Got a new Vario today, and set forth to calibrate it. An initial test showed it wasn't very close, so I turned the adjustment tool a few turns "finer." Still not close, so I turned some more . No luck. Worse, the adjustment screw at some point seemed to start turning very freely, with no effect whatsoever. I feared I had unscrewed it or something. So I took the top burr out, then the bottom burr, then removed the faceplate, then removed the case, then removed the chute--and I still couldn't see how to access the adjustment screw. So I put it all back together, and noticed I couldn't move the macro lever all the way up without the motor laboring--the grinder was adjusted way too fine. After tearing out some hair, I looked closely at the adjustment tool--and noticed that the tip was more or less round, not hexagonal: I had stripped it. A quick trip to the belt grinder to shorten the tool a couple mm and I had a working adjustment tool. A few turns in the coarse direction and everything was perfect.

Lesson learned: sometimes you strip the screw, and sometimes you strip the tool.

Ah, so I'm not the only one who stripped my adjustment tool, not very strong steel I guess. I just grabbed one of my allen wrenches of higher quality and used that. Great idea with the belt grinder, I'll use my tool sharpening grinder and file it down.

You should adjust the "adjustment" with the macro and micro sliders fully out. This way you won't be mashing the burrs together and breaking the tools. Then you slide the macro up, then slowly, the micro.