pic: VersaDrop GrassHopper Drive

[Chak]

Originally Posted by LCJ

The main reasoning behind using the double reduction gearbox was because the height of the wheel using a clamping gearbox was way too high to get enough traction going. The current design has a 1/8" drop and to get it there, I had to use a gearbox with an output shaft that could be mounted anywhere. The reason I used the particular gearbox was because I liked the long output shaft (compared to VersaPlanetaries) and it was also one of the cheaper options from Vex. The reduction options were nice too (for when I inevitably screw up ).

You can insert washers or other spacers at the gusset to lower the entire middle bar down 1/8". That might mess up mechanisms placed on top of the middle bar though, as well as make it more irritating to disassemble and reassemble with washers/spacers rolling around everywhere. I don't think you would ever be required to remove the middle bar, but it's still a disadvantage.