carry spare landing gear and other parts for their ARF's

Looks like it'll be a fun one no matter what direction you take it now.

 

[Derek]

Thanks Randy! Remaking the rudder will be easy. I think the elevator is pretty close to being right. If not, perhaps I can just compensate with more throw.

 

[Derek]

Here are two pics that I just took. I slapped the wings onto the plane so that I could show you the wings "on" the plane, as per Tony's request above. I need to get some more white Duck Tape so that I can finish the white on the wings and then add a bit of black, silver, and blue to match the wheel pants. I've also decided to add a cowl, for a couple of reasons:

1. It's a 3D plane...it needs a cowl, lol
2. There is so much material aft of the CG, I just think that the monster motor needs to be moved forward more....so, a stand off is gonna have to be built
3. If I don't put a cowl on this plane, I think Tony would just freak out, lmao. (sorry bro, lol)

....more to come...

 

[D.O.G.]

Wow Derek, that bird is huge. When you're done with the build, you need to take me for a ride in it. Lol. Looks great! Keep the pics coming on the build.

 

[Derek]

Sorry DOG...no rides on my plane....safety first, lol.

 

[Derek]

I'm adding the white to the wings and a part of the upper nose (it's a removable panel). I want to put the wings on the plane and try to decide on a color scheme. Since the wheel pants are white, blue, silver, and black...those are my colors that I'll be using. I just need to decide what colors go where and in what shape or orientation.

...more to come.

 

[Derek]

...a bit of progress...

 

[EyeStation]

It is always amazing to see what you put into your projects Derek. Outstanding job Again! The wing profile was a work of art, do you have any shots of you scoring and forming it? Curious on your choice of winglets and other surface additions.
I also see a bunch of shiny stuff on the wall behind it, specifically that wing in the lowest perch. I don't believe I saw that in the air yet.

I've been lurkin here still, but it took your build to get me over to the keyboard.

 

[Derek]

Thanks Dave! It's been a rollercoaster of a project.

The wing profile came out pretty well. It seems to be pretty symmetrical between the two wings. I am very bad about NOT documenting my build progress so, unfortunately, I don't have any pic of how the wing was scored and formed. In fact, these wings were formed last Summer. I honestly don't remember how I got the airfoil on top and bottom. I do remember how I scored the inner surface of the wing. I simply marked out a bunch of "bend lines" with a Sharpie marker to allow the foam to bend (this stuff is quite rigid in small sections). Then I covered the outter skin with clear packing tape to help hold the foam together after the score cuts were made. I used a Roto-Zip tool to make the scored lines. This foam is 3/4" thick. I set the cutting bit, in the Roto-Zip, to cut 3/8" into the foam. Once all these lines were scored, the foam didn't bend as much as I had hoped. So, I got out a new and sharp utility knife and cut some foam away from both sides of each of the scored lines (you can see this angled cuts in the wing tips in the last video). After these angled cuts were made, the foam would bend with ease and made it pretty simple to form around the wing spar tube.

Like I said, I'm lousy at documenting my builds. It would probably prove beneficial if I would take some more pics during the build so that I could show off what I'm doing, as well as others could give me their input along the way.

You said that you see a bunch of shiny stuff on the wall behind it. I think you are talking about another scratch build that I've done. Again, lousy at documentation, lol. That plane is a scratch built "Weston UK Velocity 50" electric version. Do a Google Search for that plane and you'll likely see my UK buddy, Deano, flying his kit. They are nitro powered...fast...loud...and awesome!!! I spoke with him and he was kind enough to send me a lot of various measurements. Then I built one, lol. I'll get some info posted here, at RCH, on that wing soon since you seem interested. And no...it's not been flown yet. The weather here is absolute crap....25mph+ winds, rain....just ugly.

So...keep your "Eye" on the forum, Dave. I'll get some more info posted about my 3D plane as I get more progress done and I'll get some info posted about my scratch built Velocity 50.

 

[Derek]

I was able to spend some time on the fuselage tonight. I've got a Spektrum AR8000 bound to my DX8. I've got the profile set up for dual elevators and dual ailerons. The dual elevators and rudder are working properly and in the right directions. I added some blue and silver to the fuselage and this is how the fuselage is looking now



I just need to finish up the aileron wiring, make a few extensions, program the Castle ICE 160HV, add some blue and silver to the top of the wings and some black checker to the bottom of the wings, mount the motor and prop, and then we are checking for the CG. Maiden flight is coming quick, lol.

