If you're looking to take a subpar frame like the Mark 4 and make it fly even worse, this project is for you.

Motors and Frame
With an inverted offset pusher on the front, it can run a 7-inch prop, providing moderate efficiency and about 8 minutes of flight time on a 6S 1300mAh battery. The battery mount is designed to run two 4S 1500mAh batteries in parallel for extended flight time, but in this configuration, it flies like a brick. Use motors around 1600KV for moderate performance. The rear tail boom for the Y4 setup screws together with M3 hardware and metal standoff spacers, sandwiching the original Mark 4 arm in between. Ensure everything is tight, using washers and cranking the screws down if they are not snug (Loctite recommended). WARNING: This design has a tendency to get stuck at full throttle when yawing aggressively. Do not fly indoors or near people.

Landing Gear
The landing gear screws together with M3 hardware but needs minimal resistance in the joints while still being rigid enough to prevent servo binding. Use a 9g 180-degree metal gear servo, but be careful as it can fry the 5V regulator on the flight controller. Loose elastics work to retract the rear arms, and a string connects the rear landing gear to the forward gear. The base unit screws into the bottom of the Mark 4 frame.

I advise against building this on good parts, as its sketchiness adds to the thrill of flying longer missions, and it would be a real shame to lose good parts on a frame this bad. Increasing the filtering and lowering the master can help with flight performance a bit. Additionally, lowering the yaw rate and flying as smoothly as possible can improve flight performance.

Possible parts:
6s motors
4s motors
stack
vtx
camera
Reciver
Antenna
Servo

If you do for some ungodly reason deicide to build one of these I wish you luck

Creality

Ender 3 Pro

No

Yes

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