Adding an SD card holder
(De)select All objects (A) and press Shift + H. Remember that Shift + H hides all but the selected object; however, as no objects are selected, all objects will be hidden to clear the way for what is to come. Add (Shift + A) a cube to the scene.
It is interesting to note that the default cube created by blender is not a unit, that is to say, its sides are not all 1 mm. They are in fact 2 mm each. This makes the default cube less desirable for precise scaling. Fortunately, it is an easy thing to make this cube a unit cube; however, first its dimensions can be used to move it on to the XY plane easily. Only this time a trick will be employed to control how the cube scales in the future. Instead of moving the whole cube up, the individual points will be moved up in the Edit Mode so that the object's origin is left where it is.
Note
Object origin was a problem in the last project causing the object's axes to be skewed in relation to the world orientation. In that project...