 

[Derek]

Re: Derek's Scratch Built 74" 3D Plane

I've done some more work on the 74" unnamed plane. It's definitely coming along. Instead of going through all the work to buy the aluminum and then bending it to make a 3 piece adjustable motor mount, I decided to go "cheap" and simply used two 7" long pieces of 2" x 4" pine. I have an ample supply of boards left over from other projects and I figured that the 2x4's would set the motor a bit more forward and give a bit more nose weight. I'll surely need to fabricate a cowl of some sort but we'll talk about that later. I just took the plane into the driveway for a few pics......and naturally my lil girl couldn't resist a photo op, lol.






Left to do:

Add coloring to the main wings, top and bottom
Add black stripes to the underside of horizontal stab
Add connectors to the aileron servo wires
Add ailerons and linkages
Build cowl
Add battery mount (for the flight packs and rx pack)
Check CG and make necessary adjustments for balance

I think that's about it.

- - - Updated - - -

...two more pics...

 

[D.O.G.]

Re: Derek's Scratch Built 74" 3D Plane

I've done some more work on the 74" unnamed plane. It's definitely coming along. Instead of going through all the work to buy the aluminum and then bending it to make a 3 piece adjustable motor mount, I decided to go "cheap" and simply used two 7" long pieces of 2" x 4" pine. I have an ample supply of boards left over from other projects and I figured that the 2x4's would set the motor a bit more forward and give a bit more nose weight. I'll surely need to fabricate a cowl of some sort but we'll talk about that later. I just took the plane into the driveway for a few pics......and naturally my lil girl couldn't resist a photo op, lol.

View attachment 15874
View attachment 15875
View attachment 15876


Left to do:

Add coloring to the main wings, top and bottom
Add black stripes to the underside of horizontal stab
Add connectors to the aileron servo wires
Add ailerons and linkages
Build cowl
Add battery mount (for the flight packs and rx pack)
Check CG and make necessary adjustments for balance

I think that's about it.

- - - Updated - - -

...two more pics...

View attachment 15878

View attachment 15879

Good lord Derek. That plane looks great and a lot bigger then it looked on your bench when you were building it. How much do you charge for a ride? Man o man you must make a video of your first flight. Your munchkin is not a munchkin no more. She's getting big.

 

[Derek]

Thanks DOG! Yeah....it's definitely looking good! There are some things that I wish I had done differently but it's too late to make those changes, lol. Nonetheless, I'm very happy with it and I think it will get off the ground....at least once, lol. I'll have my Dad on hand to run a camera for me for the maiden attempt.....and yes...my lil one is getting quite big. She's talking more and more each week.

 

[Derek]

I just added some black stripes to the underside of the main wings. I may add a few small stripes to the underside of the elevator halves so that they match the main wings. I added some blue and silver striping to the tops of the main wings....now they match the colors of the wheel pants, fuselage, and horizontal stab. Cool!

I also got done adding the ailerons and linkages. I cut my aileron servo extensions to length and added a servo connector. I even got the "travel", "dual rates", and "expo" set up (of course, these are all subject to change). I am now able to move the two ailerons, the two elevator halves, and the rudder and they are all moving in the correct directions.

Now, I need to build a cowl and then place the batteries in the nose at a "guess-timated" location and then check the CoG. I'll need to come up with some kind of battery tray so that I can Velcro the batteries into place (the two 6S flight packs and the rx pack).

After that's done....I'm thinking this plane will be done (two years in the making, lol).

 

[trainrider06]

Wow! Been a few weeks since I've been able to check this project, really looks great Derek!
There is always that relief and excitement when a project comes to an end but kinda a sadness too isn't there knowing the project is finished at least for me, because I really enjoy the build as much as the flights.

 

[Derek]

I have to totally agree with you. I enjoy the build as much as I enjoy flying. I might even enjoy "the build' more than "the flight". I think that's why I always seem to have 6-7 projects going at the same time, lol. I have an active imagination that just won't quit. I'll PM you a link to a video to another massive project that I attempted last year.

Thanks for following my progress! I hope we can all be rewarded by a successful maiden.

 

[trainrider06]

I have to totally agree with you. I enjoy the build as much as I enjoy flying. I might even enjoy "the build' more than "the flight". I think that's why I always seem to have 6-7 projects going at the same time, lol. I have an active imagination that just won't quit. I'll PM you a link to a video to another massive project that I attempted last year.

Thanks for following my progress! I hope we can all be rewarded by a successful maiden.

Please do! I enjoy your builds! I need some advice on an FPV racer too! I've seen these ones on eBay but not quite sure which would be a good one to start out with....