I have designed these brackets for my HyperCube printer designed by Tech2C here: http://www.thingiverse.com/thing:1752766 Since I don't like mounting the led strip around the extrusion, I wanted to utilize the spaces between the corner brackets. Because of the presence of XY_Idlers on the back side, I had to make two different types of brackets for front and back of the extrusion corners. Brackets are designed for power led chips aluminum plate heat sinks which is illustrated in 3rd picture. For powering the led chips, I soldered them in series with an appropriate thin wire after soldering the leds to the heatsinks. After printing the brackets, glue the heatsinks to brackets with CA+activator or something similar. For attaching the brackets I have used double sided tapes. Or maybe a hot glue can be used instead.