[QUOTE=Jane Quilter;7598305]I have never tried it. What makes it work? the thin edge or is the marker made out of a special material?[/QUOTE. i put the piece of fabric with a 80/20 batt behind it on my sewing table. I placed my ruler where I wanted the line and I used the thin curved edge to draw along the ruler (pressing firmly) pulling it towards myself. I have an arborite sewing table so I didn't have to worry about leaving marks on my table. I would protect the surface of a wood table.