This has been the season of creative engineering for me but I am out of ideas for this particular problem. We have 5 rather large heavy doorways that the designer would like to move easily around the stage by actors. My first thought was that we would caster the units with low profile casters but the designer does not want the base to be more than 1" high. So, we inset casters inside the legs of the doorways and used furniture pads on around the perimeter of the base. They move great but the problem is that the plastic on the furniture sliders are scratching the mess out of the floor. Does anyone have any ideas on what kind of sliders we could use on these doors that won't scratch the floor but still provide ease of movement for these "dancing doors"?