Mini Scout (Big Wing Mod)

[Cpt_Tuco]

Hey guys, First post here.
I'm "New" in the DIY part of the hobby, i mean, i have a degree in electronics and a background in "Full Scale aviation", Just so I have a rough idea of what I can and can’t do before things go sideways.
I've already made a FT-EZ Glider to test my Glue Gun skills and i turned out OK, then I've made a Sparrow w/ Aileron Wings and a FT-Mustang (all scratch build), Both are ready but not maiden yet. And that's the problem. I live in a big city, like, a reeeaaly big city, like 20M+ people. And finding a great open field in the largest city in the southern hemisphere is a big hassle, parks are full, Eletric poles everywhere.
And thinking about that, i'm building a Mini Scout w/ a Bigger Wing.
i didn't change the Scale of the whole plane, i just made the wing span bigger, 900mm or ∼35.5 in , the cord is the same.
I know, its a HUGE increment from the original plan, and i realized that when i saw the span in comparison to the Fuselage.
The Vertical Stab is 20% taller ( i don't think that it will be enough ).
But that's the Plan. Mini Scout w/ High Aspect Wings, Flaperons, a 2205 engine w/ a 6x4 prop.
Yes i'am reinforcing the wings w/ spars.
The Goal is to fly Slow in tight spaces, the 2205 is the smallest engine ive got.
6x4 is too much for the engine ? ( RS2205 red bottom generic). i think i have a 5x5 prop somewhere. might test it too.
What u guys think about the setup ?
Any suggestions ?

 

[Michael9865]

Cool idea, are you going to add a carbon spar to strengthen the longer wing?

 

[Cpt_Tuco]

Cool idea, are you going to add a carbon spar to strengthen the longer wing?

Yeah, im planning to use bamboo skewers in the wing, one in 25% (35mm) of the cord from the leading edge, and the second 50% (70mm) from the LE. both glued in a slot on the bottom of the wing.
Maybe it will be Enough, the Scout Wing is a single layer of foam, reinforcement is mandatory in this project.
I've read somewhere here in the forums that Ironing the trailing edge makes it more durable, do u have tips on doing that ?

 

[RickHunter]

With a spar you should be okay. I would use strut brace on between the vertical and horizontal stabilizer if you increase those.

 

[Piotrsko]

Ironing the edges just makes the plastic foam bubbles collapse into a rigid solid. Yes it's stiffer, but not structural/load bearing stiffer, more like fly through a bush stiffer

 

[Cpt_Tuco]

With a spar you should be okay. I would use strut brace on between the vertical and horizontal stabilizer if you increase those.

Thanks for the feedback, I honestly didn't think about it.
But, Let’s see how it flies with the slightly bigger vertical stab and stock horizontal. If I need to make them bigger, I’ll add struts like u said. Bbq skewers ? lol

 

[Cpt_Tuco]

Ironing the edges just makes the plastic foam bubbles collapse into a rigid solid. Yes it's stiffer, but not structural/load bearing stiffer, more like fly through a bush

Do u recommend doin it? I’ll experiment on some scrap parts of foamboard and see how it goes.

 

[RickHunter]

Thanks for the feedback, I honestly didn't think about it.
But, Let’s see how it flies with the slightly bigger vertical stab and stock horizontal. If I need to make them bigger, I’ll add struts like u said. Bbq skewers ? lol

When needed, Bbq skewers are what I use on everthing but the monster builds. They work great.

 

[Shurik-1960]

The 2205 likes the 8040 propeller and the 2S battery for slow flights and 3S for piloting.BUT the flight weight of the model should be no more than 400-450 grams. I have 6 2205 engines on models : Cesna 150-2 models, Puff S- 1 model, Wing Vzhik- 2 models.

 

[Cpt_Tuco]

Update: I’ve assembled most of the fuselage. The 900 mm wing, even with two bamboo skewers, was still way too flexible and twisting a lot, so I decided to add two more skewers—one along the leading edge and another along the trailing edge—tying both wing halves together at the root. That made a huge difference in rigidity.

I embedded the skewers into the leading and trailing edges using something I stumbled upon by accident (though it’s probably a well-known trick here): I used the tip of a hot glue gun to melt the foamboard between the paper layers and open a channel for the skewer, then fixed it in place with hot glue. It worked surprisingly well.

And yeah, I didn’t do the scalloped details on the trailing edges because I wanted to keep this prototype more experimental and fast, but after seeing how stiff the wing is now, I think it’ll work out fine.

In hindsight, it might have been better to build a folded wing like the larger version. I compared it to the wing on my EZ Glider, and even without spars the Glider’s wing feels very rigid.

After New Year’s I’ll install the electronics and weigh everything to get a better idea of where things are going w/ the project.

That’s it for 2025.
Wishing everyone a great 2026.

More updates coming soon.

— Cpt_Tuco

 

[RickHunter]

Feliz Ano Novo. Bons voos.

 

[Cpt_Tuco]

Feliz Ano Novo. Bons voos.

Thanks!
Muito obrigado!

 

[Cpt_Tuco]

The 2205 likes the 8040 propeller and the 2S battery for slow flights and 3S for piloting.BUT the flight weight of the model should be no more than 400-450 grams. I have 6 2205 engines on models : Cesna 150-2 models, Puff S- 1 model, Wing Vzhik- 2 models.

I’ll run the 2205 2300kv on 3s w/ the 6x4E (Ecalc Shows 858g of thrust (full charge).
I wasn’t considering 2s but, simulating on Ecalc, a 8x4 prop on 2s as u said is showing 695g of Thrust, so ur spot on on the weight of the models.
On the other hand, 8x4 on 3s : 1200g of thrust w/ a power draw of 42.1A at max, i have a 50A rated Esc but it is on the mustang, for the Scout I’ll use a 30A Esc, so I’ll keep the 6x4 on 3s

Thanks Shurik

 

[Piotrsko]

Might want a spot of wider tape covering your spar skewers just to keep them in place. Yes I know they are glued in, but I might demonstrate delamination of the foam during flight leading to torn out pieces AND upward folded wings but perfectly attached fuse to wing joints.