I have never been able to shave with a safety razor without slicing my face, so I use a rotary electric razor instead. In weightlessness they work just as well, and the whiskers are captured inside the shaving head. But how does one clean out the whiskers in weightlessness?
In March 2001, Jim Voss, Expedition 2 flight engineer, shaves with an electric razor.
On Earth, you simply open the head and shake them out. Doing that up here would be a disaster.
So once a week, when vacuuming the accumulation of lint, dust, and detritus against the air inlet filters, I vacuum my razor. I hold the vacuum cleaner hose between my legs, and use both hands to carefully open the shaving head in front of the suction. A cloud of whiskers jumps out, appearing like a miniature asteroid field, then quickly disappears into a black hole, with no chance of escape.
Ten years later, In July 2011, Ron Garan, Expedition 28 flight engineer, trims Mike Fossum's hair with a vacuum attached to the clippers.