Chances are Alistair you will damage your IBC, KO and Aussie robot uses 4 x 12v XU1 drills on 24v and gets its IBC warm, I would hate to see what 6 would do.

The robot Singularity has 6 x 12v drills @ 24v, but it runs an RD80 Robot Solutions speed controller with the current limiting cranked up.