Both FlorentF31's design and the original Sigan 180 quad are great design's but found that I had to tweak / scale them to get it into my printers build volume, that along with wanting to use 22XX motors I was needing a more "modular" design.

Update 23 June 2016.

after yet another... test landing (crash) it highlighted that the motor mounts were a little weak without the support of the top casing, I have added 2 new files that now add a power strut around the motor mounts and down the arm, adding strength to the arm and doubling as landing skids.. win win.. have fun flying.
New files:
~V5_Rear_arms.stl
~V5_Front_arms.stl

Sub $100 electronics kit.

~ Complete Kit - I have found a great parts kit that has everything you would need to get this in the air, the only additional item would be a RX receiver.

Training quad.

The Warlark pro 85 is a great learner brush-less quad that can be flown both indoors and outdoors, and its UBER fun!

Parts List..

As complete as I can make it.
~ Aluminium hex spacers, 5.5mm versions so make sure you print the correct case for these, your gonna need 17 of them.
~ M3x6mm allen cap head screws, 50 of these fella's to hold the case all together and mount the motors
~ M3x8mm allen cap head screws 4 of these for the camera assembly.
~ M3 aluminium washer you can use these if you like but they not necessary, if you do use them don't add any to the motor mounts or to the 4 screws closest to the motors on the top of the case, those are sunk for a reason (not to clash with the props)
~ M2 nuts and screws 4 of each to mount the LEDs to the legs', 2 extra screws to mount the servo to the auto tilt gimbal.
~ XT60 connector 1 off
~ Skylight LED boards for the front legs, 2 of any colour you prefer.
~ OSDoge I stacked this on the PDB not the FC
~ Matek PDB
~ SP Racing F3 flight controller.
~ Mini VTX
~ FPV camera, the board cam can be mounted onto the auto tilt gimbal.
~ SG 90 servoused in the auto tilt gimbal
~ Video antenna, these were the RP_SMA versions as that matched my VTX and reciever.
~ Runcam2 optional but great for capturing all the fun..
~ Props, many!!!!
~ 2204 Motors 3, no 2.. ok, ok 4 of them..
~ ESC 4 off of course..
~ Assorted Nylon M3 spacers and nuts, for mounting the FC, PDB and OSD, the nuts can also be used to mount the camera assembly.
~ Battery strap
~ Lipo batterylots.. in fact, get even more.. and a charger
~ Radio reciever the D4r fits really well and has more than enough channels when connected in PPM.
~ Some wire to connect it all up..

I think that was about it... I would suggest checking placement of all items before doing any soldering... don't know how many times I de/re-soldered my FC pins...

Update 03 May 2016.

I have received multiple request's to make provision for a 5.5mm (between flats) spacer. I have added 2 new files for this, so if you plan to use 5.5mm spacers then print these two case files as opposed to the originals:
~ Rear_case_5-5mm spacer option
~ Front_case_5-5mm spacer option

Update 3 April 2016

Took the V4 out for a maiden flight, it is MUCH more rigid and in short I am much happier with the overall design, even decided to do a few crash test's :-) by means of dropping all power from about 10feet up and ditching it into the ground at full speed, surprisingly all arms remain attached, one crash sent the battery flying but otherwise everything was ok and its still flyable, the main weak point was the FPV antenna mounting point, but this was a given really..here is the damage:

And this is what I have added as a more, "learner friendly"option, so you would only need to reprint the FPV VTX mounting section as apposed to entire rear frame, I still need to test the effects of this change on the rigidity, but don't foresee a problem as the current one is broken through and is still very stiff.

The above has been added as V4_Rear_case_option2.stl (print it with supports).

Update 30 March 2016. Moved design to V4

~all V3 files moved to zip filder (still available)
~included V4 sketchup export for any modifications you may require
~changed design to have single arm pieces that integrate with the bottom plate, see photos
~moved case join points as V3 had all joins at the ame point in the arms, this allowed too much flex in the joints.
~removed case from around motors to allow grip on motors when tightening props,
~included dxf file should you want to have top and bottom plates cut from carbon.
~new design has thicker top and bottom plates that add a lot more rigidity and overall weight has been reduced

Update 15 March 2016

~added a remixed of the ZMR tilt gimbal to fit a tower pro SG90 servo cos that's what I had laying around :-p
~changed the camera holder slightly to allow small screws to be used to mount the camera to the holder
~ changed the left and right side supports so no 5mm aluminium spacer is needed the top has a hex insert space for a 3mm nut while the bottom allows a m3x8mm cap head screw to be placed and a nut can then be used to secure the gimbal assembly to top case plate.
~added FPV top plate with cut-out for lens

All suggestions / idea's welcomed