If you set the empty SKP's Model Info > Units to meters, with say 3dp and no units displayed you can input all of you dimensions as if they are centimeters [or even millimeters provided you are consistent] - thus you'll avoid the issues around the inability to make tiny facets on some meshing operations.
Once you are done... IF you must make it back into the 'real' size then draw a temporary line 1 'unit' long [actually it's 1m long, but from your viewpoint it's 1cm !]; now reset your Model Info > Units as desired; now in the Model run the Tapemeasure tool and click on the two ends of the temporary line and immediately type in 1cm, when prompted say 'Yes' to scale the entire model... everything in the SKP is now the right sizes in cm - and the now very tiny facets can exist, although their creation was not possible without the 'units/scaling' trick earlier...
PS:
You can use the Scale tool as Gaieus suggests BUT then any groups or components will be scaled BUT their original size is unchanged [unless you do further work] - unlike with the Tapemeasure re-scale trick...
