Set the W axis to zero, and see if that fixes it. http://help.autodesk.com/view/3DSMAX/2016/ENU/?guid=GUID-C65A1B09-3670-4E7E-BCFC-13E10C831817 You can use the UV/VW/UW dropdown (top right) to see W. Then select all verts. Then use the Absolute Type In (bottom left) to set W to zero.