For removing endmills from the collet, always remember to have a thick wad of cloth underneath just in case it slips out of your fingers. Hitting the bed or the floor will likely chip it. It is best to touch down with a carbide end mill when it is running, not stationary. If you absolutely have to have the spindle stationary, then put something of a known thickness between the job and the cutter, a sheet of aluminium will cushion the cutter from chipping on steel.