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Just thought I'd write a post describing my first quad build.

Parts list:

• Hobbywing (or clone?) X-450 glass fiber frame (205 g), x-configuration
• APM 2.5 with U-BLOX GPS
• Electron 6 channel 35 MHz receiver (Hitec Optic 6 transmitter)
• Hobbywing Quattro 4x20A switching ESC (no power distribution necessary!)
• EMAX CF2822 1200 kv motors
• 10x4.7 CW/CCW propellers
• 3DR 433MHz telemetry kit

I have also ordered a camera pan/tilt mount, and consider adding a Gopro HERO2, then connect the video out to a 5.8GHz video transmitter for FPV capability. I'm still waiting for the EMAX motors and the ESC before first flight.

A minor inconvenience was that the 3DR telemetry kit cable does not fit the new mini-JST style radio connector on the APM 2.5 board. I could not find a compatible connector in any local electronics store. However, opening up an old Logitech laser mouse I found the USB cable was attached to the circuit board with the right connector! Problem solved. Unfortunately the optical flow sensor in this mouse was some Logitech undocumented proprietary 20 pin chip, so only the connector was usable for the quad.

I'm unsure if the motors and propellers are a good match for this frame. According to some specs I found, each motor should produce a maximum thrust of around 700 grams with these propellers without exceeding the power of the ESC. I think the minimum recommended total thrust is about 2x the weight of the aircraft - my current setup is about 4x the weight...

The APM 2.5 board is mounted with zip ties on top of some soft non-conducting foam for vibration insulation. I think the zip ties will transfer most of the vibration anyway - the first flight will tell. The U-BLOX GPS is currently mounted on a single nylon standoff. I don't think this will hold during flight (or crash), so I will probably mount it under the CD-R spindle lid which fits nicely over the electronics.

I have ordered some 22 mm hex standoffs so that the space between the top and bottom plate of the frame will have room for the ESC. I added some cut-to-length velcro strips to the bottom plate to mount the battery.

Next update will probably be when the final parts arrive... stay tuned!