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Intro

The Breeze Model X is the latest addition to the "Breeze" series of RC planes.

• Customizable upgrades
• Lightweight yet strong
• Modular design
• SUB250 compliant
• Few parts to assemble
• Completely FREE to download

License:

Breeze Model X is available for free download and non-commercial use only when downloaded exclusively from MakerWorld.com. Please contact me for authorization if you wish to use it beyond the Standard Digital File License.

As I will continuously enhance this model base on your feedback, please revisit here for updates.

The Breeze Model X is a SUB250 modular flying wing, designed to weigh less than 250g, allowing for easy compliance with aviation regulations in many countries. This design means you can enjoy flying in most regions without the need for a remote identification tag. However, it's important to verify your local laws and ensure you fly in safe, unpopulated areas since it can go very fast.

It flys notable responsiveness, offering a firm yet reactive feel, which suits aerobatic maneuvers. It can rolls and loops easily.

Additionally, it features an efficient wingfoil, achieving a tested glide ratio close to 12 (which means it descends 1 meter for every 12 meters it glides).

Flying characteristics:

In my fly test.

Wing Span: 560mm (incl. winglets)

RTF weight: ~250g

Battery: 3S 1300mAh

Motor: 1406 3300kv

Prop: Gemfan 3inch 3052 (high pitch blades for speed)

Glide Ratio: ~12:1 @ 12m/s

Stall speed: 7.5m/s or 27km/h

Cruise Speed: 15m/s or 54km/h

Top speed: 30m/s or 108km/h

Cruise throttle: 50%

Cruise Time: 45min

Thurst to weight ratio: 0.9

Print Time: ~10 Hours vase mode PLA-Aero or LW-PLA

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Note : Per user feedbacks, if you want to print with non-foaming materials such as PETG, you will need a 3S 18650 pack to get the COG right (normal lipo is too thick for the fuselage and the canopy wont fit). Prepare for heavier wing-load (stall speed will be increased massively)

This extended nose parts allows you to fit smaller battery 

while still making COG right. Thanks to the author

https://makerworld.com/en/models/465958#profileId-374847

BOM besides printable parts and Fly Controller

• 5 x 300mm Carbon Tube x 1
• EMAX 9g servo x 2
• Push rod 1mm to 1.2mm diameter, at least 11cm length x 2
• M3 5mm Nylon screw x 3 (Optional)
• M3 thread insert x 3 (Optional)

Recommended Filaments

Bambu Lab ASA-Aero: https://us.store.bambulab.com/products/asa-aero

Bambu Lab PLA-Aero: https://us.store.bambulab.com/products/pla-aero

Tuning before mainden

• Mixer setting:

Pitch 60% Roll 30% – this is critical, because this plane has large control surface, and roll is too sensitive.

• INAV PID setting (under testing):

I am still finding a good PID, will update you here. Mean while, please reduce roll PIDFF rate which the default values are really unstable.

Old setting 2024/04/13:

• pitch rate: 150 deg/sec
• roll rate: 310 deg/sec
• Lower all Roll PID by half. Set roll FF to 60.
• Lower all Pitch PID by 25%. Set pitch FF to 80.
• (Important) Enable advance PID and lower “level strength” to 8.

Current suggestion 2024/05/03:

# Mixer: servo mixer
smix reset

smix 0 1 0 -30 0 -1
smix 1 1 1 -60 0 -1
smix 2 2 0 -30 0 -1
smix 3 2 1 60 0 -1

# PID and rate setting
set fw_p_pitch = 10
set fw_i_pitch = 10
set fw_d_pitch = 5
set fw_ff_pitch = 70
set fw_p_roll = 8
set fw_i_roll = 5
set fw_d_roll = 5
set fw_ff_roll = 51
set fw_p_level = 10
set roll_rate = 30
set pitch_rate = 17

# save configuration
save
 

Please give suggestion if you have better turning.

Once it is stable, I will export the setting cmd, and you could apply it in one go.

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Design Principle

Alternative source (Chinese via bilibili):

3D printed RC planes often seem stiff and easy to break, getting damaged from small crashes that foam planes usually handle well. To fix this in my design, I focused on two main ideas:

• Lightweight and Strong – be SUB250 and resistance to small crash.
• Modular design – easy to swap broken modules and customized options.

