If you have ever see a Y6 multicoppter it will probably have had three arms with a motor on each side, well here is a design which has an arm for each motor but still has the same setup as the traditional Y6 feel.
The way that it is currently designed requires the arms to be connected via rivet, but you could probably modify the design and glue the arms together with super glue. The flight controller i designed this frame for is the KK board but you can probably use any controller with 45mm spacing.
I know this design is inefficient because of the extra weight that the arms give the frame.Technical details (sort of):
6 inch prop
3mm mounting holes (for motor)