Cube FPV

Gep RC Smart 35

AIO FC Stack Build

With this build, we look at fitting out the Gep RC Smart 35 with an AIO flight controller, and in particular taking advantage of the central and rear stack mounting positions combined. Mounting offset layers in the stack in this way allows us to include a Fettec spike absorber, naked Vista unit and Receiver all in the stack.

Stack Design Considerations

Mounting Positions

A standard build with this airframe would either use the central stack mounting position only, or use the front and rear mounting positions for a dual stack (as shown in my other build). However, in this build, the middle stack and rear stack have been used (combined) to make an offset stack. This is done by using the rear poles of the mid-stack as the front poles of the joined rear stack. 


Offsetting the layers of the stack alternately in this way gives more room for components in the stack. The only consideration is ensuring there is enough clearance in the pole position where the two layers both mount. An example of this can be seen with the Fettec spike absorber, which is moved further back on it’s mounting plate to allow clearance with the board of the Vista unit.

Flight Controller Mounting

The flight controller is mounted upside down to make the best use of space in the stack. With flight controllers, it is best to have at least 2 mm clear gap between any circuit board components on the bottom and the frame. This flight controller have a JST Connector for the Vista unit as well as a USB 2 connector on the top. I have turned the flight controller over, so these components can take up the space between the FC and the frame, giving more space on top in the stack.

Stack Build Process

The images below show the layup of the stack in a step-by-step guide. Refer to the video below for a step by step description of the spacers used between each layer in the stack.

YouTube Overview Video

This video takes you through the build process and explains the layering of the stack. 

Play Video

Frame Layout Images

Frame Resonance Examples

Screenshots from a blackbox log. This is a 1 minute 14 second flight doing aggressive manoeuvres around all axes and throttle ramp up punchouts. The resonances in this frame are not excessive at all. A small amount of frame resonance is visible at one position each on the roll and pitch axis. Both of these points are well taken care of with filtering.  

Pitch Axis

Roll Axis

Yaw Axis

Parts List

Related Content

Smart 35 Frame Review