You could finish off the cut edges like the old style sewing cabinents. The hole is cut larger than the size of the machine. Out of the piece of table that you cut out, cut strips out slightly smaller than needed to fill in the gap between the table and the machine, hinge these pieces in. If these come up snug to your machine and you get the right type of hinges, you could get a fairly flat and flush surface from your machine to the table. You could also put countertopping on the surface of the table to make it slicker, too.