Sew Steady is a brand of plexiglas surface extension table to use when your machine sits on the cabinet or table. Some of the adaptations can be used to fill in a dropped surface, and not all of them are plexiglas. My Sew Steady table is over 25 years old and very basic, not enough leg supports. I've seen many photos of home made tables and inserts, some on here. Patsy Thompson has a series of videos on free motion quilting, and in "Fast and Free" volume 2, her husband shows how to build your own extension table.