I’m using this to organize my 3D .stl files and can’t figure out how to rotate my models on a z-axis in the viewer. I can click and drag to rotate things this way this way 
(rotates around x-axis, top comes towards or away from me vertically), or this way 
(rotate around y-axis, top still comes towards and away from me but horizontally), but not this way 
(rotates around z-axis, top goes in a circle left and right along the x-y plane).
Not sure if this made sense! Especially because once you get rotating, the axes sort of move around with the model and everything gets a little wonky.
But basically, is there a key I need to hold or something in order to change my axis of rotation? Or is it only possible to rotate along 2 axes?
There also seems to be a limit to rotation around the x-axis that excludes some amount of the 360 degrees, so I can’t look completely at the back of my model. Is this on purpose?
This may help! I am trying to make it rotate this way 
