The last stump grinder i used was a "one" person walk behind. It had two wheels that were powered and star like shaped grinder at the end. The grinding wheel spun so the top of it went away, the bottom toward the operator. It was very heavy and hauled in on a trailer.
This is how i used it, jump up into the air land on to the handle bar arrangement, and in a somewhat gymnastic pummel horse move, swing your legs back, to put weight on unit, to bring the front end of the grinder off the ground. Engage the drive to get where you needed to be, engage the grinding wheel and muscle the unit from side to side. If the grinding wheel dug in too much, the grinder front would jump up and you did not want to be too close to the handle bars, as it would drive you into the ground.
I found a very specific, narrow method that the grinder was most effective at grinding the stumps. If i could get the grinder to just barely engage the stump on the top edge, it would slice/split the grain down, then cut off at the bottom. I think that worked better, because the cutting teeth didn't have to start the cut cross grain, but rather, split the wood then pull out across the grain. So what im getting at, if you have reversed the wheel so that it throws the chips away, it my have a harder time chipping. If the wheel is turning so that can engage the stump on the top, the downward, it will take less power to chip.
