A few 3D printers have an alternative in their menu for loading and unloading filament. Just before you commence loading/unloading, then be certain that the extruder isn't previously loaded with all the filament. When there is filament from the extrusion mind, remove it first. If your 3D printer has an choice for removing the filament, put it to use and then watch it until it unloads out of your extrusion head. Visit this site: http://zilla3d.com/ZillaGrip-Cold-3D-Printing-Coating-_c_20.html