I would suggest heating it quite a bit before bending it. 3/16" is almost 5mm thick. Heating it will make it easier to bend and help reduce stress cracks...
I dont think i will need to bend 3/16' 6061, should be plenty strong :)
Benjamin White
R/c Monster Team Driver
Jq the car, LST, Sportweks turmoil pro
Unconventional Techniques, Superior Results