I have been in the Roller Door/ Industrial Roller Shutter biz for more than 20 years and always used silicone spray lube as the mineral oil in WD40 , rp7 and the like melts the rubber that is inside the nylafelt (edge strapping) on some brands of doors it also attracts dust. Until a few years ago when WD40 brought out 3in1 Garage Door Lube and that is what I use now.....Michael