The most INSANE RC Scrappy you will see...

[Taildragger]

It's physics, math, and engineering... and a lot of them!
Time for motivation pills!
I have spent the last week laying in bed at night, it's designing new parts, designing new suspension, designing new wings...
Basically I have been listening to podcasts and videos and it's really incredible to see Mike Patey's process when he came up with scrappy, and I want to kind of recreate his awesome plane, scrappy.
I'm going to most likely go to high sierra fly in this year (2022), and so I want to bring some epic planes (obviously). They need to be outrageous, like a highly detailed 1/4 scale cub, or a very functional Scrappy.
What makes Scrappy unique from other cubs in my opinion are 4 things: 1. The tubby, tall fuselage 2. the ability to adjust ride height on the fly 3. solar power for accessories and 4. The revolutionary new wing system witch utilizes P-STOL flaps in conjunction with a retractable double-slatted leading edge.
These are essentially the goals for this project.
How I plan to do these on the RC model
1. Modify a CAD model of a cub fuselage to better resemble Scrappy
2. Idk yet
3. This one is the fun one! I plan on putting real solar panels and lithium ion batteries in the wings, turning them into solar-powered power banks. After doing the math, I found that the amount of power the panels will make without battery assistance is enough to power up to four USB devices simultaneously.
4. Kinda just copying Mike's design. 3D printing likely to be involved.

Current CAD Model (Pic updated often):

 

[Ligbaer]

please build this one

 

[Musdang]

You could use the panels to power lights and such

 

[Hondo76251]

That'll be awesome!

I started on a "Scrappy" for the Bush Plane Challenge but never finished it (that was before scrappy was even flying) been watching all of Mike's videos for quite a while!

All of my parts have ended up repurposed in other projects now, its all up to you! 😂 gotta have a scrappy in this years BPC!

 

[Taildragger]

please build this one

Sure, but this build isn't going to start until late may and will be finished in august

You could use the panels to power lights and such

I plan to use 18650s to make it a power bank and possibly just be a free charging station at high sierra

 

[Musdang]

Sure, but this build isn't going to start until late may and will be finished in august

I plan to use 18650s to make it a power bank and possibly just be a free charging station at high sierra

I’m not sure an airplane can run Mac OS lol

 

[Beaver5150]

It's physics, math, and engineering... an a lot of them!
Time for motivation pills!
I have spent the last week laying in bed at night, it's designing new parts, designing new suspension, designing new wings...
Basically I have been listening to podcasts and videos and it's really incredible to see Mike Patey's process when he came up with scrappy, and I want to kind of recreate his awesome plane, scrappy.
I'm going to most likely go to high sierra fly in this year (2022), and so I want to bring some epic planes (obviously). They need to be outrageous, like a highly detailed 1/4 scale cub, or a very functional Scrappy.
What makes Scrappy unique from other cubs in my opinion are 4 things: 1. The tubby, tall fuselage 2. the ability to adjust ride height on the fly 3. solar power for accessories and 4. The revolutionary new wing system witch utilizes P-STOL flaps in conjunction with a retractable double-slatted leading edge.
These are essentially the goals for this project.
How I plan to do these on the RC model
1. Modify a CAD model of a cub fuselage to better resemble Scrappy
2. Idk yet
3. This one is the fun one! I plan on putting real solar panels and lithium ion batteries in the wings, turning them into solar-powered power banks. After doing the math, I found that the amount of power the panels will make without battery assistance is enough to power up to four USB devices simultaneously.
4. Kinda just copying Mike's design. 3D printing likely to be involved.

Sounds as though it will be rigged for long flights if you're using 18650s and solar panels. What motor and prop combo you plan to use?

 

[Taildragger]

Sounds as though it will be rigged for long flights if you're using 18650s and solar panels. What motor and prop combo you plan to use?

At some point I may use it as flight power but at the moment the plan is to use them solely for accessory power, such as USBs (phone charging), a UBEC to power the lights and servos, etc.

 

[Beaver5150]

At some point I may use it as flight power but at the moment the plan is to use them solely for accessory power, such as USBs (phone charging), a UBEC to power the lights and servos, etc.

Right. I was using a 4.8v NiMh pack for a minute (4xAA) for onboard power till I found 6A-UBEC modules for near 5$ that run on 2-6S.

 

[OliverW]

You're giving me another reason to fly there this year 😎 I'm going to try and fly up and fly formation with my buddy the way there.

 

[Taildragger]

You're giving me another reason to fly there this year 😎 I'm going to try and fly up and fly formation with my buddy the way there.

if you need to charge your phone when you show up you know where to look!

 

[Tench745]

Or you could wait till Horizon Hobby releases one for $700.
^This is sarcasm^
Build this awesome beast!

 

[Taildragger]

Or you could wait till Horizon Hobby releases one for $700.
^This is sarcasm^
Build this awesome beast!

Horizon won’t have as much functionality too lol

 

[Musdang]

Horizon won’t have as much functionality too lol

$150 electronics, $200 plane (detail), $350 name.

 

[Bo123]

What wingspan you looking at?

 

[Taildragger]

What wingspan you looking at?

About 56-60in is what I’m building, horizon is probably going to do a 2m

 

[Taildragger]

wiring diagram, 36!!! total solar cells each making about 5v 50-60ma, groups of 9 are wired in parallel to make 4 outputs of 5v and about .5amps, each charging one 3200mah 18650 Lithium Ion battery.

@KN4IUU you're into electronics right? lol

 

[FlamingRCAirplanes]

wiring diagram, 36!!! total solar cells each making about 5v 50-60ma, groups of 9 are wired in parallel to make 4 outputs of 5v and about .5amps, each charging one 3200mah 18650 Lithium Ion battery.
View attachment 225190

@KN4IUU you're into electronics right? lol

😍😍 yes I am!! 👍 Are you charging the lithium batteries with a lithium charger circuit?
I would get four of these, make life so much easier
https://www.adafruit.com/product/1904
It charges at 500mah so pretty close to your 450

 

[FlamingRCAirplanes]

Your taking this to FliteFest right?

 

[Taildragger]

😍😍 yes I am!! 👍 Are you charging the lithium batteries with a lithium charger circuit?
I would get four of these, make life so much easier
https://www.adafruit.com/product/1904
It charges at 500mah so pretty close to your 450

yep, trying to find both a BMS for the 18650s, and a voltage regulator since the panels don't always make 5v, they fluctuate from 4-6