Also, foaming filaments (like PLA-Aero, ASA-Aero, LW-PLA, etc.) usually have issues with strings in normal printing. But, a special printing way called spiral vase mode can solve this by drawing the shape's outline all at once without stopping. This needs a special design trick to make sure every layer can be drawn in one go, with each layer sitting right on top of the last one. This lets Bambu Studio make a continuous printing line, avoiding any stops and moves.

The design was tricky, but don’t worry about it. I did the hard work, and you can just print with the profiles I shared.

NOTE: DO NOT rearrange the foaming parts, they need to be print one each plate with set spiral-vase mode.

This flying wing has only 6 parts (3 big and 3 small), which have to be printed one by one in vase mode with foaming filaments. The other parts can be printed all together on one plate with regular filament.

There are way fewer foaming parts than other RC planes you might see for sale. And printing this whole plane takes only about 10 hours, which is a lot less time than others that take 50+ hours.

Lightweight and strong

You might see some red parts in the pictures. Most of these aren't made from foaming material; they're actually for making the plane stronger. While the foaming parts cover a lot of the area and add to the weight, these regular material parts make it much tougher in important spots like where the motor is, the front edge of the wing, the nose, the bottom, and parts that let you swap things easily.

These red parts help the wing handle normal landings and minor crashes without getting damaged.

The weight ratio between foaming material and regular material is about 4:1.

Modular and easy to assembly

Even with its lightweight and strong design, the plane can still crash badly. When a crash happens, a typical 3D-printed plane has little chance to survive. But with this design, wings or broken parts can be easily swapped out thanks to the quick-swap connectors, a feature from the start.

One of my goals was to make repairs possible right at the flying site. The solution? Make everything changeable.

Yes, even wings of this small size have a quick-release system that allows for disassembly in no time, all without a single screw.

I always have a set of wings and a body ready to replace any broken parts. During my flight controller tuning and plane optimization, I used up one plane on average each time. However, this wing design does a great job protecting the electronics; I've never lost a servo or any electronic part.

The assembly of each module is as simple and straightforward as possible. I really enjoy the building process, and I think you will too.

Assembling a complete plane takes less than 30 minutes once you're familiar with it. And you shouldn't need to tune your new plane much, because 3D-printed RC planes always have accurate dimensions.

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Assembly Guide

Video Assembly Guide

video: To be uploaded

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Customized your planes

I've designed many options to enhance the capabilities of these small wings. Some are aimed at improving flying characteristics, while others boost functionality, like FPV (First-Person View) capabilities. Please see below for the different options available.

Winglet options

The Lite version, as the default option, is small and lighter, designed to meet the SUB250g regulations. This makes it perfect for those who want a compact and efficient flyer. On the other hand, the Large version offers more lift and better yaw stability, making it suitable for those who prefer a plane that can handle more varied flying conditions. More info please checkout this amazing explain video:

FPV cap options

The default is the flat top, you may mount your DIY camera on it. Besides, I've also created 2 options to make your FPV setup easier:

• A 19-20mm top mount with a camera canopy. Print the camera mount with regular filament and glue it on top.
• A mounting frame for a special O3 camera module taken from BetaFPV Pavo 20 O3 module, can be purchased from their website. It's the most affordable and lightest O3 frame I've found, and it even includes dampers for stabilization. This setup works great, and I highly recommend it.

Motor mount options

The default motor mount fits 1304 to 150x motors, which are plenty for this small plane. You can try other motors, but remember, larger motors are heavier. You'll likely need to adjust the canopy to fit larger batteries and keep the center of gravity (COG) correct.

By the way, the EDF didn't hit the advertised 200g thrust, only reaching 140g. However, it's still flyable and looks very cool.

Sled options

The spring-loaded sled is for hard surfaces like rocky roads and off-road terrain. Hard surfaces can easily damage foaming parts, so a spring can effectively absorb the vibration and impact, thus protecting the body.

For soft surfaces, like grass fields, a hard sled is sufficient.

Nose options

If you prefer not to mount the camera on top, you can use the camera nose instead of the standard one. It also accommodates a 20mm camera frame for an FPV camera. However, placing the camera at the very front of the wing is quite risky.

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More Vids

BetaFPV Pavo 20 O3 modual on Breeze MX test video.

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Tips

• Rotate your flight controller by 90degree to save some space for battery.
• Use fast servos, this is a agile wing.
• Get the COG right,
• Don't tilt the ailerons up like you might on other wings. This wingfoil already includes that effect, and the twist-wing design also contributes to pitch stabilization.