This quadcopter is about 22mm longer and 2mm taller than the popular T4 Quadcopter Mini 250. It supports up to 8" props and a 2200mah 3S battery.

Check out the whole "T" copter family:

• TX8 Octocopter
• T6 Hexacopter
• T4 Quadcopter (10" props)
• T4 Quadcopter Mini 315 (7-8" props)
• T4 Quadcopter Mini 250 (5" props)
• Tubular Crossfire 2 quadcopter
  I've added a post on the forums over at DIY Drones for discussing and improving these designs.

  Videos

• Build video playlist
• Build video 1: Body assembly
• Build video 2: Install motors
• Build video 3: ESCs and power
• Build video 4: Flight control
• Frame strength testing
• First flight

  Features:

• completely 3D printable (without support)
• fully assembled frame weight less than 130 grams!
• strong, simple assembly with no bolts to save weight! Everything is secured using 2.5mm zip ties.
• includes two arm options - 28mm, and 30mm motor cup (inside diameter). The 30mm cup has slots for 3mm motor bolts (the other is 2mm).
• strong braced tube section arms with plenty of room to conceal motor wiring
• designed for a 3S battery (up to 2200) located right in the centre of rotation/thrust (110 x 38 x 24mm capacity).
• plenty of space to mount ESCs - concealed but still well ventilated for cooling.
• top plate has space for a variety of flight controllers and a Mobius style camera. It also features 3mm mounting holes so stand-offs could be used to add an additional deck of components. Alternatively two hex holes are available to add 3D printed posts and rear upper deck.
• RF "invisible" frame - as opposed to carbon fiber or aluminium
• Sketchup file included so you can make changes to suit yourself

  Revision History

  2 September 2014
  Legs for your T4 Mini are now available.
  31 August 2014
  Version 1.3
  Added a bridge to T4Mini315VibrationFloatingPlate.stl to make it less flexible. No other files were changed.
  15 August 2014
  Version 1.2
  New vibration isolating top plate option. This option is compatible with previous body and all other components. It replaces the top plate with one that has mounting points for 65 gram vibration damping balls that then connect to a new floating plate to hold your flight controller and camera.
  New files:

• T4Mini315VibrationTopPlate.stl
• T4Mini315VibrationFloatingPlate.stl
  30 July 2014 - Version 1.01
• there seem to be a lot more 8" prop options so I've added two arms to suit 8" props (28mm cup and 30mm cup).
• extended the 7" arms by 5mm to give a bit more clearance from the body.
• modified the body to raise the arm sockets so there is a bit for material in the bottom of the socket - stronger to support longer arms.