To replace the 7-inch frame that blew up due to my previous setup mistake, I designed this lightweight 7.5-inch frame.

As a classic example of not learning from my mistakes, I still opted to use a 6mm unibody plate for the main frame, despite the price being close to my limit of acceptability. Nonetheless, I decided to use a 3.5mm carbon fiber plate to reinforce the main frame and provide a lengthy space for battery mount.

Finally, by adding 1.5mm aluminum alloy sheet metal parts, I eliminated the need for a carbon fiber top plate. The O3 air unit, being vertically mounted, can be directly fixed to the aluminum alloy sheet metal with heatsinks. Through testing, it does not overheat sitting still when not recording or during hover recording. Additionally, a universal GoPro mount was added to the top of the frame, preserving the option to use a action camera for filming:‘

Due to the limited electronic equipment space within the frame, the prototype only uses an AIO. Using a taller flight stack may require redesigning the GPS and antenna prints.

The motors adopted are 2306 1350kv, which may seem slightly underpowered for a 7-inch frame, but they are absolutely sufficient for long-range flights and help control the overall weight of the drone. Currently, the frame only supports 16x16 motor mount holes, but I can add support for 19x19 holes if needed.

After all modifications, the total weight of the drone without the battery is 490g, and with a longer long-range antenna and the magnetic quick-release mount for the Action2 camera, it reaches 525g.

The prototype uses a 6s 5000mah battery composed of Mavic battery cells, with a hovering current of 6.8A and a normal flight time of around 25 minutes (landing battery voltage at 3.7v).

Lastly, here is the design video:
https://www.bilibili.com/video/BV19aydYeEhn/?vd_source=8dd0184dc78eb3c62a00e47dd5c2792d

Frame OpenSource Here：
https://www.thingiverse.com/thing:6809556