Derek's Scratch Built 74" 3D Plane

[Derek]

Thanks very much, DOG! I'm pretty happy with how the plane is coming along. I sure do hope it flies....at least once, lol.

[Vipertech13]

Aughhhh! Derek you are keeping me on the "EDGE" of my seat with this plane and the Velocity! Cannot wait to see you put these birds up!
Makes me think of the quote from the movie The Sand lot " You're KILLING ME Smalls"

[Derek]

Lol, thanks Gerald! Yeah, these two projects have been fun. Hopefully the fly....at least once lol.

The movie "Sandlot"....great movie!!!

[Derek]

I probably know the answer to this but, as always, I wanted to come to you guys for your opinions and thoughts (always valuable to me)

So....this project plane is nearing completion, as far as the build. I have bound an AR8000 rx (thanks Lee) to my DX8. I have it set up for dual ailerons and dual ailerons. At this point in the build, the dual ailerons and rudder are working perfectly and evenly (as well as my eyes can tell). I'll set up the dual ailerons once I finish the new wiring and extensions.

Anyway...my question is about the center of gravity. This plane is large....74" wingspan....74" long (from rudder tip to the nose). I'm assuming a "CG Check" can be done just like I do my smaller planes. Obviously at the wing spar but this plane is large. I'm not sure that I can just put my fingertips under the wing and easily pick the plane up and check the CG. I could probably make up a stand of some sort, similar to a saw horse, that can be placed under the plane, at the wing spar, and check for the CG that way.

What do you guys think/suggest?

[Derek]

I spent some time tonight on the plane. Here is how the fuselage is looking now

20160411_042711.jpg (138.53 KiB) Viewed 4312 times

Now I just need to finish up the aileron wiring, then attach the wings, then add some blue and silver to the top of the wing and some black lines or checker to the underside of the wing.

[Graham Lawrie]

That looks awesome Derek:) cant wait for the maiden:)

[pvolcko]

For a large plane like this I'd go with a CG cradle or I've seen some people rig up a way to hang it on wires hooked up to the cg test point on each wing. The point is to have the holding point be much closer to the fuselage (even right next to the fuselage) rather than out at the wing tips. A lot of times the wing tube can be used as the CG point, depending on the design of the model.

[Derek]

I have to agree with you, Paul! A CG cradle is probably the way to go.

I sure hope this sucker flies, at least once, lol.

[DOG]

Hey Derek. That plane is looking sharp my friend. Don't worry Derek, we all have faith in you so that plane will FLY!! Video please of first maiden.

[Derek]

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.

front right of the plane, shows the 2x4's for the motor mount, motor mounted, prop added

plane front right.jpg (105.14 KiB) Viewed 4270 times

plane rear right.jpg (103.4 KiB) Viewed 4270 times

My awesome helper

plane with Makayla.jpg (101.45 KiB) Viewed 4270 times

my wife and munchkin

plane Jordan Makayla.jpg (93.39 KiB) Viewed 4270 times

plane me.jpg (98.78 KiB) Viewed 4270 times

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.

[Stambo]

Wow, that thing is sure is BIG.
Should be really easy to see in the sky.
Hurry up and finish it, I wanna see it fly.

[DOG]

Wow, that thing is sure is BIG.
Should be really easy to see in the sky.
Hurry up and finish it, I wanna see it fly.

I want to go for a ride!

[Graham Lawrie]

Nice one Derek:) The unnamed plane has to be "Makayla 1" surely:)

[Derek]

Thanks Graham! Actually, I have a new plane in mind that I will be naming "The Makayla". I just need to get a few other projects finished before I can start building it.

[Derek]

Wow, that thing is sure is BIG.
Should be really easy to see in the sky.
Hurry up and finish it, I wanna see it fly.

Yeah man...it's definitely big. With the wings on, I've had to pick it up and flip it over a few times and move it around....I think it's a bit heavier than I had anticipated. Not sure. I do have a scale that measures up to 50lbs. When I get it all done, and batteries installed, I'll have to get an AUW. I will be in no hurry to do any loops or rolls, nor anything beyond that, but if I can get this plane off the ground, fly a few circuits, and land with zero to minimal damage...that will be a success!

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 ( almost two years in the making, lol).

[Derek]

IT.....IS......ALIVE!!!!!!

https://youtu.be/Hq2uw5F9Tjk

[DOG]

Awesome! You did a good job Derek Good luck on your first flight.

[Vipertech13]

NICE! Massive throws on the control surfaces! That motor has some serious torque!

[Derek]

NICE! Massive throws on the control surfaces! That motor has some serious torque!

Thanks Gerald! I left the control surface throws at 100% with zero Expo so that the movement could be seen in the video easier. These will be turned down slightly and expo will be added before the maiden flight. As for the torque....no doubt this monster motor has torque. This motor has an outside diameter of 62.8mm....length of 64mm....8mm motor shaft....245kv and up to 2700 watts on 14S. I'm running a 12S set up. Unfortunately, I have no way of measuring the wattage....unless it can be displayed in the Castle ESC Logging.

[cml001]

Nice..